Orthopedic Board Review MCQs: Lower Extremity Trauma

About This Board Review Set

This is Part 155 of the comprehensive OITE and AAOS Orthopedic Surgery Board Review series authored by Dr. Mohammed Hutaif, Consultant Orthopedic & Spine Surgeon.

This set has been strictly audited and contains 100 100% verified, high-yield multiple-choice questions (MCQs) modelled on the exact format of the Orthopaedic In-Training Examination (OITE) and the American Academy of Orthopaedic Surgeons (AAOS) board examinations.

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Topics Covered in Part 155

This module focuses heavily on: Ankle, Arthroplasty, Foot, Fracture, Knee.

Sample Questions from This Set

Sample Question 1: A 30-year-old woman injured her ankle playing soccer 3 months ago. She now reports popping and pain over the lateral side of her ankle. An MRI scan is shown in Figure 33. What structure needs to be repaired to alleviate the popping?...

Sample Question 2: You are interested in learning a new technique for minimally invasive total knee arthroplasty. The Keyhole Genuflex system seems appealing to you because the instrumentation comes with wireless controls. Which of the following represents an...

Sample Question 3: A 7-year-old girl reports foot pain and has difficulty ambulating. History reveals that she fell off a scooter 1 week ago, and there is possible exposure to a tick bite. A radiograph is shown in Figure 29. What is the best course of action?...

Sample Question 4: A 40-year-old man is thrown off his motorcycle and sustains an open Type IIIA fracture shown in Figure A. He is taken to the operating room for debridement and reamed intramedullary nailing with a 10mm diameter nail. He returns at 10 months...

Sample Question 5: A 16-year-old boy sustains a twisting injury to the left knee while wrestling. MRI scans are shown in Figures 22a through 22c. What is the most likely diagnosis?...

Why Active MCQ Practice Works

Evidence consistently demonstrates that active recall through spaced MCQ practice yields substantially greater long-term retention than passive reading alone (Roediger & Karpicke, 2006). All questions in this specific module have been algorithmically verified for clinical integrity and complete explanations.

Comprehensive 100-Question Exam

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Question 1

A 30-year-old woman injured her ankle playing soccer 3 months ago. She now reports popping and pain over the lateral side of her ankle. An MRI scan is shown in Figure 33. What structure needs to be repaired to alleviate the popping?

Explanation

DISCUSSION: The symptoms and MRI scan indicate dislocated peroneal tendons. In this patient, the structure that needs to be repaired is the superior peroneal retinaculum. If the popping was coming from a torn peroneal tendon, repair would involve the peroneal longus or brevis tendon, but this is not shown in the MRI scan. The anterior talofibular ligament or the calcaneofibular ligament would need to be repaired if the patient had ankle instability due to an ankle sprain.
REFERENCES: Jones DC: Tendon disorders of the foot and ankle. J Am Acad Orthop Surg 1993;1:87-94.
Timins ME: MR imaging of the foot and ankle. Foot Ankle Clin 2000;5:83-101.

Question 2

You are interested in learning a new technique for minimally invasive total knee arthroplasty. The Keyhole Genuflex system seems appealing to you because the instrumentation comes with wireless controls. Which of the following represents an acceptable arrangement?

Explanation

DISCUSSION: Both the AAOS and AdvaMed, the medical device manufacturer's trade organization, have written guidelines that address potential conflicts of interest regarding interactions between physicians and manufacturer's representatives when it comes to patients' best interest. The AAOS feels that the orthopaedic profession exists for the primary purpose of caring for the patient and that the physician-patient relationship is the central focus of all ethical concerns. When an orthopaedic surgeon receives anything of significant value from industry, a potential conflict of interest exists. The AAOS believes that it is acceptable for industry to provide financial and other support to orthopaedic surgeons if such support has significant educational value and has the purpose of improving patient care. All dealings between orthopaedic surgeons and industry should benefit the patient and be able to withstand public scrutiny. A gift of any kind from industry should in no way influence the orthopaedic surgeon in determining the most appropriate treatment for his or her patient. Orthopaedic surgeons should not accept gifts or other financial support with conditions attached. Subsidies by industry to underwrite the costs of educational events where CME credits are provided can contribute to the improvement of patient care and are acceptable. A corporate subsidy received by the conference's sponsor is acceptable; however, direct industry reimbursement for an orthopaedic surgeon to attend a CME educational event is not appropriate. Special circumstances may arise in which orthopaedic surgeons may be required to learn new surgical techniques demonstrated by an expert or to review new implants or other devices on-site. In these circumstances, reimbursement for expenses may be appropriate.
REFERENCES: AAOS Standard of Professionalism -Orthopaedist -Industry Conflict of Interest (Adopted 4/18/07), Mandatory Standard numbers 6, 9, 12-15. http://www3.aaos.org/member/profcomp/SOPConflictsIndustry.pdf
The Orthopaedic Surgeon’s Relationship with Industry, in Guide to the Ethical Practice of Orthopaedic Surgery, ed 7. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2007. http://www.aaos.org/about/papers/ethics/1204eth.asp
AdvaMed Code of Ethics on Interactions with Health Care Professionals 2005. http://www.advamed.org/MemberPortal/searchresults.htm?query=Advamed%20Code%20of%20Ethics%20on%20Interactions%20with%20Health%20Care%20Professionals%202005

Question 3

A 7-year-old girl reports foot pain and has difficulty ambulating. History reveals that she fell off a scooter 1 week ago, and there is possible exposure to a tick bite. A radiograph is shown in Figure 29. What is the best course of action?

Explanation

DISCUSSION: The child has Kohler’s disease. This is a self-limiting osteochondritis of the navicular. It is treated symptomatically with initial cast immobilization for 6 to 12 weeks, followed possibly by orthotic management. Findings shown in the radiograph usually will normalize within 1 year, and there are no long-term sequelae.
REFERENCES: Borges JL, Guille JT, Bowen JR: Kohler’s bone disease of the tarsal navicular. J Pediatr Orthop 1995;15:596-598.
Mizel MS, Miller RA, Scioli MW (eds): Orthopaedic Knowledge Update: Foot and Ankle 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1998, pp 65-78.

Question 4

A 40-year-old man is thrown off his motorcycle and sustains an open Type IIIA fracture shown in Figure A. He is taken to the operating room for debridement and reamed intramedullary nailing with a 10mm diameter nail. He returns at 10 months with persistent pain at the fracture site with ambulation. Examination reveals healed wounds with no erythema, warmth or tenderness. Erythrocyte sedimentation rate and C-reactive protein levels are within normal limits. Radiographs taken at that time are shown in Figure B. What is the next best treatment step?

Explanation

This man had a mid-diaphyseal tibial fracture that has gone into nonunion. Reamed exchange nailing is indicated.
Tibial delayed union can be defined as lack of union from 20-26 weeks post-injury, while nonunion is defined as lack of healing at >9mths post-injury, or absence of progressive signs of healing on radiographs for 3 consecutive months. Persistent pain is a symptom of nonunion. ESR and CRP are performed to rule out infection.
Bhandari et al. performed a blinded, multicenter trial on 622 reamed tibial nails and 604 unreamed tibial nails. In closed fractures, patients in the unreamed nail group were at greater risk of primary events than the reamed nail group. There was no difference in groups for open fractures. Primary events were defined as bone-grafting, implant exchange/removal, dynamization, and debridement.
Hak reviewed aseptic tibial nonunion. They discuss exchanged reamed nailing for diaphyseal nonunion, adjunctive plate fixation for metaphyseal nonunion, and nail removal and plating for metadiaphyseal nonunion, external fixation for infected nonunion and distraction osteogenesis of defects.
Figure A shows a mid-diaphyseal tibial fracture Figure B shows nonunion following
IM nailing of the fracture. Illustration A shows union following exchange nailing with a larger 12mm diameter nail.
Incorrect Answers:

Question 5

A 16-year-old boy sustains a twisting injury to the left knee while wrestling. MRI scans are shown in Figures 22a through 22c. What is the most likely diagnosis?

Explanation

DISCUSSION: The MRI scans show a displaced bucket-handle medial meniscus tear that can be visualized on coronal, sagittal, and axial views. The sagittal view shows the typical “double posterior cruciate ligament sign,” in which the low-signal bucket-handle fragment parallels the normal low-signal posterior cruciate ligament. The coronal and axial images both show the displaced medial meniscus in the notch.
REFERENCES: Sanders TG, Miller MD: A systematic approach to magnetic resonance imaging interpretation of sports medicine injuries of the knee. Am J Sports Med 2005;33:131-148.
Miller TT: Magnetic resonance imaging of the knee, in Insall JN, Scott WN (eds): Surgery of the Knee, ed 4. Philadelphia, PA, Churchill Livingstone, 2006, vol 1, pp 201-224.

Question 6

In surgically treating hand and finger infections in patients with diabetes mellitus, what factor is associated with higher amputation rates?

Explanation

DISCUSSION: Patients with diabetes mellitus are prone to infection, and surgical treatment of their infections frequently requires multiple procedures. The triad of poor wound healing, chronic neuropathy, and vascular disease contributes to the increased infection rate. Studies have demonstrated increased amputation rates in patients with diabetes mellitus who have renal failure or deep polymicrobial or gram-negative infections.
REFERENCES: Gonzalez MH, Bochar S, Novotny J, et al: Upper extremity infections in patients with diabetes mellitus. J Hand Surg Am 1999;24:682-686.
Trumble TE (ed): Hand Surgery Update 3: Hand, Elbow, & Shoulder. Rosemont, IL, American Society for Surgery of the Hand, 2003, pp 433-457.
Kour AK, Looi KP, Phone MH, et al: Hand infections in patients with diabetes. Clin Orthop Relat Res 1996;331:238-244.

Question 7

9 degress Celsius, serum WBC is 14,000, and his C-reactive protein is elevated. He reports that he uses IV heroin. A coronal 3D CT scan of the left clavicle is shown in Figure B. Joint aspiration shows many grams stain positive organisms. Which of the following organisms is the most likely pathogen?

Explanation

Tibial eminence fracture
Sagittal plane fracture of the medial femoral condyle
Schatzker I tibia plateau fracture
Coronal plane fracture of the lateral femoral condyle
Axial plane fracture through the medial femoral condyle Correct answer: 4
The "Hoffa fracture" is a coronal plane fracture of the femoral condyle that is often missed on plain radiographs of supracondylar and intercondylar femur fractures. It involves the lateral condyle more frequently than the medial.
Identification is important as it may impact operative planning and likely require screw fixation in the anteroposterior plane.
Nork et al. reviewed 202 supracondylar-intercondylar distal femoral fractures and found a 38% prevalence of associated coronal plane fractures. The authors recommend CT scan imaging of all supracondylar and intercondylar fractures.
Ostermann et al reported on 24 unicondylar fractures of the distal femur treated with open reduction internal fixation with a screw construct. Twenty-
three patients acheived satisfactory results at 5 year follow-up. Illustrations A and B are another example of a supracondylar femur fracture with an associated Hoffa fracture identified on CT scan.

A 35-year-old woman presents with an elbow injury which includes a coronoid fracture involving more than 50%, a comminuted
radial head fracture, and an elbow dislocation. What is the most appropriate treatment?
closed reduction and early range of motion
radial head resection and lateral collateral ligament reconstruction
radial head resection and coronoid open reduction internal fixation
radial head arthroplasty and coronoid open reduction internal fixation
radial head arthroplasty, coronoid open reduction internal fixation, and lateral collateral ligament repair
A terrible triad of the elbow includes dislocation of the elbow with associated fractures of the radial head and the coronoid process. Ring et al. stressed that these injuries are prone to complications and advised against resection of the radial head due to instability, and instead recommended a radial head replacement if too comminuted for ORIF. Coronoid fractures compromise elbow stability as well and require open reduction and internal fixation as with the lateral collateral ligament. McKee et al. showed stable elbows in 34/36 with mean Mayo elbow score of 88 when the standard protocol of coronoid ORIF, radial head repair/replacement, and LCL repair were employed.
The talocrural angle of an ankle mortise x-ray is formed between a line perpendicular to the tibial plafond and a line drawn:
perpendicular to the medial clear space
parallel to the talar body
between the tips of the malleoli
perpendicular to the shaft of the fibular
parallel to the subtalar joint Correct answer: 3
The talocrural angle is formed by the intersection of a line perpendicular to the plafond with a line drawn between the malleoli (average = 83+/-4deg). When the lateral malleolus is shortened secondary to fracture, this can lead to increased talocrural angle. This malunion leads to lateral tilt of the talus.
Phillips et al looked at 138 patients with a closed grade-4 supination-external rotation or pronation-external rotation ankle fracture. Although the conclusions were limited due to poor follow up, they found the difference in the talocrural angle between the injured and normal sides was a statistically significant radiographic indicator of a good prognosis.
Pettrone et al looked at a series of 146 displaced ankle fractures, and the effect of open or closed treatment, and internal fixation of one or both malleoli. They found open reduction proved superior to closed reduction, and in bimalleolar fractures open reduction of both malleoli was better than fixing only the medial side.
Illustrations A and B are demonstrations of the talocrural angle.

A 33-year-old male sustains the injury shown in Figure A. He is initially treated with a spanning external fixator followed by definitive open reduction internal fixation of the tibia and fibula. His wounds healed without infection or other complications. Two years following surgery, which of the following parameters will most likely predict a poor clinical outcome and inability to return to work?

Joint line restoration
Degree of fracture displacement
Time before definitive ORIF
Open fracture
Lower level of education Correct answer: 5
Lower level of education is the parameter that correlated most closely with a poor clinical outcome and inability to return to work.
To determine what fracture- and patient-specific variables affect outcome, Williams et al evaluated 29 patients with 32 tibial plafond fractures at a minimum of 2 years from the time of injury. Outcome was assessed by four independent measures: a radiographic arthrosis score, a subjective ankle score, the Short Form-36 (SF-36), and the patient’s ability to return to work. The four outcome measures did not correlate with each other. Radiographic arthrosis was predicted best by severity of injury and accuracy of reduction. However, these variables did not show any significant relationship to the clinical ankle score, the SF-36, or return to work. These outcome measures were more influenced by patient-specific socioeconomic factors. Higher ankle
scores were seen in patients with college degrees and lower scores were seen in patients with a work-related injury. The ability to return to work was affected by the patient’s level of education.
Pollak et al performed a retrospective cohort analysis of pilon fractures. Patient, injury, and treatment characteristics were recorded. The primary outcomes that were measured included general health, walking ability, limitation of range of motion, pain, and stair-climbing ability. A secondary outcome measure was employment status. Multivariate analyses revealed that presence of two or more comorbidities, being married, having an annual personal income of less than $25,000, not having attained a high-school diploma, and having been treated with external fixation with or without limited internal fixation were significantly related to poorer results as reflected by at least two of the five primary outcome measures.
What is the most appropriate treatment for a 17-year-old boy who sustained a gunshot wound to his forearm from a handgun with a muzzle-velocity of 1000 feet/second if he is neurovascularly intact and radiographs reveal no fracture?
Irrigation and local wound care in the emergency department
Emergent irrigation and debridement in the operating room with vacuum-assisted wound closure
Emergent irrigation and debridement in the operating room with 7 days of intravenous antibiotics
Wound closure in the emergency department with follow-up wound check in 1 week
Exploration and removal of all bullet fragments in the emergency department and 10 day course of oral antibiotics
The question refers to appropriate management of a gunshot wound to the forearm. The first question that must be answered when evaluating gunshot injuries is whether the gunshot is low velocity or high velocity. Low-velocity wounds are less severe, are more common in the civilian population, and are typically attributed to bullets with muzzle velocities below 1,000 to 2,000 feet per second. Tissue damage is usually more substantial with higher-velocity (greater than 2,000 to 3,000 fps) military and hunting weapons. In this question, a muzzle velocity of 1,000 ft/sec is provided. Low velocity injuries with stable, non-operative fractures can be treated with local wound care.
The two referenced articles offer guidance for treating low-velocity gunshot injuries with stable, non-operative fracture patterns. The first article by Geissler et al is a retrospective study comparing 25 patients that prospectively received local irrigation and debridement, tetanus prophylaxis and a long acting cephalosporin intramuscularly to a random retrospective sample of 25 patients with similar ballistic-induced fractures and wounds managed by local debridement and 48h of intravenous antibiotics. One infection occurred in each group, requiring further therapy. It was concluded that patients with low-velocity gunshot induced fractures can be managed without the use of short-term intravenous antibiotics with no increased risk of infection.
In the second study, Dickey et al evaluated the efficacy of an outpatient management protocol for patients with a gunshot-induced fracture with a stable, non-operative configuration. 41 patients with a grade I or II open, nonoperative fracture secondary to a low-velocity bullet were treated with 1gm of cefazolin administered in the emergency room and a 7-day course of oral cephalexin. No patient developed a deep infection. Thus, local I&D, tetanus, and oral antibiotics for 2-3 days is adequate for low velocity gunshot wounds.
Which clinical sign is the most sensitive for the diagnosis of compartment syndrome in a child with a supracondylar humerus fracture?
pulselessness
pallor
paresthesia
paralysis
increasing analgesia requirement Correct answer: 5
Although pain, pallor, paresthesia, paralysis, and pulselessness are all possible signs and symptoms of compartment syndrome in children with fractures, studies have shown increasing analgesia requirement is more sensitive.
Bae et al reviewed thirty-six cases of compartment syndrome in 33 pediatric patients. Approximately 75% of these patients developed compartment syndrome in the setting of fracture. "They found pain, pallor, paresthesia, paralysis, and pulselessness were relatively unreliable signs and symptoms of compartment syndrome in these children. An increasing analgesia requirement in combination with other clinical signs, was a more sensitive indicator of
compartment syndrome."
Whitesides et al summarizes the diagnosis and treatment of acute compartment syndrome. They emphasize the need for early diagnosis, as "muscles tolerate 4 hours of ischemia well, but by 6 hours the result is uncertain; after 8 hours, the damage is irreversible." They recommend fasciotomy be performed when tissue pressure rises past 20 mm Hg below diastolic pressure.
A 45-year-old man sustains the injury seen in Figures A and B following a motor vehicle accident. Postoperative radiographs are seen in Figures C and D. Which of the following is the most accurate when comparing outcomes between intramedullary nailing (IMN) and open reduction internal fixation (ORIF) for this injury?

Union rates at one year are higher with ORIF
Infection rates are higher with IMN
Functional shoulder outcomes at one year are equivalent with IMN and ORIF
Iatrogenic radial nerve injury rate is higher with ORIF
Shoulder stiffness rates at one year are equivalent with IMN and ORIF Correct answer: 3
Although shoulder pain and stiffness is increased following IMN compared to ORIF, functional outcome scores at one year have been shown to be equivalent
in both treatment groups.
Diaphyseal humeral shaft fractures outcomes following IMN and ORIF are under further investigation. Diaphyseal humeral shaft fractures have historically been treated with ORIF, however proponents for IMN cite benefits of less periosteal stripping and soft tissue dissection. Recent investigations have shown outcomes with regard to nonunion, infection, re-operation, and nerve palsy appear equivalent between both groups. Rates of shoulder stiffness and shoulder pain have been demonstrated to be higher in IMN compared to ORIF. American Shoulder and Elbow Scores (ASES) have shown no difference at one year post-operatively.
Bhandari et al. performed a meta-anaylsis of 3 prospective randomized trials. They found lower rates of re-operation and shoulder impingement with ORIF of humeral shaft fractures.
Wali et al. performed a prospective randomized study of IMN or ORIF on 50 patients with mid-diaphyseal humeral shaft fractures. They found IMN had shorter operative time, shorter hospital stay, and lower blood loss. They found no difference in union rates, complication, or shoulder functional outcomes scores. They conclude IMN to be an effective option for treating mid-diaphyseal humeral shaft fractures.
Heineman et al. have recently conducted an update on their meta-analysis to include more recent randomized studies. With the inclusion of newer studies the author found a statistically significant increase in total complication rate with the use of IM nailing compared with ORIF. The authors found no significant difference between the two treatment modalities for the secondary outcomes (nonunion, infection, nerve palsy, re-operation).
Figures A and B show a diaphyseal humeral shaft fracture. Figure C and D show postoperative radiographs following intramedullary nailing of a humeral shaft fracture.
Incorrect Answers:
A 25-year-old female presents complaining of progressive anteromedial pain in her left ankle. She underwent operative fixation 5 months prior at an outside hospital. The operative report indicated that, due to anterior fracture blisters, a direct medial incision was utilized, centered over the posterior colliculus of the medial malleolus, without violation of the deltoid ligament. A radiograph and computed tomographic scan of her initial injury are shown in Figures A and B, respectively. On exam, she has well-healed incisions, exhibits no tenderness to palpation over her hardware, but does endorse pain with deep palpation along the anteromedial joint line. Figure C shows an anteroposterior left ankle radiograph taken today. Labs are obtained and reveal a white blood cell count of 9.0 k/uL (reference range 4.5-11.0 k/uL) and a C-reactive protein value of 0.8 mg/dL (<0.9 mg/dL). What is the next best step in managing her problem?

Syndesmotic fixation
Intra-articular corticosteroid injection
Referral to physical therapy
Surgical correction of malunion
Removal of hardware Correct answer: 4
This patient sustained a supination-adduction (SAD) injury with a vertical shear fracture of her medial malleolus and a fibular avulsion fracture. She sustained a medial plafond articular impaction injury that was not addressed at the time of surgery.
In SAD injuries, supination of the foot is combined with inward rotation at the ankle, adduction of the hindfoot, and inversion of the forefoot. This results in the following sequence of events: 1. Talofibular sprain or distal fibular avulsion (equivalent to Weber A). 2. Vertical medial malleolus fracture as the talus strikes the tibia. Associated injuries may include osteochondral damage to the talus and marginal impaction of the medial plafond. It is important to evaluate the medial plafond for articular impaction. When present, an arthrotomy must be performed, typically utilizing an anteromedial incision, with direct visualization of the articular surface to restore the joint line appropriately.
Weber et al. provided a review article on corrective osteotomies for malleolar fracture malunions. They stress that malunions can lead to ankle instability, abnormal load transfer, and post-traumatic arthritis. They conclude that corrective osteotomies that restore anatomical alignment show good results in long-term follow-up.
Perera et al. provided additional commentary on the surgical reconstruction of malunited ankle fractures. The authors emphasize the link between malunion and poor outcomes. They state that successful salvage procedures involve a clear understanding of the deformity, careful preoperative planning, and a solid understanding of reconstructive techniques. They provide several instructive case examples in their review.
McConnell et al. provided a discussion on SAD ankle fractures at their institution and emphasized the importance of recognizing marginal impaction of the tibial plafond when treating these injuries. Of 800 ankle fractures identified over a 5-year period, 44 were SAD injuries, 19 of the 44 displayed a vertical shear fracture of the medial malleolus, and 8 of the 19 demonstrated marginal impaction of the tibial plafond. These 8 impaction injuries were treated with open reduction internal fixation with elevation of the articular impaction; all had good to excellent outcomes without arthritic changes at last
follow-up.
Figure A is an anteroposterior left ankle radiograph demonstrating a SAD injury with a vertical shear fracture of the medial malleolus, a fibular avulsion fracture, and articular impaction of the medial tibial plafond. Figure B is a coronal CT demonstrating articular impaction of the medial plafond. Illustration A is an intra-operative photograph with the medial malleolus retracted allowing inspection of the articular surface; mild anteromedial plafond impaction is present.
Incorrect Answers:

A 90-year-old female slips and falls at home. She is a community ambulator and has no medical problems. She reports right hip pain at this time. Injury radiographs are shown in Figures A & B. Delay of more than 48 hours may result in:

Increased intraoperative time
Increased 30-day mortality
No impact on the rate of postoperative pneumonia
Higher rates of blood transfusion
Increased risk of post-operative infection Correct answer: 2
Figures A & B demonstrate a right, unstable intertrochanteric femur fracture. Surgical stabilization within 48 hours improves short-term and 30-day mortality.
Hip fractures are common and mortality rates vary. In the elderly, mortality rates may reach 10% at 1-month, 20% at 4-months, and 30% at 1-year. Time to surgery has found to be a decisive factor. A pre-operative delay may lead to an increase in mortality and adversely influence other clinical outcomes.
Clinical guidelines recommend immediate operative stabilization, given the patient is medically fit for surgery.
Nyholm et al. performed a retrospective study of the Danish Fracture Database to investigate whether a surgical delay increases 30-day and 90-day mortality rates for patients with proximal femoral fractures. The 30-day and 90-day mortalities were 10.8% and 17.4%, respectively. The risk of 30-day mortality increased with increasing time intervals of more than 12 hours, 24 hours, and more than 48 hours. 90-day mortality increased with a surgical delay of more than 24 hours. They conclude that rapid surgical treatment should be performed by attending orthopaedic surgeons.
Moja et al. performed a meta-analysis and meta-regression to assess the relationship between surgical delay and mortality in elderly patients with a hip fracture. They analyzed 35 independent studies with 191,873 patients and 34,448 deaths. The majority of studies had a cut-off of 48 hours. They report that early hip surgery was associated with a lower risk of death and pressure sores. They conclude that early hip fracture surgery appears to provide a survival benefit compared to later intervention.
Rodriguez-Fernandez et al. performed a study examining 2 groups with hip fractures. The first group was studied retrospectively and had an average delay of surgical treatment of more than 1-week while the second group was studied prospectively, and had surgical treatment within 48 hours. They found a larger number of complications in the group with a delay in surgical treatment. They conclude that elderly patients with hip fractures should be treated as soon as their medical condition permits.
Figures A and B are the AP and lateral radiographs demonstrating a right, unstable intertrochanteric femur fracture. Illustration A is an intertrochanteric femur fracture, stabilized with a cephalomedullary nail.
Incorrect Answers:

A 22-year-old healthy left hand dominant male presents to the ED with left shoulder pain after falling from an ATV. Figure A is the radiograph of his left clavicle. He is neurovascularly intact and there is no evidence of skin tenting or open fracture. Which of the following most predisposes this patient to nonunion?

Diaphyseal fracture
Fracture displacement
Age
Male Gender
Injury involving the dominant extremity Correct answer: 2
Displaced clavicle fractures are associated with higher rates of nonunion.
Nonunion occurs in roughly 5-6% of clavicle fractures and can result in slower functional return, poor cosmesis and muscle fatigability. Clavicle fractures can be sub-classified using the Allman classification into medial, diaphyseal, and lateral injuries (Illustration A). The Neer classification for diaphyseal injuries describes fractures as "nondisplaced" (less than 100% displacement) and "displaced" (greater than 100% displacement).
Robinson et al. performed a prospective cohort study to identify risk factors for nonunion after nonoperative management of clavicle fractures. The overall nonunion rate was 6.2% and was highest in lateral third fractures (11.5%).
Diaphyseal fractures had the lowest nonunion rate (4.5%). Additionally, the authors found that the risk for nonunion was increased by advancing age, female gender, fracture displacement, and comminution.
Jorgensen et al. performed a systemic review of the literature looking for predictors of non-union and malunion in mid shaft clavicle fractures treated non-operatively. They found fracture comminution, displacement, older age, female gender, and the presence of smoking to be his factors for non-union. Of these, displacement was the most likely factor that can be used to predict nonunion.
Figure A demonstrates a displaced left clavicle diaphyseal fracture. Note that the medial fragment is displaced superiorly by the deforming force of the sternocleidomastoid. Illustration A represents the Allman classification.
Illustration B demonstrates the deforming forces acting on the clavicle.
Incorrect Answers:

A 24-year-old male presents with ankle pain after being involved in a motor vehicle accident. His injury radiograph is shown in Figure A. Which of the following has been shown to contribute to the development of post-traumatic arthritis in this injury pattern?

Initial superficial zone cartilage cell death via apoptosis at the fracture margins
Initial superficial zone cartilage cell death via apoptosis remote from the fracture margins
Initial superficial zone cartilage cell death via necrosis remote from the fracture margins
Initial superficial zone cartilage cell death via necrosis at the fracture margins
Delayed superficial zone cartilage cell death via necrosis at the fracture margins
Figure A demonstrates a tibial plafond fracture. Initial superficial zone cartilage cell death via necrosis at the fracture margins has been shown to contribute to post-traumatic arthritis.
Post-traumatic osteoarthritis typically occurs after an intra-articular fracture. Impacted chondrocytes die by either necrosis or apoptosis, which have both been implicated in post-traumatic osteoarthritis. Initial cell death in the superficial cartilage zones at the fracture margins occurs by necrosis. Apoptosis occurs in a delayed fashion and is mitigated by several bioactive agents.
Apoptosis also affects the superficial cartilage zones near the fracture margins. Deep cartilaginous zones and areas away from the fracture margins do not seem to be involved in these processes.
McKinley et al. performed a review of the basic science of intra-articular fractures and posttraumatic osteoarthritis. They report that initial damage to the cartilage in combination with the ensuing pathomechanical and pathobiologic response of the cartilage after a fracture contribute to posttraumatic arthritis. Chronic abnormal joint loading is also thought to contribute to this process as well. They conclude that the relative contribution of each is unknown.
Tochigi et al. performed a study to determine the distribution and progression of chondrocyte damage after intra-articular ankle fractures. They harvested 7 normal human ankles and subjected them to impaction. They found that immediate superficial zone chondrocyte death was greater in fracture-edge regions than on-fracture regions. Subsequent cell death over the next 48 hours was significantly higher in fracture-edge regions as well. They conclude that cartilage damage in intra-articular fractures was characterized by chondrocyte death at fracture margins.
Figure A is an ankle mortise radiograph demonstrating an intra-articular tibial plafond fracture.
Incorrect Answers:
A 35-year-old male presents with left knee pain after sustaining the injury seen in Figure A. He is neurovascularly intact and can perform a straight leg raise, but has pain with passive range of motion. Figures B and C show an anteroposterior and lateral radiograph of the left knee, respectively. 175 cc of saline is injected into the superolateral quadrant with no egress of fluid from the inferolateral
laceration. What percentage of traumatic arthrotomies would be detected with this test?

Question 8

A 6-year-old girl is referred for the elbow injury seen in Figure 2. What is the most appropriate treatment?

Explanation

DISCUSSION: The patient has a displaced lateral condyle fracture; therefore, simple immobilization for 3 to 8 weeks is likely to result in malunion or nonunion. Closed reduction of such injuries is rarely successful. The fracture is unstable, so fixation is required after open reduction. Because the fixation must cross the physis, smooth pins are indicated for the skeletally immature elbow. Open reduction with fixation has been shown to reduce the risk of delayed union and malunion.
REFERENCES: Beaty JH, Kasser JR: The elbow: Physeal fractures, apophyseal injuries

of the distal humerus, avascular necrosis of the trochlea, and T-condylar fractures, in Beaty JH, Kasser JR (eds): Fractures in Children, ed 5. Philadelphia, PA, Lippincott Williams & Wilkins, 2001, pp 625-703.
Rutherford A: Fractures of the lateral humeral condyle in children. J Bone Joint Surg Am 1985;67:851-856.
Hasler CC, von Laer L: Prevention of growth disturbances after fractures of the lateral humeral condyle in children. J Pediatr Orthop B 2001;10:123-130.

Question 9

The radiograph shown in Figure 54 reveals that the plate on the second metacarpal is acting in what manner?

Explanation

DISCUSSION: There are four ways in which a plate acts: compression, tension bend, bridge or spanning, and buttress. Since there is no cortical contact with the large span of comminution, this plate is acting as a bridge plate. A bridge plate is defined as when the plate is used as an extramedullary splint attached to the two main fragments, leaving the comminution untouched.
REFERENCE: Ruedi T, Murphy WM (eds): AO Principles of Fracture Management. New York, NY, Thieme, 2000, p 221.

Question 10

A college basketball player is struck in the eye by a player’s hand while driving to the basket. Fluorescein evaluation reveals the injury shown in Figure 18. Management should consist of

Explanation

DISCUSSION: The athlete has a corneal abrasion. Fluorescein staining identifies the break in the epithelium when examined with ultraviolet light. Topical antibiotics are used as prophylaxis against secondary bacterial infection, and the patch, applied with the lid closed, is used for comfort and to promote epithelial healing. The accompanying symptoms, including pain, tearing, and photophobia, are usually too intense to allow a return to play. Surgery is reserved for a corneal laceration with associated loss of the anterior chamber. While a proper fundoscopic examination may be a consideration, increased intraocular pressure is not typically associated with this injury. Traumatic hemorrhage in the anterior chamber (hyphema) necessitates strict bed rest during the early phases of healing; examination will most likely reveal the red fluid level of blood settling inferiorly in the anterior chamber. It is often associated with increased intraocular pressure.
REFERENCES: Brucker AJ, Kozart DM, Nichols CW, et al: Diagnosis and management of injuries to the eye and orbit, in Torg JS (ed): Athletic Injuries to the Head, Neck, and Face. St Louis, MO, Mosby-Year Book, 1991, pp 650-670.
Zagelbaum BM: Treating corneal abrasions and lacerations. Phys Sports Med 1997;25:38-44.

Question 11

Excision of heterotopic bone about the forearm or elbow can be done with limited recurrence rates as early as which of the following after initial injury?

Explanation

DISCUSSION: Excision of heterotopic bone about the elbow and forearm was classically treated once the bone was mature and no further bone development was occuring (bone scan became negative). However, several studies have shown that earlier removal before this point in time is safe, when done in conjunction with radiation therapy (XRT).
The referenced study by McAuliffe et al is a retrospective review of heterotopic ossification (HO) about the elbow followed by 100 cGY (5 fractions over 1 week) of XRT as early as 3 months post-injury. They were able to achieve an average arc of motion > 100 degrees.
The other referenced study by Beingessner et al is a review of HO excision of the forearm. They found that excision and XRT, followed by 6 weeks of indomethacin, led to an increase of forearm motion from an average of 17 degrees to 136 degrees when the excision was done at 4 months post-injury.

Question 12

Which of the following is most associated with local recurrence of the lesion seen in the radiograph and MRI scan shown in Figures 27a and 27b?

Explanation

DISCUSSION: The lesion is an aneurysmal bone cyst. These lesions are known to have a local recurrence rate of 5% to 50%. Young age, open physes, stage, and type of surgical removal and resulting margin have all been shown to affect the recurrence rate. Chemotherapy is not used in the treatment of aneurysmal bone cysts.
REFERENCES: Gibbs CP Jr, Hefele MC, Peabody TD, et al: Aneurysmal bone cyst of the extremities: Factors related to local recurrence after curettage with a high-speed burr. J Bone Joint Surg Am 1999;81:1671-1678.
Vergel De Dios AM, Bond JR, Shives TC, et al: Aneurysmal bone cyst: A clinicopathologic study of 238 cases. Cancer 1992;69:2921-2931.

Question 13

A 7-year-old boy is seen in the emergency department with an isolated and displaced supracondylar humerus fracture and absent radial and ulnar pulses. Despite a moderately painful attempt at realignment, examination reveals that his hand remains pulseless. What is the next most appropriate step in management? Review Topic

Explanation

Displaced supracondylar humerus fractures in children may have associated vascular compromise. Decreased blood flow may be due to vessel injury, entrapment within the fracture site, kinking from fracture displacement, or from vessel spasm. Optimal initial treatment in the emergency department includes gentle realignment of the limb
and vascular assessment. Angiography is not required in isolated injuries as the level of the vessel compromise is always at the site of the fracture. When blood flow is not restored, the next best step in treatment is to proceed urgently to the operating room. A formal closed reduction and pinning is performed, and then the vascular status is reassessed. Exploration and vascular repair is required if the hand is cool, white, and without pulses.

Question 14

Integrins function in which of the following ways?

Explanation

Integrins are groups of molecules essential for osteoclast attachment to the bone surface.
Integrins are a large family of heteromeric cell surface receptors composed of non-covalently bound alpha and beta subunits which interact with extracellular matrix molecules, serum constituents and various adhesion molecules. Specifically, aVß3 is a type of integrin found on osteoclasts that attaches to bone by coupling with vitronectin.
Bikle reviews the cause of bone loss during periods of unloading. They state the during periods of rest, integrin expression is decreased, leading to disuse osteoporosis. They argue that drugs that selectively regulate the integrin signaling pathway may
reverse bone loss during periods of disuse.
Illustration A shows an example of an osteoclast attaching to bone via the integrin aVß3.
Incorrect
1:
This
is
the
function
of osteocytes.
2:
This
is
the
function
of osteoblasts.
3:
This
is
the
function
of
osteoprogenitor cells.

Question 15

An obese 4-year-old boy has infantile Blount’s disease. Radiographs reveal a metaphyseal-diaphyseal angle of 18 degrees and a depression of the medial proximal tibial physis. Management should consist of

Explanation

DISCUSSION: The deformity is too severe for observation, and at age 4 years, the child is too old for orthotic treatment. To prevent recurrence, surgery should be performed before irreversible changes occur in the medial physis. A proximal tibial osteotomy should overcorrect the mechanical axis to 10 degrees of valgus. Bar resection has not been shown to be as effective in this severe deformity, especially without a concomitant osteotomy.
REFERENCES: Raney EM, Topoleski TA, Yaghoubian R, Guidera KJ, Marshall JG: Orthotic treatment of infantile tibia vara. J Pediatr Orthop 1998;18:670-674.
Loder RT, Johnston CE: Infantile tibia vara. J Pediatr Orthop 1987;7:639-646.

Question 16

In a fatigue test, the maximum stress under which the material will not fail, regardless of how many loading cycles are applied, is defined as

Explanation

Fatigue failure occurs with repetitive loading cycles at stress below the ultimate tensile strength. Fatigue failure depends on the magnitude of the stress and number of cycles. If the stress is less than a predetermined amount of stress, called the endurance limit, the material may be loaded cyclically an infinite number of times without breaking.

Question 17

Figures 27a through 27c show the AP radiograph, MRI scan, and biopsy specimen of an otherwise healthy man who has a painful wrist. Serum chemistry studies are normal. What is the most likely diagnosis?

Explanation

DISCUSSION: The osseous sites most frequently involved by giant cell tumor of bone are the distal femur, proximal tibia, and distal radius with approximately 10% of giant cell tumors involving the distal radius. The goals of treatment are to remove the tumor completely and to preserve maximum function of the extremity.
REFERENCE: Vander Griend RA, Funderburk CH: The treatment of giant-cell tumors of the distal part of the radius. J Bone Joint Surg Am 1993;75:899-908.

Question 18

A 74-year-old woman with rheumatoid arthritis reports shoulder pain that has failed to respond to nonsurgical management. AP and axillary radiographs are shown in Figures 23a and 23b. Examination reveals active forward elevation to 120 degrees and external rotation to 30 degrees. What treatment option results in the most predictable pain relief and function?

Explanation

DISCUSSION: Most studies have shown that total shoulder arthroplasties yield better pain relief and improved forward elevation when compared to hemiarthroplasty in patients with rheumatoid arthritis. Although rotator cuff tears are more common in this patient population, this patient has good forward elevation and no significant superior migration of the humeral head; therefore, a reverse arthroplasty is not indicated. The arthritis is too advanced in this patient to consider arthroscopy, but in less advanced cases it can improve range of motion and decrease pain. Metal-backed glenoid components have shown higher rates of loosening.
REFERENCES: Collin DN, Harryman DT II, Wirth MA: Shoulder arthroplasty for the treatment of inflammatory arthritis. J Bone Joint Surg Am 2004;86:2489-2496.
Baumgarten KM, Lashgari CM, Yamaguchi K: Glenoid resurfacing in shoulder arthroplasty: Indications and contraindications. Instr Course Lect 2004;53:3-11.
Martin SD, Zurakowski D, Thornhill TS: Uncemented glenoid component in total shoulder arthroplasty: Survivorship and outcomes. J Bone Joint Surg Am 2005;87:1284-1292.

Question 19

What is the standard interval for placement of an anterolateral portal in ankle arthroscopy?

Explanation

As with arthroscopy of the knee, the anterolateral (AL) portal is the primary diagnostic portal used for initial placement of the arthroscope. The AL portal is made 5 mm below the joint line just lateral to the extensor tendons. The lateral cutaneous branch of the superficial peroneal nerve lies near this portal region. From this approach, one can visualize the anteromedial (AM), anterocentral (AC), and most of the AL areas of the tibiotalar joint. With the addition of laterally based external distraction instrumentation, the surgeon can usually advance the arthroscope posterocentrally and posterolaterally to visualize most of the articulation and the structures in the central and posterior compartments: the intraarticular aspects and synovium of the distal tibiofibular syndesmosis, the posterior tibiofibular ligament, the transverse ligament, and the synovial plicae that overlie the transverse ligament.

Question 20

A 52-year-old, right hand dominant man comes for evaluation of right shoulder pain that has been intermittently bothering him for three months. The pain is worse with overhead activities. He denies any history of trauma. His range of forward elevation in the plane of the scapula is painful and is limited to 145 degrees, compared to 170 degrees on his unaffected side. A radiograph is shown in Figure A. He saw another orthopedist a month ago, who ordered an MRI, which showed a small, partial thickness supraspinatus tendon tear. He received a subacromial injection of lidocaine at that time which temporarily relieved 90 percent of the pain he felt with passive forward elevation of his shoulder past 90 degrees. Today he is requesting a subacromial injection of platelet rich plasma (PRP). You tell him that with regard to pain, function and range of motion, subacromial injection of PRP: Review Topic

Explanation

At one year, quality of life, pain, disability and shoulder range of motion are the same for patients treated with therapy and placebo versus patients treated with therapy and
PRP injection.
Platelet rich plasma has been used for the treatment of chronic tendinopathy in different areas with mixed results. No benefit to patients with symptoms of subacromial impingement has been demonstrated for subacromial injection of PRP, when added to a standard therapy program.
Kesikburun et al. conducted a randomized controlled trial in which patients with rotator cuff tendinopathy or partial rotator cuff tears were randomized to receive ultrasound-guided subacromial injection of either PRP or lidocaine, followed by a standard six-week therapy program. The authors found no difference in pain, range of motion or validated outcome scores at one year follow up.
Hall et al. reviewed sports medicine applications for PRP. At that time (2009), with regard to PRP, they concluded that there was "little clinical evidence for its use."
Ketola et al. sought to determine the effectiveness of subacromial decompression for the treatment of subacromial impingement syndrome. They randomized 140 patients to a supervised exercise program or arthroscopic subacromial decompression followed by a supervised exercise program. They found no clinically important differences between the two groups at 24 months follow up.
Figure A shows a right shoulder radiograph without osseous pathology. Incorrect answers:

Question 21

In an isolated ankle syndesmotic injury, the fibula is unstable in the incisura fibularis of the tibia. In what direction is the fibula most unstable?

Explanation

DISCUSSION: In an ankle syndesmosis injury, the fibula is most unstable in an anterior and posterior direction. This is whether or not there is an accompanying ankle fracture. Most commonly, the fibula will subluxate anterior in an ankle fracture model.
The first referenced article by Xenos et al found that stress lateral radiographs have more interobserver reliability than stress AP/mortise radiographs and that two syndesmotic screws are stronger than one.
The referenced article by Candal-Couto et al is a biomechanical study that found more anterior-posterior instability in a syndesmosis injury model, and more ankle instability is noted with syndesmosis injury and a concomitant deltoid injury. The referenced article by Zalavras et al is an excellent review article on ankle syndesmosis injuries.

Question 22

A 52-year-old man underwent arthroscopic repair of a 1-cm supraspinatus tendon tear 3 weeks ago. He was doing well until he fell down three stairs. One week after the fall he continues to report pain similar to his preoperative pain. An MRI scan reveals a minimally retracted 1-cm supraspinatus tendon tear in the same location as his original tear. Management should now consist of Review Topic

Explanation

The patient has retorn his rotator cuff repair. This traumatic retear is different from a chronic tear and should be treated similar to an acute rotator cuff tear. Because the patient is younger than age 65 and has a small, single tendon tear, a revision rotation cuff repair is indicated with an expected tendon healing rate of greater than 95%. A physical therapy program is not indicated, and further delay in repair compromises his functional recovery. A cortisone injection is not indicated for this repairable tendon tear. Immobilization will not allow the tendon to heal once it has retorn. A debridement procedure is not indicated on this repairable tendon tear; this procedure is indicated in painful, chronic, irreparable tendon tears.

Question 23

This reporting avoids a ceiling and floor effect, where most of the respondents score either at the top or the bottom of the assessment scale.

Explanation

Which of the following statistical tools is used to determine responsiveness?
The only accurate statement is that, at 1 month, patients in group 3 are more likely to live longer than patients in group 1 and 2.
The Kaplan-Meier curve is a statistical method used in survivorship analysis to estimate survival rates at different time points. The horizontal axis depicts the time points and the vertical axis depicts the probability of survival. At a given time point, greater survivorship is demonstrated by higher values on the vertical axis.
Kocher et al. reviewed clinical epidemiology and biostatistics relevant in orthopaedic
surgery. They reported that survivorship data are typically analyzed with use of the Kaplan-Meier method. This analysis is used when the actual date of the end point is known. A survivorship curve can be plotted to illustrate the percentage of patients still alive after the intervention.
Petrie et al. reviewed statistics, terminology and the principles involved in simple data analysis, and outlines areas of medical statistics that have gained
prominence in recent years in orthopaedic papers. The authors provide an insight into some of the more common errors that occur in published orthopaedic journals and which are frequently encountered at the review stage in papers submitted to the Journal of Bone and Joint Surgery.
Figure A depicts a Kaplan-Meier curve for 3 groups of patients undergoing 3 different interventions.
Incorrect Answers:
When evaluating patient-reported outcomes in spine surgery, the Patient- Reported Outcomes Measurement Information System (PROMIS) has been found to have what differences compared to other assessment tools?
Communication failures have been associated with increased treatment costs, increased complications, and delays in patient care.
The leading cause of medical errors, wrong-site surgeries, diagnostic delays and loss to follow-up is attributed to communication errors. Studies have shown that this directly leads to increased complications, increased treatment costs, and delays in patient care. In the surgical setting, the performance of the pre-surgical time-out affords clarification of the treatment plan, confirmation of the procedure and site, and an opportunity for the team to address any concerns.
Weller et al. reviewed barriers to effective teamwork in healthcare delivery. They found that effective communication across all team members, inclusive training, and the creation of democratic teams can reduce treatment delays and minimize complications. They concluded that all team members should have a shared understanding of the situation when involved in patients care.
Lingard et al. performed a prospective study determining the feasibility of a preoperative 10-item checklist discussion including nurses, surgeons, and anesthesiologists. They reported that the discussion usually took place prior to bringing the patient to the OR and took on average 3.5 minuted. Overall, the guided discussion was very well received by participants and provided an opportunity to inform providers of the patient's information to address potential problems. The authors cited that variations in workflow patterns as a potential barrier to widescale implementation of the checklist discussion.
Incorrect answers:
The outcomes of three novel interventions are investigated and the preliminary results are depicted in Figure A. Which of the following statements is most accurate?
Linezolid acts to inhibit protein synthesis by preventing the formation of the initiation complex between the 30S and 50S subunits of the ribosome.
Linezolid is a type of oxazolidinone, a relatively newer class of antibiotics that are active against multidrug-resistant staphylococci, streptococci, and enterococci. Although many antimicrobial agents affect or disrupt protein synthesis in bacteria, linezolid is unique in that it disrupts protein synthesis at its origin rather than later in the cascade. It achieves this by binding to the
50S subunit of the bacterial ribosome, preventing the formation of the initiation complex.
Swaney et al. performed a study to investigate the mechanism of action of linezolid. They found that linezolid inhibits the formation of the initiation complex in bacterial translation systems by preventing the formation of the N- formylmethionyl-tRNA-ribosome-mRNA ternary complex.
Thompson et al. performed a study on the efficacy of various antibiotics in treating periprosthetic joint infections (PJI). They administered oral linezolid with or without oral rifampin, intravenous vancomycin with oral rifampin, intravenous daptomycin or ceftaroline with or without oral rifampin, oral doxycycline, or sham treatment at human- exposure doses for 6 weeks in a mouse model of PJI. They found that oral-only linezolid-rifampin and all intravenous antibiotic-rifampin combinations resulted in no recoverable bacteria and minimized reactive bone changes. Additionally, although oral linezolid was found to be the most effective monotherapy, all oral and intravenous antibiotic monotherapies failed to clear infection or prevent reactive bone changes.
They concluded that the oral-only linezolid-rifampin option might reduce venous access complications and health-care costs.
Illustration A is a diagram depicting the mechanism of action of various antibiotics.
Incorrect Answers:
50S subunit of the bacterial ribosome, preventing protein chain elongation by inhibiting peptidyl transferase activity of the ribosome.
elongation by blocking aminoacyl translocation.
Failure of effective communication in the surgical setting has been associated with what?
Unfractionated heparin works in the coagulation cascade by promoting the ability of antithrombin III to inhibit factors IIa, III, Xa.
Heparin works by binding to and enhancing the ability of antithrombin III to inhibit factors IIa, III, Xa. It is metabolized by the liver. The risks associated with the use of unfractionated heparin include bleeding and heparin induced thrombocytopenia (HIT). The reversal agent is protamine sulfate.
Agnelli et al. reviewed direct thrombin inhibitors for the prevention of VTE after major orthopaedic surgery. They reported widespread use, however, limitations in the use of unfractionated heparin and low-molecular-weight heparins. They highlighted that direct thrombin inhibitors (Ximelagatran) inactivate thrombin without requiring any plasma cofactor, inhibit both free
and fibrin-bound thrombin, and do not appreciably bind to plasma proteins. They concluded that the features of rapid absorption, conversion, bioavailability, low variability, dose-time, food independency, and the predictable anticoagulant activity make direct thrombin inhibitors an attractive antithrombotic agent especially for prolonged out-of hospital prophylaxis.
Kwong et al. reviewed the efficacy and safety of fondaparinux, a selective factor Xa inhibitor and reported its efficacy and safety in 4 phase III clinical trials. They reported fondaparinux usage resulted in an overall 55% decrease in the risk of venous thromboembolism (VTE) relative to the low-molecular- weight heparin enoxaparin without increasing the incidence of clinically relevant bleeding, which was similarly low for both agents. They concluded
that the superior efficacy of fondaparinux relative to enoxaparin is the result of its unique mechanism of action, clinical pharmacology.
McLynn et al. investigated the risk factors and chemoprophylaxis for VTE in elective spine surgery. They reported that independent risk factors for VTE included greater age, male gender, increasing body mass index, dependent functional status, lumbar spine surgery, longer operative time, perioperative blood transfusion, longer length of stay, and other postoperative
complications. The majority of patients received unfractioned heparin and they observed this did not significantly influence the rate of VTE, but was associated with a significant increase in hematoma requiring a return to the operating room. They concluded that there is insufficient evidence to support the routine use of chemoprophylaxis in low-risk patients, and recommended full consideration of risks and benefits after elective spine surgery.
Figure A depicts the coagulation cascade, with the factor circled in red (IIa) being the target of unfractionated heparin, through its effect on antithrombin III.
Incorrect Answers:
Which of the following antibiotics acts to inhibit protein synthesis by preventing the formation of the initiation complex between the 30S and 50S subunits of the ribosome?
Acetaminophen inhibits prostaglandin E2 production through its effect on interleukin-1 beta. It exerts its effects on the central nervous system.
Multimodal pain management has become an increasingly important consideration in total joint arthroplasty recovery, namely in regard to minimizing opioid requirements while optimizing pain control and patient satisfaction. Given the negative side effects and increasing scrutiny on narcotic use, modalities that help to decrease post-operative narcotic requirements have become a major focus and include nonsteroidal anti- inflammatories, selective COX-2 inhibitors, gabapentinoids, local anesthetic blocks, and acetaminophen. Acetaminophen acts directly the central nervous system, providing both pain relief and antipyretic effects. It does so by inhibiting prostaglandin E2 production through the blockade of interleukin-1 beta.
Jinnah et al. performed a comparison of two multimodal pain regimens used for postoperative pain control in total joint arthroplasty patients. They hypothesized that using a multimodal pain protocol focusing on periarticular injections including liposomal bupivacaine would have improved results when compared with a parenteral opioid- based regimen. They found a decrease in length of stay and rate of discharge to skilled nursing facilities with the implementation of a novel multimodal protocol. They concluded that a multimodal approach inclusive of periarticular injection can lead to a reduced
length of stay.
Politi et al. performed a prospective randomized trial comparing the use of intravenous versus oral acetaminophen in total joint arthroplasty. They found that IV acetaminophen did not provide a significant difference in pain relief except within the first 0-4 hours. They concluded that IV acetaminophen does not provide a significant benefit when compared to the oral form, which is also less expensive.
Incorrect Answers:
Which of the following agents results in blood anticoagulation by exerting inhibitory effects on the factor circled in the color red in Figure A?
Based on the stress-strain curve in Figure A, ceramic has the highest modulus of elasticity.
Young's modulus is a measure of the stiffness (ability to resist deformation) of a material in the elastic zone that is calculated by measuring the slope of the stress-strain curve in the elastic zone. A higher modulus of elasticity indicates a stiffer material. Relative values of Young's modulus include: (1) ceramic, (2) alloy, (3) stainless steel, (4) titanium, (5)
cortical bone, (6) matrix polymers, (7) PMMA, (8) polyethylene, (9) cancellous bone, (10) tendon/ligaments, and (11) cartilage.
Lang et al. published a review on the use of ceramics in total hip replacement. They report that properties of ceramic which make it particularly attractive for this application include its hardness, high compression strength, and excellent wettability. However, its low fracture toughness and linear elastic behavior make it prone to breakage under stress.
Figure A is a stress-strain curve, the slope of which is used to determine Young's modulus.
Incorrect Answers:
Which of the following medications work by inhibiting prostaglandin E2 production through interleukin-1 beta?
A power analysis determines the minimum number of patients needed in a study to show a clinically significant difference. It should be performed before starting the study.
Power is the probability of finding a significant association if one truly exists. It is defined as 1 minus the probability of a type 2 error (beta) and is generally set to 80% meaning that we are willing to accept a 20% chance of a type 2 error. A power analysis will determine the minimum number of patients that shows a clinically significant difference. The minimum number of patients should be determined prior to initiating a study. Calculation of power after a study has been completed is controversial and discouraged.
Vavken et al. performed a review on the management of confounding in controlled orthopaedic trials. They report that confounding occurs when the effect of exposure of an outcome is distorted by a confounding factor and will lead to spurious effect estimates in clinical studies. They performed a cross- sectional study of a sample of controlled trials reported in the orthopaedic literature in 2006. They conclude that only 30 studies reported that the had a power analysis performed.
Kocher et al. performed a review of clinical epidemiology and biostatistics as a primer for orthopedic surgeons. They report that a power analysis should be performed prior to initiating the study. This will ensure the study is appropriately powered and decrease the effects of chance. They conclude that when a study determines no significant effect the power of the study should be reported.
Incorrect Answers:
Based on the stress-strain curve in Figure A, which of the following materials has the highest modulus of elasticity?
The World Health Organization (WHO) defines osteopenia as a bone mineral density (BMD) that is between 1 and 2.5 standard deviations below young normal (T-score of - 1 to -2.5).
The WHO defines osteopenia as decreased BMD without fracture risk. Osteopenia is defined as a T-score of 1 to 2.5 standard deviations below young normals (-1 to -2.5), while osteoporosis is defined as a T-score of more than

Question 24

Which of the following statements is true regarding the superomedial fragment of an intra-articular calcaneus fracture?

Explanation

DISCUSSION: The superomedial fragment of a intra-articular calcaneus fracture is also referred to as the sustentacular fragment or “constant fragment” (Illustrations A, B). In their CT analysis of acute calcaneal fractures, Gilmer et al describe that the superomedial piece typically does not move in these fractures due to its strong ligamentous attachments to the talus. For this reason, it is commonly referred to as the "constant fragment." The superiomedial fragment is important during ORIF of calcaneal fractures, because fixation from the lateral side is typically based off this "constant" fragment as a guide to provide anatomic fixation. Additionally, the flexor hallucis longus (FHL) tendon wraps inferiorly around this piece within an osseus groove (illustration C). Illustration D shows the classification and position of these fractures.

Question 25

Figures 9a and 9b show the radiographs of a 28-year-old woman who sustained a head injury and a closed injury, without soft-tissue compromise, to her right lower extremity in a motor vehicle accident. Appropriate management of the foot injury should include

Explanation

DISCUSSION: The displaced talar neck fracture should be treated with open reduction and internal fixation using screws. Closed reduction and casting will not maintain position, and percutaneous pinning is not able to maintain reduction to allow union. External fixation and amputation are not necessary for this injury unless there is severe soft-tissue loss.
REFERENCE: Adelaar RS: Fractures of the talus. Instr Course Lect 1990;39:147-156.

Question 26

A 60-year-old woman has activity-related hip pain after undergoing arthroplasty 5 years ago. She has severe Parkinsonism and denies fevers or chills. Radiographs are shown in Figures 45a and 45b. What is the most likely cause of her pain?

Explanation

DISCUSSION: The radiographs reveal both cement debonding at the lateral shoulder of the prosthesis and a cement mantle fracture. Both of these indicate a loose femoral component. The radiographs show a stress fracture with reactive bone on the lateral femoral cortex in conjunction with the cement mantle fracture. The acetabular component shows no evidence of loosening. Heterotopic bone usually is not a source of pain when it is Brooker grade I, as in this case. Parkinsonism generally is not associated with hip pain.
REFERENCES: Harris WH, McCarthy JC, O’Neill DA: Femoral component loosening using contemporary techniques of femoral cement fixation. J Bone Joint Surg Am 1982;64:1063-1067.
Callaghan JJ, Rosenberg AG, Rubash H (eds): The Adult Hip. Philadelphia, PA, Lippincott-Raven, 1998, pp 960, 1228-1229.
Maloney WJ, Schmalzreid T, Harris WH: Analysis of long-term cemented total hip arthroplasty retrievals. Clin Orthop Relat Res 2002;405:70-78.

Question 27

Figure 100 is the MRI scan of a 52-year-old runner who has right knee pain that has been occurring 10 minutes into her run for 2 months. On examination, she has tenderness over the lateral epicondyle. Her Ober test result is positive. What is the most appropriate initial treatment? Review Topic

Explanation

Iliotibial band syndrome (ITBS) is a common cause of lateral knee pain in runners. Potential etiologies for the pain include repetitive friction, compression, and bursal inflammation. An Ober test is used to assess iliotibial band tightness. With the patient lying on the unaffected side, the affected leg is abducted and extended. The test result is positive if the examiner is unable to adduct the leg from this position. An MRI scan can be helpful in making the diagnosis, but a negative MRI scan does not rule out ITBS. Studies have reported increased signal intensity on T2-weighted images deep to the iliotibial band adjacent to the lateral epicondyle, with thickening of the iliotibial band. Nonsurgical treatment is most appropriate initially and involves activity modification, ice, anti-inflammatory medications, and stretching. Corticosteroid injection to the iliotibial bursa is also an option to treat acute pain. After the initial inflammation improves, a strengthening program is started. Multiple surgical procedures have been described for recalcitrant cases, including iliotibial band excision, Z-lengthening, and iliotibial band bursectomy.

Question 28

Figure 35 shows the radiograph of a 44-year-old woman with rheumatoid arthritis who reports neck pain. Below what threshold number is surgical stabilization warranted for the interval shown by the arrow?

Explanation

DISCUSSION: The posterior atlanto-dens interval represents the space available for the spinal cord and a distance of less than 14 mm is predictive of neurologic progression, thus warranting consideration for fusion, even in the absence of symptoms.
REFERENCE: Boden SD, Dodge LD, Bohlman HH, et al: Rheumatoid arthritis of the cervical spine: A long-term analysis with predictors of paralysis and recovery. J Bone Joint Surg Am 1993;75:1282-1297.

Question 29

What is the most likely cause of recurrent symptoms following excision of a third web space neuroma?

Explanation

DISCUSSION: When a recurrent neuroma forms at the end of the resected nerve, it does not retract far enough because either the transection was not proximal enough or it is tethered by plantar neural branches. The transverse intermetatarsal ligament may reform, but it is not associated with pathology. Synovial cysts and synovitis are part of the differential diagnosis but are not associated with neuroma excision. Complex regional pain syndrome may result from neuroma excision, but this is rare and the symptoms are different.
REFERENCES: Beskin JL: Recurrent interdigital neuromas, in Nunley JA, Pfeffer GB, Sanders RW, Trepman E (eds): Advanced Reconstruction: Foot and Ankle. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2004, pp 481-484.
Amis JA, Siverhus SW, Liwnicz BH: An anatomic basis for recurrence after Morton’s neuroma excision. Foot Ankle 1992;13:153-156.

Question 30

The iliopectineal fascia runs between which of the following structures?

Explanation

DISCUSSION: The sheath of the psoas muscle or the iliopectineal fascia separates the more lateral iliopsoas muscle and the femoral nerve from the more medially located iliac vessels. This fascia has to be taken down to enter the true pelvis.
REFERENCES: Masquelet AC, McCullough CJ, Tubiana R: An Atlas of Surgical Exposures of the Lower Extremity. Philadelphia, PA, JB Lippincott, 1993.
Letournel E, Judet R: Fractures of the Acetabulum, ed 2. Berlin, Germany, Springer Verlag, 1993.
Matta J: Surgical treatment of acetabular fractures, in Browner BD, Jupiter JB, Levine AM, et al (eds): Skeletal Trauma, ed 3. Philadelphia, PA, WB Saunders, 2003, vol 1, pp 1109-1149.

Question 31

What muscle attaches to the site shown by the arrow in Figure 2?

Explanation

DISCUSSION: The latissimus dorsi inserts on the humerus metaphysis between the pectoralis major (posterior) and teres major (anterior). Teres minor inserts on the base of the greater tuberosity. Pectoralis minor does not insert on the humerus.
REFERENCES: Williams PL, Warwick R, Dyson M, Bannister LH: Neurology, in Gray’s Anatomy, ed 37. Edinburgh, Scotland, Churchill Livingstone, 1989, pp 1131-1132.
Last RJ: Anatomy: Regional and Applied, ed 6. London, England, Churchill Livingstone, 1978, pp 131-132.

Question 32

A 55-year-old man underwent cementless total hip arthroplasty for advanced painful osteoarthritis of the hip 2 years ago. The follow-up radiograph shown in Figure 30 shows

Explanation

DISCUSSION: The radiograph shows a well-osseointegrated tapered stem with a metaphyseal porous coating, spot welds in the porous region, and calcar rounding. Trochanteric stress shielding and distal cortical hypertrophy are also signs of ingrown stems but are seen more frequently in association with extensively porous-coated stems exhibiting diaphyseal ingrowth. There is no evidence of lucent lines or a pedestal, signs that suggest instability. Femoral stem subsidence can be determined only by a review of sequential radiographs.
REFERENCES: Engh CA, Massin P, Suthers KE: Roentgenographic assessment of the biologic fixation of porous-surfaced femoral components. Clin Orthop 1990;257:107-128.
Vresilovic E, Hozack WJ, Rothman RH: Radiographic assessment of cementless femoral components: Correlation with intraoperative mechanical stability. J Arthroplasty 1994;9:137-141.

Question 33

At the first postoperative visit after mini-open carpal tunnel release, a patient reports hand weakness. Poor index finger interphalangeal joint extension and metacarpophalangeal joint flexion are present. This finding is most consistent with

Explanation

EXPLANATION:
Complications after carpal tunnel release are relatively uncommon. The clinical picture described above is most consistent with lumbrical muscle weakness secondary to neuropraxia of the proper palmar digital nerve to the index finger supplying motor innervation to that muscle. The recurrent motor branch of the median nerve innervates the thenar musculature and would not present as index finger weakness. A new onset of trigger finger may result from a loss of the pulley effect of the transverse carpal ligament, postoperative tendon inflammation, or previously unrecognized flexor tendon triggering. Flexor digitorum profundus to the index finger lies deep within the carpal tunnel, making its injury unlikely. If it were injured, the result would not be weakness of interphalangeal joint extension.

Question 34

Figures 71a and 71b/ are the MR images of a 65-year-old man who dislocated his shoulder. What is his most likely chief symptom?

Explanation

CLINICAL SITUATION FOR QUESTIONS 72 THROUGH 75
Figures 72a through 72e are the MR images of a 12-year-old boy with left lateral-sided knee pain following a football injury. He has a several-year history of recurrent knee pain that improves with rest. An examination reveals a moderate effusion. Range of motion is 0 degrees
to 90 degrees and is limited by pain in deep flexion. He has tenderness to palpation along the lateral joint line, and no instability is noted.

Question 35

An obese (BMI = 35) 72-year-old woman with diabetes mellitus, hyptertension and a 22-pack-year smoking history is scheduled to undergo posterior spinal fusion from T10 to S1 with a pedicle subtraction osteotomy at L3 for the spinal deformity seen in Figure 1. Which of the following risk factors is most predictive of major complication following surgery Review Topic

Explanation

The patients age (> 60 years) is the most significant risk factor for a major perioperative complication during posterior spinal fusion for adult spinal deformity correction.
The surgical treatment of adult spinal deformity often requires multilevel arthrodesis with complex osteotomies including three column osteotomies such as pedicle
subtraction (PSO) and vertebral column resection (VCR). They can involve both anterior and posterior surgical approaches. Surgical time, blood loss, length of hospital stay, and length of recovery can be greater than it is for the more common degenerative conditions.
Auerbach et al. characterized the risk factors for the development of major complications in patients undergoing 3-column osteotomies for adult spinal deformity correction. They also aimed to determine whether the presence of complications affected the ultimate clinical outcome. They found age > 60 years, > or = 3 comorbid conditions and preoperative sagittal imbalance of = 40mm was associated with a major complication. However, the presence of a major complication did not affect the ultimate clinical outcomes at 2 years or more.
Daubs et al. conducted a retrospective analysis of forty-six patients = 60 years of age who underwent major spinal deformity surgery requiring a minimum 5-level arthrodesis procedure to determine the rate of complication and outcomes. The overall complication rate was 37% and the major complication rate was 20%. Increasing age was a significant factor (p<0.05) in predicting the presence of a complication, while presence of comorbidities was found to have no association.
Figure A is a standing preoperative lateral radiograph of the spine demonstrating a thoracic kyphosis of ~25° and thoracolumbar kyphosis of ~25°. Illustration A demonstrates proper sagittal balance after spinal fusion from T10 to S1 and L3 PSO.
Incorrect Answers:

Question 36

The mother of a 3-month-old infant states that she has difficulty positioning the infant’s legs during diaper changes. Examination reveals limited abduction of both hips and a negative Ortolani sign. A radiograph reveals bilaterally dislocated hips. Initial management consists of guided reduction in a Pavlik harness, with weekly follow-up. Figures 57a and 57b show the radiograph and CT scan obtained after 6 weeks in the harness. Management should now consist of

Explanation

DISCUSSION: In an infant younger than age 6 months with a complete dislocation of the hip that is not initially reducible, the Pavlik harness may be used for a trial of guided reduction. When the harness is used in these patients, the infant should be followed at weekly intervals to see if reduction has been achieved. If the hip does not reduce after 3 to 4 weeks of harness wear, the harness should be discontinued, and closed or open reduction should be considered to avoid secondary deformation of the posterolateral acetabulum, also known as Pavlik harness pathology. Changing to other abduction braces is not indicated.
REFERENCES: Jones GT, Schoenecker PL, Dias LS: Developmental hip dysplasia potentiated by inappropriate use of the Pavlik harness. J Pediatr Orthop 1992;12:722-726.
Atar D, Lehman WB, Grant AD: Pavlik harness pathology. Isr J Med Sci 1991;27:325-330.
Weinstein SL: Developmental hip dysplasia and dislocation, in Morrissy RT, Weinstein SL (eds): Lovell and Winter’s Pediatric Orthopaedics, ed 4. Philadelphia, Pa, Lippincott-Raven, 1996, pp 903-950.

Question 37

Which ligament attaches to the bony fragment identified by the CT image arrows in Figures 42a and 42b?

Explanation

DISCUSSION
The distal tibiofibular syndesmosis is a ligamentous complex that consists of the AITFL, PITFL, intertransverse ligament (ITL), and IOL. The PITFL originates on the posterior inferior aspect of the tibia (Volkmann tubercle) and inserts on the lateral malleolus. The AITFL originates on the anterolateral aspect of the tibia (Chaput tubercle) and inserts on the distal anterior aspect of the fibula (Wagstaffe tubercle). The ITL is a group of fibers running transversely just inferior to the PITFL. As a group, these structures maintain the appropriate tibial plafond and talus relationship throughout physiologic range of motion.
RECOMMENDED READINGS
Carr JB. Malleolar fractures and soft tissue injuries of the ankle. In: Browner BD, Alen LM, Peter TG, Jupiter JB, et al. Skeletal Trauma. 3rd ed. Philadelphia, PA: Saunders; 2003:2309. Zalavras C, Thordarson D. Ankle syndesmotic injury. J Am Acad Orthop Surg.2007 Jun;15(6):330-9. Review. PubMed PMID: 17548882.View Abstract at PubMed
CLINICAL SITUATION FOR QUESTIONS 43 THROUGH 46

A 46-year-old healthy right-hand-dominant man falls and sustains the injury shown in Figures 43a and 43b.

Question 38

Examination of a 25-year-old man who was injured in a motor vehicle accident reveals a fracture-dislocation of C5-6 with a Frankel B spinal cord injury. He also has a closed right femoral shaft fracture and a grade II open ipsilateral midshaft tibial fracture. Assessment of his vital signs reveals a pulse rate of 45/min, a blood pressure of 80/45 mm Hg, and respirations of 25/min. A general surgeon has assessed the abdomen, and a peritoneal lavage is negative. His clinical presentation is most consistent with what type of shock?

Explanation

DISCUSSION: Assessment of the acutely injured patient follows the Advanced Trauma Life Support protocol. Cervical cord injury is often associated with a disruption in sympathetic outflow. Absent sympathetic input to the lower extremities leads to vasodilatation, decreased venous return to the heart, and subsequent hypotension. With hypotension, the physiologic response of tachycardia is not possible because of the unopposed vagal tone. This results in bradycardia. Patient positioning, fluid support, pressor agents, and atropine are used to treat neurogenic shock.
REFERENCE: Sutton DC, Siveri CP, Cotler JM: Initial evaluation and management of the spinal injured patient, in Cotler JM, Simpson JM, An HS, et al (eds): Surgery of Spinal Trauma. Philadelphia, PA, Lippincott Williams & Wilkins, 2000, pp 113-126.

Question 39

An otherwise healthy 76-year-old woman has pain 2 years after total hip arthroplasty. The clinical photograph in Figures below demonstrates her skin envelope, and associated radiograph. Her C-reactive protein level is normal, and her erythrocyte sedimentation rate is mildly elevated. The white blood cell count is normal. Hip aspiration attempted under fluoroscopy generates no fluid. What is the best definitive treatment?

Explanation

DISCUSSION:
This patient clearly has a chronically infected total hip arthroplasty, indicated by the open, draining sinus, as well as trochanteric bone resorption on radiographs, and two years of pain. Recently, specific guidelines have been published to better help the clinician define infection. Repeating the hip aspiration is unnecessary, because infection is already evident. Initiating a wound care consult would not address the underlying infection. The determination whether to retain the components or perform a two-stage exchange is based more on the acuity of infection. In this particular case, the patient is chronically infected. Irrigation and debridement with a liner exchange and retention of the components are reserved for the acute setting.

Question 40

Which of the following plain radiographic views of the shoulder best reveals a Hill-Sachs lesion of the humeral head?

Explanation

Hill-Sachs lesion is an impression fracture of the posterosuperior aspect of the humeral head, produced by contact with the anteroinferior glenoid when dislocated. Hill-Sachs lesion is demonstrated on plain AP radiograph in internal rotation.

Question 41

Figure 48 shows the radiograph of a 17-year-old boy who sustained a gunshot wound to his forearm. There is a small entrance wound on the volar surface. The exit wound is dorsal and more than 15 cm in size, with loss of skin and an extensive amount of devitalized muscle hanging out of the wound. Vascular supply to the hand is excellent, the ulnar and median nerves are intact in the hand, but the radial sensory nerve function is absent. After repeated surgical debridements of the wound and bone, definitive treatment for the fracture would most likely be which of the following? Review Topic

Explanation

The injury needs a very complex traumatic reconstruction. After repeat debridements, there will be a very long segmental loss of the radius, with a significant loss of skin and muscle covering the bone. Spanning external fixation represents a good temporary fixation tool but will not be a definitive solution. The preferred procedure is a vascularized fibular graft with associated skin flap from the lateral leg. This surgical option brings healthy vascularized bone and soft-tissue coverage into an area with significant bone and soft-tissue loss. Placement of large quantities of allograft material, especially strut allograft, is generally contraindicated in the setting of open fractures with soft-tissue compromise because of the risk of infection. Internal fixation and massive cancellous autografting is usually limited to one defect of less than 5 cm with intact soft-tissue covering.

Question 42

Figure 18 shows the radiograph of a patient with a total hip arthroplasty dislocation. During revision, increasing the diameter of the femoral head while maintaining the ratio of head-to-neck diameter constant has the effect of

Explanation

DISCUSSION: Although there is strong clinical and laboratory evidence that suggests smaller head size is linked with lower rates of polyethylene wear, moving to the use of 22-mm heads from larger sizes would tend to increase the dislocation rate. The key premise to this argument is that the absolute size of the femoral neck remains unchanged. While neck diameters were appropriate for the early monoblock femoral components, the use of modular femoral stems allows the surgeon to place 22-mm heads onto the same neck and trunion as used by larger heads. This has the effect of lessening the head-to-neck diameter ratio, which then accentuates the rate of impingement and dislocation. Reducing the neck diameter in proportion to the head diameter would eliminate the range-of-motion penalty accompanying head size reduction.
Scifert and associates used a three-dimensional finite element model to study various combinations of femoral head size and neck ratios. They found that increasing the diameter of the femoral head while maintaining a constant head-to-neck diameter had the effect of significantly increasing the resisting moment necessary to induce a dislocation. The higher the head-to-neck ratio, the greater the range of motion until impingement and the greater the range of motion to dislocation.
REFERENCE: Scifert CF, Brown TD, Pedersen DR, Callaghan JJ: A finite element analysis of factors influencing total hip dislocation. Clin Orthop 1998;355:152-162.

Question 43

A 20-year-old minor league baseball pitcher is diagnosed with a symptomatic torn ulnar collateral ligament (UCL) in his pitching elbow. Nonsurgical management consisting of rest and physical therapy aimed at elbow strengthening has

Explanation

High-level pitchers with symptomatic UCL tears require reconstruction, with autograft being the best studied graft selection. With concomitant ulnar nerve symptoms, a simultaneous ulnar nerve transposition provides good results. Ligament “repairs” and allograft reconstructions have not shown good long-term results.

Question 44

A 14-year-old girl reports a 3-week history of anterior thigh pain and a palpable mass after sustaining a soccer-related injury. Examination reveals a tender, firm mass in the midportion of the rectus femoris. MRI scans are shown in Figures 39a through 39c. What is the most appropriate management? Review Topic

Explanation

The history, examination, and MRI scan findings are consistent with a midsubstance partial rupture of the rectus femoris muscle. This is an injury masquerading as a “pseudo tumor.” The lack of an appreciable mass effect on the T1-weighted MRI scan, the defined fluid signal on the T2-weighted scans, and the lack of significant contrast enhancement after gadolinium are all most consistent with injury rather than a neoplasm. Most of these injuries respond to nonsurgical management; a few will benefit from late debridement and repair if symptoms fail to resolve in 3 to 6 months. The treatment of choice is nonsurgical management with a follow-up MRI scan to verify that the findings are resolving.

Question 45

A 28-year-old professional dancer reports a 3-month history of progressive pain in the posterior aspect of the left ankle. Her symptoms are worse when she assumes the en pointe position. Examination reveals tenderness to palpation at the posterolateral aspect of the ankle posterior to the peroneal tendons which is made worse with passive plantar flexion. There is no nodularity, fluctuance, or tenderness of the Achilles tendon. The neurovascular examination is unremarkable. A lateral radiograph and MRI scan are shown in Figures 16a and 16b, respectively. Management should consist of

Explanation

DISCUSSION: The imaging studies reveal findings typical of the os trigonum syndrome. This condition results from inflammation between the os trigonum and the adjacent talus. The symptoms of posterior ankle pain are exacerbated by plantar flexion, which stresses the fibrous union between these two bones. Definitive management of the high-level athlete involves excision of the os trigonum from a medial approach, although arthroscopic excision has also been described. The os trigonum is not an intra-articular structure; therefore, ankle arthroscopy is neither diagnostic nor therapeutic.
REFERENCES: Abramowitz Y, Wollstein R, Barzilay Y, et al: Outcome of resection of a symptomatic os trigonum. J Bone Joint Surg Am 2003;85:1051-1057.
Mouhsine E, Crevoisier X, Leyvraz P, et al: Post-traumatic overload or acute syndrome of the os trigonum: A possible cause of posterior ankle impingement. Knee Surg Sports Traumatol Arthrosc 2004;12:250-253.
Wredmark T, Carlstedt CA, Bauer H, et al: Os trigonum syndrome: A clinical entity in ballet dancers. Foot Ankle 1991;11:404-406.

Question 46

Figures A through C are the radiograph and CT scans of a 42-year-old man who sustained an injury to both of his ankles and underwent surgical repair 2 weeks prior to presentation to your office. One ankle is healing well. On the contralateral side, he reports pain and restricted ankle range of motion. Management should consist of

Explanation

This patient has a malreduced syndesmosis. The CT scans clearly show the fibula to be subluxated posteriorly relative to the incisura; therefore, surgical revision is warranted. Revision surgery should include either removal of the current screws with accurate reduction of the syndesmosis and new screw placement or repair of the posterior malleolar fragment, which will in turn reduce the syndesmosis. Addition of an anteriorly directed screw to the current construct will not change the malalignment. Loosening the syndesmotic screws or addition of aggressive physiotherapy will not correct the malrotation of the distal fibula within the incisura which is seen on the CT scan. Outcomes after these injuries are related to the reduction of the ankle mortise.

Question 47

The dose of the chemotherapeutic agent doxorubicin (Adriamycin) is limited by which of the following factors?

Explanation

DISCUSSION: Doxorubicin is a chemotherapeutic agent that is best known for dose-limiting cardiotoxicity. This is related not only to the cumulative dose, but also the rate of infusion.
REFERENCE: Brockstein BE, Peabody RD, Simon MA: Soft tissue sarcomas, in Vokes EE, Golomb HM (eds): Oncologic Therapies. Berlin, Springer, 1999, pp 925-952.

Question 48

An obese 10-year-old boy has had left groin pain and a limp for the past 2 months. Examination reveals decreased abduction and internal rotation. Laboratory studies show normal renal function and an elevated thyroid-stimulating hormone (TSH) level. AP and frog lateral radiographs of the pelvis are shown in Figures 30a and 30b. What is the best course of action?

Explanation

DISCUSSION: The radiographs show a grade I slipped capital femoral epiphysis (SCFE) that is classified as stable because the child is able to bear weight. The elevated TSH level indicates possible hypothyroidism. SCFE usually occurs in boys age 12 to 14 years. Because of the patient’s young age and hypothyroidism, he is at increased risk for slippage of the contralateral hip; therefore, prophylactic pinning of the uninvolved side also should be considered. Because of the risk of slip progression, crutch treatment and nonsteroidal anti-inflammatory drugs are not indicated. Realignment osteotomy is not indicated for grade I SCFE. Traction to reduce the slip, followed by pinning, has been advocated for unstable slips but is not indicated here.
REFERENCES: Loder RT, Wittenberg B, DeSilva G: Slipped capital femoral epiphysis associated with endocrine disorders. J Pediatr Orthop 1995;15:349-356.
Wells D, King JD, Roe TF, Kaufman FR: Review of slipped capital femoral epiphysis associated with endocrine disease. J Pediatr Orthop 1993;13:610-614.

Question 49

A 24-year-old man with weakness and atrophy of the thumb for 12 months has very slight numbness on the radial side of his thumb that is constant and not progressing. He has no other hand or finger numbness.His 2-point static sensory examination is unremarkable in all digits and there is marked atrophy of the thenar muscles. His carpal tunnel provocative tests are negative. He has no symptoms on the opposite hand and otherwise is in excellent health. Which next step will most likely reveal the diagnosis?

Explanation

Question 50

A healthy 72-year-old woman is seen 14 days after cemented total knee arthroplasty. She reports increasing pain and swelling for the last 4 days accompanied by 4 days of wound drainage. Examination reveals that she is afebrile, and has erythema and moderate serosanguinous drainage from the wound. The knee is moderately swollen. Aspiration of the knee reveals no organisms on Gram stain. Culture results are expected back in 48 hours. Optimal management should consist of

Explanation

AL-Madena Copy
8 • American Academy of Orthopaedic Surgeons
DISCUSSION: Increased pain, swelling, erythema, and drainage 2 weeks removed from the primary arthroplasty are all signs of a probable infection. Erythrocyte sedimentation rate and C-reactive protein may not be helpful as they are elevated postoperatively even in the absence of infection. Even in the absence of infection, persistent wound drainage is an indication for surgical debridement to prevent subsequent infection. When a postoperative infection is easily recognized by clinical examination, there is no need to wait for a positive culture before proceeding with debridement.
REFERENCES: Weiss AP, Krackow KA: Persistent wound drainage after primary total knee arthroplasty. J Arthroplasty 1993;8:285-289.
Jaberi FM, Parvizi J, Haytmanek CT, et al: Procrastination of wound drainage and malnutrition affect the outcome of joint arthroplasty. Clin Orthop Relat Res 2008;466:1368-1371.
Insall JN, Windsor RE, Scott, WN: Surgery of the Knee, ed 2. New York, NY, Churchill Livingstone, 1993, pp 959-964.

Figure 3a Figure 3b

Question 51

What mechanism of injury is most likely to cause a fracture of the anteromedial facet of the coronoid?

Explanation

Early range of motion
Hinged elbow brace for 4 weeks
Repair lateral collateral ligament
Remove and upsize implant
Remove and downsize implant
The intraoperative images are consistent with overstuffing of the ulnohumeral joint during a radial head replacement. The most appropriate next step would be removing and downsizing the implant.
Overstuffing the radiohumeral joint by >2.5 mm can significantly alter elbow kinematics. It has also shown to lead to pain and early joint disease. The most sensitive method to assess for overstuffing of the joint is by direct visualisation intraoperatively. This can be performed by visualising the lateral aspect of the ulnohumeral joint when the radial head is resected and comparing this to when the trial radial head is reduced in place. In comparison, radiographic asymmetry of the medial ulnohumeral joint has been shown to be less sensitive. Radiographic findings of incongruity of ulnohumeral joint only occurs when significant overlengthening of the radius occurs.
Frank et al. examined the effect of radial head thickness in seven cadaver specimens. They found that incongruity of the medial ulnohumeral joint would only become apparent radiographically after overlengthening of the radius by >or=6 mm.
Doornberg et al. examined seventeen computed tomography scans of the elbow to investigate the height of the radial head relative to the lateral edge and central ridge of the coronoid process. They found that the radial head was on average only 0.9 mm more proximal than the lateral edge of the coronoid process.
Figure A shows intraoperative radiographs of a patient that has undergone a radial head arthroplasty. There is significant widening of the medial ulnohumeral joint on an AP radiograph as well as widening of the ulnohumeral joint on the lateral radiograph,
Incorrect Answers:

Question 52

Figure 29 is the radiograph of a 30-year-old man who sustained an isolated tibial shaft fracture. What is the most common deformity with nonsurgical management?

Explanation

Studies have shown that approximately 25% of diaphyseal fractures of the tibia with intact fibulae will go onto varus malunion if treated nonsurgically. Limb-length
discrepancies are also common. Here the fibula acts as a strut, preventing valgus collapse but predisposing to varus collapse. Valgus and procurvatum is the typical deformity in proximal tibial fractures.

Question 53

Figure 16 shows the radiograph of a 75-year-old man who has progressive groin pain and a limp following total hip replacement. At revision surgery, the anterior and posterior columns of the acetabulum are noted to be intact. The optimal surgical technique for acetabular component reconstruction is a

Explanation

DISCUSSION: Large cementless acetabular components have been shown to perform well in revision acetabular reconstruction. The use of such components is predicated on the presence of adequate anterior and posterior column bone. If a good press-fit can be achieved between the anterior and posterior columns, typically, the remaining defects can be filled with morcellized bone graft. Protrusio cages are typically used in situations where it is not possible to obtain adequate fixation with a large acetabular component. The use of a high hip center with small sockets is more typical of primary arthroplasty in patients with developmental dysplasia of the hip. Bulk acetabular allografts for large segmental defects might be necessary in certain situations, although the use of bulk allografts has resulted in a high failure rate after 5 years. Early results of the use of protrusio cages and bone grafting for large segmental defects have been favorable.
REFERENCES: Petrera P, Rubash HE: Revision total hip arthroplasty: The acetabular component. J Am Acad Orthop Surg 1995;3:15-21.
Lachiewicz PF, Poon ED: Revision of a total hip arthroplasty with a Harris-Galante porous-coated acetabular component inserted without cement: A follow-up note on the results at five to twelve years. J Bone Joint Surg Am 1998;80:980-984.

Question 54

Which of the following imaging modalities is most accurate in locating a toothpick in the plantar arch of the foot?

Explanation

DISCUSSION: Ultrasound is best at imaging abrupt changes in the density of adjacent tissue and therefore is best at imaging wood in the soft tissues of the foot.
REFERENCES: Mizel MS, Steinmetz ND, Trepman E: Detection of wooden foreign bodies in muscle tissue: Experimental comparison of computed tomography, magnetic resonance imaging, and ultrasonography. Foot Ankle Int 1994;15:437-443.
Jacobson JA, Powell A, Craig JG, et al: Wooden foreign bodies in soft tissue: Detection at US. Radiology 1998;206:45-48.

Question 55

What arterial vessel is most prone to injury during posterior iliac crest bone graft harvest?

Explanation

DISCUSSION: The superior gluteal artery is most at risk with a posterior iliac crest bone graft harvest. The artery leaves the pelvis through the sciatic notch and can be injured by retractors or other sharp instruments entering the sciatic notch area. The deep circumflex iliac, iliolumbar, and fourth lumbar arteries supply the iliacus and iliopsoas muscles and can be damaged during anterior bone graft harvest. The ascending branch of the lateral femoral circumflex artery is at risk during the anterior approach to the hip.
REFERENCES: Guyer RD, Delmarter RB, Fulp T, Small SD: Complications of cervical spine surgery, in Herkowitz HN, Garfin SR, Balderston RA, Eismont FJ, Bell GR, Wiesel SW (eds): Rothman-Simeone The Spine, ed 4. Philadelphia, PA, WB Saunders, 1999, p 547.
Kurz LT, Garfin SR, Booth RE Jr: Iliac bone grafting: Techniques and complications of harvesting, in Garfin SR (ed): Complications of Spine Surgery. Baltimore, MD, Williams and Wilkins, 1989, pp 330-331.
Hoppenfeld S, deBoer P: Surgical Exposures in Orthopaedics: The Anatomic Approach. Philadelphia, PA, JB Lippincott, 1984, pp 297, 331-332.

Question 56

Figures 9a through 9c are the preoperative radiographs and a T2-weighted MR image of a patient treated with surgery for spondylolisthesis and neuroforaminal stenosis. Figure 9d is the postsurgical radiograph. Interbody fusion offers which advantage over posterolateral fusion (PLF)? A B C D

Explanation

DISCUSSION
Interbody fusion, when compared to PLF, is a predictor of more substantial blood loss. Multilevel posterior lumbar interbody fusion (PLIF) is an independent predictor of blood loss for posterior spine fusion. Some retrospective studies suggest that fusion rates are higher for transforaminal lumbar interbody fusion (TLIF) than PLF, but this finding has not been borne out in prospective studies. The main advantage of TLIF in the context of this question is restoration of neuroforaminal height, and many surgeons will consider TLIF or PLIF for that reason. The parasagittal MR image seen in Figure 9c shows neuroforaminal narrowing. The pre- and postsurgical radiographs show a difference in neuroforaminal height.
RECOMMENDED READINGS
DiPaola CP, Molinari RW. Posterior lumbar interbody fusion. J Am Acad Orthop Surg. 2008 Mar;16(3):130-9. Review. PubMed PMID: 18316711. View Abstract at PubMed
Eismont FJ, Norton RP, Hirsch BP. Surgical management of lumbar degenerative spondylolisthesis. J Am Acad Orthop Surg. 2014 Apr;22(4):203-13. doi: 10.5435/JAAOS-22-04-203. Review. PubMed PMID: 24668350. View Abstract at PubMed
McAfee PC, DeVine JG, Chaput CD, Prybis BG, Fedder IL, Cunningham BW, Farrell DJ, Hess SJ, Vigna FE. The indications for interbody fusion cages in the treatment of spondylolisthesis: analysis of 120 cases. Spine (Phila Pa 1976). 2005 Mar 15;30(6 Suppl):S60-5. PubMed PMID: 15767888. View Abstract at PubMed
RESPONSES FOR QUESTIONS 10 THROUGH 14
Postoperative deep surgical site infection
Proximal junctional kyphosis
Pedicle screw cut-out
Pseudarthrosis
Sagittal imbalance
Please match the scenario described below with the most likely complication listed above.

Question 57

A 30-year-old man who underwent an anterior lumbar diskectomy and fusion at L4-5 and L5-S1 through an anterior retroperitoneal approach 1 month ago now reports he is unable to obtain and maintain an erection. The most likely cause of this condition is

Explanation

DISCUSSION: Sexual dysfunction is a common condition after extensive anterior lumbar surgical dissection. Erectile dysfunction usually is nonorganic but may be related to parasympathetic injury. The parasympathetic nerves are deep in the pelvis at the level of S2-3 and S3-4 and usually are not involved in the surgical field for anterior L4-5 and L5-S1 procedures. Retrograde ejaculation is the result of injury to the sympathetic chain on the anterior surface of the major vessels crossing the L4-5 level and at the L5-S1 interspace. Erectile function and orgasm are not affected by sympathetic injury. The pudendal nerve is primarily a somatic nerve and is not located in the surgical field.
REFERENCES: Flynn JC, Price CT: Sexual complications of anterior fusion of the lumbar spine. Spine 1984;9:489-492.
Johnson RM, McGuire EJ: Urogenital complications of anterior approaches to the lumbar spine. Clin Orthop 1981;154:114-118.

Question 58

A college football player performs bicep curls as part of his weight lifting routine. During the flexion phase of the curl, what term defines the type of muscle contraction?

Explanation

DISCUSSION: Muscle contractions can be classified by tension, length, and velocity. Isometric contractions involve changing tension in the muscle while the muscle stays at a constant length. An example would be pushing against a wall. Isokinetic contractions occur when the muscle maximally contracts at a constant velocity. Isotonic contractions involve constant tension throughout the range of motion. Eccentric contraction is when the muscle lengthens during contraction. Eccentric contractions have the highest risk of injury. Plyometrics are eccentric contractions at a rapid rate.
REFERENCES: Simon SR (ed): Orthopaedic Basic Science. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1994, pp 89-125.
Evans WJ: Effects of exercise on senescent muscle. Clin Orthop 2002;403:S211-S220.

Question 59

A 16-year-old football player sustains a direct blow to the anterior aspect of his flexed right knee. Examination reveals a contusion over the anterior tibial tubercle and a small effusion. MRI scans are shown in Figures 33a through 33c. What is the most likely diagnosis?

Explanation

DISCUSSION: The MRI scans show disruption of the fibers of the PCL. Patients sustaining an isolated acute PCL injury can present with only minimal discomfort and have full range of motion. When examination reveals a contusion over the tibial tubercle and discomfort with the posterior drawer examination, with or without instability, a possible injury to the PCL should be considered. In acute injuries, the reported accuracy of MRI imaging for diagnosing PCL tears ranges from 96% to 100%.
REFERENCES: Resnick D, Kang HS: Internal Derangement of Joints: Emphasis on MRI Imaging. Philadelphia, PA, WB Saunders, 1997, pp 699-700.
Harner CD, Hoher J: Evaluation and treatment of posterior cruciate ligament injuries. Am J Sports Med 1998;26:471-482.
Fischer SP, Fox JM, Del Pizzo W, Friedman MJ, Snyder SJ, Ferkel RD: Accuracy of diagnoses from magnetic imaging of the knee: A multi-center analysis of one thousand and fourteen patients. J Bone Joint Surg Am 1991;73:2-10.

Question 60

Which of the following conditions routinely requires early surgical intervention in patients with Marfan syndrome? Review Topic

Explanation

Marfan syndrome is a challenging disease for the orthopaedic surgeon. Most problems of joint laxity, acetabular protrusio, and minor scoliosis curves are treated nonsurgically. Pseudarthrosis of the tibia is not seen in Marfan syndrome; it is more common in patients with neurofibromatosis (NF-1). Treating kyphosis is risky for vertebral subluxation. Rapidly progressive scoliosis in immature patients is associated with higher surgical complications, but surgery is indicated. Overcorrection is associated with significant cardiovascular complications and should be avoided.

Question 61

Kinematic testing of patellofemoral motion demonstrates that malalignment that produces increased Q angle causes a shift of the patella laterally in the trochlear groove and is most pronounced during what phase of the flexion arc? Review Topic

Explanation

Dynamic patellofemoral joint contact measurements on cadaveric knees with simulated increased Q angle demonstrated that forces shifted to the lateral facet. The lateral shift in the patella was most pronounced from 40 to 90 degrees of flexion. At lower degrees of flexion, the lateral shift was significantly less. At higher degrees of flexion, the continued shift of the patella was not as pronounced.

Question 62

Figure 27 shows the radiograph of a 68-year-old woman with a history of rheumatoid arthritis who was injured in a fall. History reveals that she has been asymptomatic since undergoing a left total knee arthroplasty 9 years ago. Management should consist of

Explanation

DISCUSSION: A supracondylar fracture of the femur that occurs after total knee replacement can be treated effectively by a number of methods. For this fracture, the use of a retrograde supracondylar nail has been found to be effective in several series. The treatment of these complex injuries needs to be individualized based on the stability of the implant, the quality of the bone, and the extent of comminution of the fracture. Revision with the use of an unstemmed implant will not result in effective stabilization of the knee or the fracture.
REFERENCE: Ayers DC: Supracondylar fracture of the distal femur proximal to a total knee replacement, in Springfield DS (ed): Instructional Course Lectures 46. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1997, pp 197-203.

Question 63

A collegiate golfer sustains a hook of the hamate fracture. After 12 weeks of splinting and therapy, the hand is still symptomatic. What is the most appropriate management to allow return to competitive activity?

Explanation

DISCUSSION: Excision of the fracture fragment typically leads to rapid return to function. Fixation techniques are difficult to perform because of the size of the bone; hardware prominence is common. Nerve deficits are not typically noted in this injury. The motor branch of the ulnar nerve in Guyon’s canal must be protected during the surgical approach.
REFERENCES: Kulund DN, McCue FC III, Rockwell DA, et al: Tennis injuries: Prevention and treatment: A review. Am J Sports Med 1979;7:249-253.
Morgan WJ, Slowman LS: Acute hand and wrist injuries in athletes: Evaluation and management. J Am Acad Orthop Surg 2001;9:389-400.

Question 64

Which of the following best describes the course of the median nerve at the elbow?

Explanation

DISCUSSION: The median nerve courses superficial to the ulnar artery, deep to the fibrous arch of the superficialis muscle, and deep to the superficial head of the pronator teres muscle. The median nerve lies within the interval between the flexor digitorum superficialis muscle and the flexor digitorium muscle as it progresses toward the wrist.
REFERENCES: Hoppenfeld S, deBoer P: Surgical Exposures in Orthopaedics, ed 2. Philadelphia, PA, Lippincott-Raven, 1994, pp 118-131.
Netter F: The Ciba Collection of Medical Illustrations: The Musculoskeletal System. Part 1, Anatomy, Physiology and Metabolic Disorders. West Caldwell, NJ, Ciba-Geigy, 1991, vol 8,

pp 46-47.

Question 65

Examination of a 4-year old child with obstetrical palsy reveals weak deltoids, pectoralis major strength of 4-5, and normal hand function. External rotation of the shoulder is limited. What is the most appropriate surgical procedure to restore external rotation?

Explanation

DISCUSSION: Transfer of the latissimus dorsi and teres major to the posterior rotator cuff will restore external rotation and some abduction. The procedure should be performed in children who are approximately age 4 years, following spontaneous recovery and prior to significant stiffness. External rotation osteotomy is more appropriate for an older child. Fusion should not be performed until skeletal maturity. Distal biceps rerouting restores pronation for a supination deformity. Latissimus dorsi and teres major transfer to the subscapularis would accentuate the internal rotation. In younger patients without significant bony deformity, a subscapularis slide or lengthening can restore external rotation.
REFERENCES: Strecker WB, McAllister JW, Manske PR, Schoenecker PL, Dailey LA: Sever-L’Episcopo transfers in obstetrical palsy: A retrospective review of twenty cases. J Pediatr Orthop 1990;10:442-444.
Hoffer MM, Wickenden R, Roper S: Brachial plexus birth palsies. J Bone Joint Surgery Am 1978;60:692-695.

Question 66

What is the advantage of percutaneous pedicle screw fixation over open instrumentation and fusion for a thoracolumbar burst fracture without neurologic deficit?

Explanation

DISCUSSION
A prospective randomized study on short-segment treatment of burst fractures with and without fusion demonstrated similar outcomes at 5 years with lower blood loss in the nonfusion group. There is by definition no fusion performed with percutaneous stabilization, so patients often develop hardware failure. Some surgeons routinely remove instrumentation following percutaneous stabilization, thus revision surgery is common. Clinical outcomes are not improved compared to open methods.
RECOMMENDED READINGS
Koreckij T, Park DK, Fischgrund J. Minimally invasive spine surgery in the treatment of thoracolumbar and lumbar spine trauma. Neurosurg Focus. 2014;37(1):E11. doi: 10.3171/2014.5.FOCUS1494. Review. PubMed PMID: 24981899. View Abstract at PubMed Jindal N, Sankhala SS, Bachhal V. The role of fusion in the management of burst fractures of the thoracolumbar spine treated by short segment pedicle screw fixation: a prospective randomised trial. J Bone Joint Surg Br. 2012 Aug;94(8):1101-6. doi: 10.1302/0301-620X.94B8.28311. PubMed PMID: 22844053. View Abstract at PubMed
Dai LY, Jiang LS, Jiang SD. Posterior short-segment fixation with or without fusion for thoracolumbar burst fractures. a five to seven-year prospective randomized study. J Bone
Joint Surg Am. 2009 May;91(5):1033-41. doi: 10.2106/JBJS.H.00510. PubMed PMID:

Question 67

Which of the following nerves is most commonly injured when obtaining a bone graft from the posterior ilium?

Explanation

DISCUSSION: Cutaneous sensation to the buttock is provided by the superior, middle, and inferior cluneal nerves. The superior cluneal nerves are the lateral branches of the dorsal rami of the upper three lumbar nerves and penetrate deep fascia just proximal to the iliac crest. They pass distally to the skin of the buttock and will be injured if the exposure extends more than 8 cm anterolateral to the posterior superior iliac spine. The lateral femoral cutaneous nerve can be injured in an anterior ilium bone graft. The superior gluteal nerve or even the sciatic nerve can be injured if bone is removed from the sciatic notch or dissection is not kept subperiosteal; however, the rate of injury is far less than cluneal nerve injury. The L5 and S1 nerve roots are anterior and can be injured if the inner table bone is harvested and the dissection is not kept subperiosteal or is too medial; however, the rate of injury still is far less than cluneal nerve injury.
REFERENCES: Hoppenfeld S, deBoer P: Surgical Exposures in Orthopaedics: The Anatomic Approach. Philadelphia, PA, JB Lippincott, 1984, pp 295-297.
Hollinshead WH: Textbook of Anatomy, ed 3. Hagerstown, MD, Harper and Row, 1974, p 379.
Last RJ: Anatomy: Regional and Applied, ed 6. London, England, Churchill Livingstone, 1978, p 23.
Ebraheim NA, Elgafy H, Xu R: Bone-graft harvesting from iliac and fibular donor sites: Techniques and complications. J Am Acad Orthop Surg 2001;9:210-218.

Question 68

A 45-year-old male falls off his motorcycle and injures his arm. AP and lateral radiographs reveal an ulnar shaft fracture, 30 degrees apex anterior, and a radial head dislocation. Which direction is the radial head most likely dislocated?

Explanation

DISCUSSION: A monteggia fracture with apex anterior ulnar shaft fracture is associated with an anterior radial head dislocation (See Illustration A). Bado initially described and classified these injuries. The most common injury pattern is an extension type 1 with anterior radial head dislocation and apex anterior ulnar shaft fracture. The apex of the ulna fracture determines the direction of the radial head subluxation or dislocation. Adults typically require ORIF of the ulna. These fractures in children are often treated non-operatively with closed reduction if the ulna fracture is transverse and stable as illustrated by Fowles' case series, but may also require pinning if the fracture is oblique and unstable.

Question 69

What are the optimal conditions for leaving the acetabular shell in place, replacing the acetabular liner, and grafting the osteolytic defect shown in Figure 39?

Explanation

DISCUSSION: Dense pods of ingrowth into the porous coating of cementless ingrowth sockets are seen. Channels through the non-ingrown portion allow access to the trabecular bone of the ilium. Polyethylene wear debris can enter these areas through screw holes. Expansile, lytic lesions can result, which can become large without compromising implant fixation. Loosening is late and results from catastrophic loss of bone. A well-fixed acetabular component with a modular design, a well-designed locking mechanism, and a good survivorship history is a candidate for exchange of the liner and grafting of the osteolytic lesion.
REFERENCES: Ries MD: Complications in primary total hip arthroplasty: Avoidance and management. Wear. Instr Course Lect 2003;52:257-265.
Dumbleton JH, Manley MT, Edidin AA: A literature review of the association between wear rate and osteolysis in total hip arthroplasty. J Arthroplasty 2002;17:649-661.
Pelicci PM, Tria AJ Jr, Garvin KL (eds): Orthopaedic Knowledge Update: Hip and Knee Reconstruction 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2000,
pp 175-180.

Question 70

What is the treatment of choice for an adult who has an isolated fracture of the ulna at the junction of the distal and middle thirds, with 5 degrees apex dorsal angulation and 25% displacement?

Explanation

This is the correct answer for various reasons, based on the question. Key points isolated fracture, distal and middle thirds, and only 25% displace. The author is implying minimal displacement. According to Gebuhr, Holmich a fracture such as describe in the question which does not require close reduction and only initial mobilization are better satisfied with a functional brace. Their study revealed that elbow extension/flexion and forearm pronation/supination had no difference with long arm cast, but wrist extension/flexion greatly improved with the functional bracing. Selections (1) more indicated for midshaft (3) is not inappropriate, but the authors felt it was not necessary because there was greater patient satisfaction with functional bracing and same results except wrist motion was better. (4), (5) are indicated for greater severity of fracture and failed union.

Question 71

Figures 28a through 28d show the radiographs and MRI scans of a 20-year-old basketball player who sustained an inversion injury to his right ankle. Management should consist of

Explanation

DISCUSSION: Osteochondral fractures involving the talar dome have been classified based on radiographic and MRI findings. A nondisplaced and incomplete fracture may be treated effectively with a short leg cast and no weight bearing for 6 weeks. This patient has a complete, separated, and displaced osteochondral fragment involving the midlateral talar dome that will most likely cause pain, mechanical symptoms, and effusion if treated nonsurgically. In addition, there is very little bone remaining on the fragment, making the likelihood of healing with open reduction and internal fixation problematic. The treatment of choice includes arthroscopy, removal of the loose fragment, curettage or drilling of the base, and a rehabilitation program that emphasizes peroneal strengthening, range of motion, and proprioceptive training.
REFERENCES: Lutter LD, Mizel MS, Pfeffer GB (eds): Orthopaedic Knowledge Update: Foot and Ankle. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1994, pp 205-226.
Baker CL, Morales RW: Arthroscopic treatment of tranchondral talar dome fractures: A long-term follow-up study. Arthroscopy 1999;15:197-202.

Question 72

After stabilizing a bimalleolar ankle fracture with a plate and lag screws for the fibula and two interfragmental compression screws for the medial malleolus, a syndesmosis screw is indicated in which of the following situations?

Explanation

DISCUSSION: It is imperative to recognize the need for a position screw (syndesmosis screw) to hold the syndesmosis in proper alignment when surgically stabilizing an ankle fracture. Although many different fracture patterns are suspicious for a disrupted syndesmosis, the only sure way to assess the syndesmosis is to stress it with abduction and external rotation of the talus and attempt to displace the fibula from the incisura fibularis. Under fluoroscopy, the talus will move laterally and displace the fibula, show a valgus talar tilt, or show an increase in the medial clear space. If any or all of these signs occur, a syndesmosis screw is inserted after making sure that the fibula is reduced into the incisura fibularis. This screw may traverse three or four cortices but must not act as a lag screw. It usually is inserted with the ankle in maximal dorsiflexion, although this is probably not necessary because it is almost impossible to overcompress the syndesmosis. The diameter of the screw does not make any difference. It may or may not be removed but not before 3 months.
REFERENCES: Tornetta P III, Spoo JE, Reynolds FA, Lee C: Overtightening of the ankle syndesmosis: Is it really possible? J Bone Joint Surg Am 2001;83:489-492.
Stover MD, Kellam JF: Articular fractures: Principles, in Ruedi TP, Murphy WM (eds): AO Principles of Fracture Management. Stuttgart, Thieme, 2000, pp 105-119.
Hahn DM, Colton CL: Malleolar fractures, in Ruedi TP, Murphy WM (eds): AO Principles of Fracture Management. Stuttgart, Thieme, 2000, pp 559-581.
Tile M: Fractures of the ankle, in Schatzker J, Tile M (eds): Rationale of Operative Fracture Care, ed 2. Berlin, Springer-Verlag, 1998, pp 523-561.

Question 73

The injection shown in Figures 1a and 1b would most benefit a patient who reports which of the following symptoms?

Explanation

DISCUSSION: The images demonstrate a L5 selective root block as it exits the L5-S1 foramen. This root block best helps relieve pain or paresthesias in the L5 distribution, which is the dorsal first web space and the great toe. The lateral foot is an S1 distribution and would need to be blocked through the posterior first sacral foramen. The anterior shin and thigh represent the

L4 root which exits a level above this at the L4-5 foramen. A stocking distribution is nonanatomic and not indicative of a specific root.
REFERENCES: Magee D: Principles and concepts, in Orthopaedic Physical Assessment, ed 3. Philadelphia, PA, WB Saunders, 1997, pp 1-18.
Aeschbach A, Mekhail NA: Common nerve blocks in chronic pain management. Anesthesiol Clin North Am 2000;18:429-459.

Question 74

What is the most appropriate treatment?

Explanation

DISCUSSION
A common postsurgical problem after TKA is a sudden increase of pain that typically occurs about 2 to 3 weeks after surgery. ESR findings are not reliable during the acute postsurgical period. A CRP level exceeding 100 mg/L during the acute postsurgical period is a joint aspiration indication. If the patient does not have sepsis, there is no emergency. This pain is likely attributable to too much activity during physical therapy. Observation is recommended for this patient.

Question 75

A 65-year-old man has a painful mass of the middle finger. A clinical photograph, lateral radiograph, coronal MRI scan, and biopsy specimen are seen in Figures 20a through 20d. What is the most likely diagnosis?

Explanation

DISCUSSION: Although the degeneration of an isolated benign cartilaginous lesion into a chondrosarcoma is rare, it occurs in roughly 10% of patients with Ollier’s disease. Pain is the most common symptom of chondrosarcoma. The treatment of low-grade chondrosarcoma ranges from intralesional excision to wide amputation. The intent of the surgery is to remove all the disease to decrease the chance of local recurrence.
REFERENCES: Lee FY, Mankin HJ, Fondren G, et al: Chondrosarcoma of bone: An assessment of outcome. J Bone Joint Surg Am 1999;81:326-338.
Kasser JR (ed): Orthopaedic Knowledge Update 5. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1996, pp 181-193.

Question 76

Figures below show the radiographs obtained from a 68-year old man with progressively worsening right side hip pain over the last 8 months. He is 6 feet tall, with a BMI of 51 kg/m 2 and reports that his index total hip arthroplasty was performed 8 years ago. The preoperative work-up includes negative infectious laboratory results. What is the most appropriate surgical plan for revision of the femoral component in this patient?

Explanation

DISCUSSION:
The patient’s radiographs demonstrate varus femoral remodeling around a broken cylindrical, distally fixed femoral stem. Proximal femoral remodeling around loose or fractured stems occurs in 21% to 42% of femoral revisions, based on the definitions outlined by Foran and associates. In definition 1, varus femoral remodeling occurs when the template falls within 2 mm of the endosteal cortex of the metaphysis on templating with a diaphyseal engaging stem. In definition 2, varus femoral remodeling = when the template crosses the lateral femoral cortex proximally. Based on the templating or drawing a line from the isthmus proximally along the lateral cortex, implantation of a straight stem would perforate the cortex proximally, indicating varus femoral remodeling. An extended trochanteric osteotomy would aid in the removal of the well-fixed distal segment and enable the safe insertion of the new femoral component. The approach is not the concern in this case, because extended trochanteric osteotomies have been described from the posterior and direct lateral approaches with excellent outcomes and union rates. The key is that the extended osteotomy is necessary and not a trochanteric slide or standard (shorter or incomplete trochanteric) osteotomy. These types would not provide access to the well-fixed distal stem, nor would they afford a straight tube in which to insert a new femoral component.

Question 77

An otherwise healthy year-old woman has pain 2 years after total hip arthroplasty. The clinical photograph in below demonstrates her skin envelope, and associated radiograph. Her C-reactive protein level is normal, and her erythrocyte sedimentation rate is mildly elevated. The white blood cell count is normal. Hip aspiration attempted under fluoroscopy generates no fluid. What is the best definitive treatment?

Explanation

Question 78

A 12-year-old boy with a family history of neurofibromatosis has anterolateral bowing of the left tibia. He has no pain and is ambulatory. Radiographs show a narrowed medullary canal but intact cortices. Treatment should consist of which of the following?

Explanation

DISCUSSION: Anterolateral bowing of the tibia is associated with confirmed neurofibromatosis in approximately 50% of patients. Although the risk of fracture with the development of pseudarthrosis exists, the initial treatment consists of bracing through maturity.
REFERENCES: Vander Have KL, Hensinger RN, Caird M, et al: Congenital pseudarthrosis of the tibia.
J Am Acad Orthop Surg 2008;16:228-236.
Vitale MG, Guha A, Skaggs DL: Orthopaedic manifestations of neurofibromatosis in children: An update. Clin Orthop Relat Res 2002;401:107-118.

Question 79

In patients with Crowe types III and IV developmental dysplasia of the hip with high hip centers, acetabular reconstruction often requires lowering the acetabular component into the native acetabulum. In doing so, considerable risk for limb lengthening beyond 4 cm exists, making the hip difficult to reduce and raising the risk for nerve injury. Which technique is used to overcome this problem?

Explanation

DISCUSSION:
When substantial lengthening of a dysplastic hip will occur because a high dislocation is relocated into a considerably lower acetabulum, a femoral shortening may be necessary to reduce the hip and avoid a stretch injury to the sciatic nerve. No other choice specifically addresses the need for femoral shortening, and high offset stems and lateralized liners may exacerbate the problem if used alone and without femoral shortening.

Question 80

In infantile idiopathic scoliosis, which of the following factors suggests progression?

Explanation

DISCUSSION: Infantile idiopathic scoliosis occurs more commonly in boys, with a 3 to 1 male to female ratio. Neural axis abnormalities, hip dysplasia, and congenital heart disease are all associated with the condition; spontaneous correction frequently occurs. Curve progression can be predicted by the rib vertebral angle difference or the phase of the rib head. Rib overlap of the apical vertebral body or a rib vertebral angle difference of greater than 20 degrees indicates that the curve is likely to progress. Gender, family history, and age at presentation have not been found to be risk factors for progression.
REFERENCES: Mehta MH: The rib-vertebra angle in the early diagnosis between resolving and progressive infantile scoliosis. J Bone Joint Surg Br 1972;54:230-243.
Fischgrund JS (ed): Orthopedic Knowledge Update 9. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2008, p 697.

Question 81

A 72-year-old woman who is right hand-dominant has severe pain in the right shoulder that has failed to respond to nonsurgical management. She reports night pain and significant disability. Examination reveals 30 degrees of active forward elevation. An AP radiograph is shown in Figure 27. Which of the following treatment options will provide the best functional improvement?

Explanation

DISCUSSION: The patient has end-stage rotator cuff tear arthropathy. The radiograph shows complete proximal humeral migration (acromiohumeral interval of 0 mm), severe glenohumeral arthritis, and acetabularization of the acromion. In addition, she has "pseudoparalysis" with active elevation of only 30 degrees. Reverse shoulder arthroplasty affords her the best opportunity for pain relief and functional improvement. The other procedures have mixed results but typically are better for pain relief than they are for functional gains.
REFERENCES: Frankle M, Siegal S, Pupello D, et al: The reverse shoulder prosthesis for glenohumeral arthritis associated with severe rotator cuff deficiency: A minimum two-year follow-up study of sixty patients. J Bone Joint Surg Am 2005;87:1697-1705.
Werner CM, Steinmann PA, Gilbart M, et al: Treatment of painful pseudoparesis due to irreparable rotator cuff dysfunction with the Delta III reverse-ball-and-socket total shoulder prosthesis. J Bone Joint Surg Am 2005;87:1476-1486.

Question 82

Figure 1 is the radiograph of an otherwise healthy 68-year-old man with a 4-year history of increasing global left knee pain. He has noticed stiffness, and despite physical therapy, bracing and nonsteroidal anti-inflammatory drugs, he has continued to develop worsening symptoms and progression in his deformity. Physical examination demonstrates 80°of flexion and a 10° flexion contracture. What is the best next step?

Explanation

Figures 1 and 2 are the radiographs of a 70-year-old man who underwent knee explantation with antibiotic spacer placement. At the time of second- stage surgery for reimplantation of a total knee arthroplasty, a medial parapatellar arthrotomy is used to access the knee. An extensive synovectomy is performed and the gutters are recreated. Medial and lateral joint line releases are done, and scar tissue is removed from around the patella. The cement spacer is removed and the nail is cut and extracted. However, despite this, the knee only flexes 45° and lateral exposure is compromised. What is the best next step?

Question 83

Figures 169a through 169c show the radiograph and MRI scans of a 74-year-old woman who has had back and bilateral leg pain for the past 6 months. Nonsurgical management has failed to provide relief. What is the best option for surgical treatment? Review Topic

Explanation

The patient has symptoms of lumbar spinal stenosis and radiographic evidence of a grade I degenerative spondylolisthesis at L4-5. Surgical treatment has been shown to provide better clinical outcomes than nonsurgical management. Treatment for spondylolisthesis remains somewhat controversial but posterior lumbar instrumented arthrodesis is best supported in the literature. Decompression alone places the patient at risk for recurrent stenosis and progression of deformity. Noninstrumented arthrodesis for this condition results in high rates of nonunion and worsened longterm outcomes. There is insufficient evidence to support the role for interbody arthrodesis (either through an anterior or posterior approach) compared with posterior decompression and arthrodesis.

Question 84

Two weeks after undergoing total knee arthroplasty, a 68-year-old woman experiences moderate, yet worsening, knee pain. Upon examination, she can walk with a cane but she has swelling with mild reactive erythema. She has a well-healed incision with no drainage. A review of her medications reveals the she has been taking warfarin and has an international normalized ratio (INR) of 4.0. Her erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) level are slightly elevated, and radiographs are unremarkable other than for effusion. What is the most likely diagnosis?

Explanation

DISCUSSION
This patient likely has a hemarthrosis related to INR elevation. The slight elevations in ESR and CRP are likely attributable to the nature of the surgery itself rather than an infection, and the mild reactive erythema is likely attributable to the hemarthrosis.

Question 85

What is the most likely contributory factor to this patient's problem?

Explanation

DISCUSSION
Proximal humeral epiphysiolysis (little leaguer’s shoulder) is an overuse condition of the proximal humeral physis. Patients report diffuse pain that is worse with throwing. Little leaguer’s shoulder is caused by rotational stress placed on the proximal humeral epiphysis during overhead throwing. The growth plate is weakest to torsion stress and is most susceptible to injury during periods of rapid growth commonly seen during puberty. Most chronic shoulder injuries occur in throwing athletes between 13 and 16 years of age. Factors that contribute to the condition include excessive throwing, improper throwing mechanics, and muscle-tendon imbalance. Radiographic findings typically are normal but may indicate subtle widening of the proximal humeral physis, and, in more severe cases, metaphyseal demineralization or fragmentation. Surgical fixation is not required for healing. An initial 3-month period of rest and activity modification will typically result in resolution of symptoms. Nonsteroidal anti-inflammatory drugs may be used as needed. After the rest period, a gradual return to throwing is implemented until the patient’s condition returns to baseline. This protocol has a long-term success rate exceeding 90%. Pitching coaches should evaluate throwing mechanics and maintain pitch counts. The most common cause of this condition is overuse, as is seen in pitchers who throw all year. Internal rotation deficit and internal impingement is typically a finding in older athletes without open physes. This patient had no evidence of rotation deficit upon examination, making this diagnosis unlikely.

Question 86

A nonambulatory verbal 6-year-old child with spastic quadriplegic cerebral palsy has progressive bilateral hip subluxation of more than 50%. There is no pain with range of motion, but abduction is limited to 20 degrees maximum. An AP radiograph is seen in Figure 34. Management should consist of

Explanation

DISCUSSION: The natural history of the patient’s hips, if left untreated, is gradual progression to dislocation. To prevent future pain, prevention of dislocation is often helpful. The patient is too old for soft-tissue releases alone. Therefore, the treatment of choice is medial release of both hips to obtain 45 degrees or better of hip abduction in conjunction with psoas tenotomy and bilateral femoral varus osteotomies.
REFERENCES: Presedo A, Oh CW, Dabney KY, et al: Soft-tissue releases to treat spastic hip subluxation in children with cerebral palsy. J Bone Joint Surg Am 2005;87:832-841.
Miller F, Bagg MR: Age and migration percentage as risk factors for progression in spastic hip disease. Dev Med Child Neurol 1995;37:449-455.

Question 87

A 26-year-old right hand-dominant man has had right shoulder pain for the past 6 months. History reveals that he was the starting pitcher for his high school team. Activity modification, physical therapy, cortisone injection, and anti-inflammatory drugs have failed to improve his symptoms. He has a positive O’Brien’s active compression test. What is the next most appropriate step in the diagnosis of this patient? Review Topic

Explanation

MRI-arthrography has been shown to be an accurate technique for assessing the glenoid labrum in patients with suspected labral tears. Often standard MRI technique will not identify labral lesions. The use of MRI-arthrography with an intra-articular injection of gadolinium provides improved visualization of labral lesions. Bencardino and associates demonstrated a sensitivity of 89%, a specificity of 91%, and an accuracy of 90% in detecting labral lesions. SLAP lesions can be visualized on coronal oblique sequences as a deep cleft between the superior labrum and the glenoid that extends well around and below the biceps anchor. Often, contrast will diffuse into the labral fragment, causing it to appear ragged or indistinct.

Question 88

Figures 81a through 81c show the MRI scans of a 53-year-old man who has experienced a long history of progressively worsening right-sided back pain with radiation to the buttocks and right lower extremity. Examination reveals weakness and hyperreflexia in the right lower extremity. He reports intermittent episodes of urinary incontinence. What is the most appropriate surgical approach? Review Topic

Explanation

The presence of stenosis in the thoracic region with its related clinical manifestations has only recently been appreciated. The pathogenesis of thoracic stenosis is similar to that found in the cervical or lumbar spine. Two distinct clinical syndromes of thoracic stenosis have been identified, the most common being associated with degenerative changes of the spine. Clinical manifestations include development of unilateral or bilateral symptoms of pseudoclaudication. Focal radicular pain or paresthesias may also be present. The neurologic examination initially may be normal, but as the degree of neural compression progresses, posterior column dysfunction and long tract signs appear. If allowed to progress untreated, the patient may develop significant difficulty with gait and bowel/bladder function. Thoracic spinal cord stenosis secondary to congenital narrowing of the spinal canal is associated with a more abrupt onset of symptoms. The typical clinical manifestations of myelopathy may commence following minor or moderate trauma. Radicular symptoms are rare in congenital thoracic stenosis. One indication for thoracic laminectomy is a patient in whom imaging has demonstrated evidence of spinal canal stenosis secondary to hypertrophy of the posterior elements. A laminectomy should not be the primary approach when stenosis results from a significant ventral epidural osteophyte or herniated disk; these lesions are more effectively and safely managed by a posterolateral (transpedicular, transfacetal, or costotransversectomy) or an anterior approach.

Question 89

A patient reports pain in the hip with functional positioning. With the patient supine, pain in which of the following positions would be typical for femoral acetabular impingement?

Explanation

DISCUSSION: Patients with dysplasia often have a hypertrophic labrum. Abnormal contact between the femoral neck and the acetabular rim leads to labral injury, especially in the anterior-superior acetabular zone. Typically, young patients with the condition report pain with activity or long periods of sitting or driving. The hips often have limited motion, in particular in internal rotation and flexion. Forceful adduction with the maneuver causes pain.
REFERENCES: Vaccaro AR (ed): Orthopaedic Knowledge Update 8. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2005, pp 411-424.
Beck M, Leunig M, Parvizi J, et al: Anterior femoroacetabular impingement: Part II. Midterm results of surgical treatment. Clin Orthop 2004;418:67-73.
McCarthy JC, Noble PC, Schuck MR, et al: The role of labral lesions to development of early degenerative hip disease. Clin Orthop 2001;393:25-37.

Question 90

A 72-year-old woman who fell on her right shoulder while using a treadmill is now unable to elevate her right arm. An MRI scan is shown in Figure 7. What is the most likely diagnosis?

Explanation

DISCUSSION: The MRI scan reveals a large chronic rotator cuff tear with retraction and fatty infiltration atrophy of the supraspinatus and infraspinatus tendons. This tear is responsible for the patient’s severe weakness and inability to elevate the arm.
REFERENCE: Gerber C, Myer DC, Schneeberger AG, et al: Effect of tendon release and delayed repair on the structure of the muscles of the rotator cuff: An experimental study in sheep. J Bone Joint Surg Am 2004;86:1973-1982.

Question 91

Design and manufacturing of a metal-on-metal articulation has an important influence on the tribology. Which of the following statements best characterizes the type of contact that is best for metal-on-metal articulations?

Explanation

DISCUSSION: It is important that the radii of a metal-on-metal head to cup articulation be such that there is polar contact. As the radii become closer to equal, conditions favor higher frictional torque and equatorial seizing. The “bedding in” of metal-on-metal surfaces and their stiffness are both components of the properties considered in the design of polar contact surfaces.
REFERENCE: Pellicci PM, Tria AJ Jr, Garvin KL (eds): Orthopaedic Knowledge Update: Hip and Knee Reconstruction 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2000, pp 25-34.

Question 92

What joint always remains uninvolved in all stages of scapholunate advanced collapse (SLAC) deformity of the wrist?

Explanation

DISCUSSION: The development of arthritis in SLAC wrist follows a consistent pattern. Beginning at the radial styloid to the scaphoid articulation, it progresses through the entire radioscaphoid joint and the midcarpal joint. In all stages, the radiolunate joint is spared, which is the basis for a scaphoid excision and four-corner fusion performed as a motion-sparing procedure for treatment of this condition.
REFERENCES: Wyrick JD: Proximal row carpectomy and intercarpal arthrodesis for the management of arthritis. J Am Acad Orthop Surg 2003;11:277-281.
Watson HK, Ballett FL: The SLAC wrist: Scapholunate advanced collapse pattern of degenerative arthritis. J Hand Surg Am 1984;9:358-365.
Watson HK, Ryu J: Evolution of arthritis of the wrist. Clin Orthop 1986;202:57-67.

Question 93

The implant shown in Figures 47a and 47b is introduced submuscularly employing a minimally invasive technique. A percutaneous method of screw insertion is used distally. What nerve is most at risk?

Explanation

Minimally invasive methods used for stabilizing complex periarticular fractures continue to evolve. Encouraging results suggest a diminished threat to the soft tissues and enhanced preservation of osseous blood supply. Contemporary locking implants combined with indirect reduction lead to desirable biomechanical and biologic environments for osseous and soft-tissue healing. Deangelis and associates, in a cadaveric tibial study, demonstrated the superficial peroneal nerve to be at significant risk during percutaneous screw placement in very distal targeted holes (within laterally applied tibial locking plates). Use of a larger incision and cautious dissection to the plate in this region were encouraged to minimize risk to this structure.

Question 94

Which of the following is considered a limitation of the Short Form 36 (SF-36) general health status instrument when applied to musculoskeletal conditions?

Explanation

Health outcome surveys are often either general or condition specific. The SF-36 (a general health-based survey) is the most widely applied general health status instrument. It measures three aspects of health: functional ability, well being, and overall health. Eight domains of quality of life are measured to quantify these aspects. It is designed to be self-administered by the patient. Because it is a patient-derived assessment, with patient-derived outcome measures, the patient's perspective is integrated and objectivity enhanced. The inherent bias of surgeon-driven formats is thus avoided. The SF-36 has been validated and normative population data obtained.
Multilingual validated translations have been produced in addition to international population data sets. The survey can be patient self-administered via office visit, mail, or telephone. A bias of lower over upper extremity function with regard to outcome measures employing the SF-36 has been demonstrated. Limits on the detection of certain changes in quality of life status may impose ceiling and floor effects on analysis and interpretation.

Question 95

In patients undergoing elective hip or knee arthroplasty who are not at elevated risk (beyond the risk associated with the surgery) for venous thromboembolism or bleeding, using pharmacologic agents and/or mechanical compressive devices for the prevention of venous thromboembolism was assigned what grade of recommendation by the 2011 AAOS Clinical Practice Guideline, Preventing Venous Thromboembolic Disease in Patients Undergoing Elective Hip and Knee Arthroplasty?

Explanation

DISCUSSION:
Using pharmacologic agents and/or mechanical compressive devices for the prevention of venous thromboembolism in patients undergoing elective hip or knee arthroplasty who are not at elevated risk beyond that of the surgery itself for venous thromboembolism or bleeding was given a moderate grade of recommendation in the 2011 AAOS Clinical Practice Guideline referenced above.

Question 96

A 25-year-old man is brought to the emergency department following a motor vehicle accident. Extrication time was 2 hours, and in the field he had a systolic blood pressure by palpation of 90 mm Hg. Intravenous therapy was started, and on arrival in the emergency department he has a systolic blood pressure of 90 mm Hg with a pulse rate of 130. Examination reveals a flail chest and a femoral diaphyseal fracture. Ultrasound of the abdomen is positive. The trauma surgeons take him to the operating room for an exploratory laparotomy. At the conclusion of the procedure, he has a systolic pressure of 100 mm Hg with a pulse rate of 110. Oxygen saturation is 90% on 100% oxygen, and he has a temperature of 95.0° F (35° C). What is the recommended treatment of the femoral fracture at this time?

Explanation

DISCUSSION: This is a “borderline trauma” patient where serious consideration for damage control orthopaedic surgery is required. His prolonged hypotension, abdominal injury, and chest injury put him at higher risk for serious postinjury complications. Further surgery, such as definitive fracture fixation, adds metabolic load and injury to his system. It is prudent to consider femoral fracture stabilization with an external fixator until he is physiologically recovered as evidenced by a normal base excess and/or lactate acid levels, as well as all other parameters of resuscitation. A borderline patient has been described as polytrauma with an ISS > 20 and thoracic trauma (AIS > 2); polytrauma and abdominal/pelvic trauma (Moore > 3) and hemodynamic shock (initial BP < 90 mm Hg); ISS > 40; bilateral lung contusions on radiographs; initial mean pulmonary arterial pressure > 24 mm Hg; pulmonary artery pressure increase during intramedullary nailing > 6 mm Hg. Factors that worsen the situation following surgery include multiple long bones and truncal injury (AIS > 2), estimated surgery time of more than 6 hours, arterial injury and hemodynamic instability, and exaggerated inflammatory response (eg, Il-6 > 800 pg/mL). It is incumbent on the orthopaedic surgeon who is a member of the trauma team to make sure that he or she is aware of these factors and guides the team to the best patient care.
REFERENCES: Pape HC, Hildebrand F, Pertschy S, et al: Changes in the management of femoral shaft fractures in polytrauma patients: From early total care to damage control orthopaedic surgery. J Trauma 2002;53:452-461.
Bosse M, Kellam JF: Orthopaedic decision making in the multiple trauma patient, in Browner BD (ed): Skeletal Trauma, ed 3. Philadelphia, PA, WB Saunders, 2003, pp 133-146.

Question 97

A 25-year-old lineman is referred to your office for a second opinion. 1 year ago, he underwent an arthroscopic procedure for shoulder instability. He complains of persistent sense of instability despite the surgery. Which of the following is a contraindication to revision arthroscopic labral repair for recurrent anterior glenohumeral instability? Review Topic

Explanation

Capsular attenuation or postthermal capsular necrosis from prior thermal capsulorraphy is a contraindicated to arthroscopic repair.
Thermal capsulorrhaphy utilizes heat generated by radiofrequency or laser ablation to cause capsular shrinkage in an effort to treat shoulder instability. However, high recurrence rates have been found, especially around two to three weeks after the index procedure, when the capsular tissue is the weakest. In the setting of recurrence following thermal capsulorrhaphy, open revision is recommended.
Creighton et al. reported on a series of 18 patients undergoing revision arthroscopic stabilization. Of the 18, 3 failed with recurrent instability, all with previous thermal capsulorrhaphy.
Miniaci et al. reviewed the outcomes following thermal capsulorrhaphy noting high rates of recurrent instability, especially in the setting of initial treatment for multidirectional instability.
Park et al. reported on a series of 14 patients undergoing revision following thermal capsulorrhaphy. Ten out of 14 patients had signs of capsular thinning, insufficiency and attenuation.
Wong et al. surveyed 379 shoulder surgeons on the complications following thermal capsulorrhaphy. Capsular insufficiency and thinning were commonly associated with recurrent instability.
Hecht et al. performed thermal capsulorrhaphy and biomechanical analysis of the capsule in a sheep model. The authors found that the capsule was weakest at the 2-3 week post-operative timepoint, leading to the highest rate insufficiency, attenuation and mechanical failure at this time.
Incorrect answers:

Question 98

At the time of arthroscopy, a 9-year-old boy was found to have a Watanabe type II discoid lateral meniscus. What is the most appropriate treatment? Review Topic

Explanation

The Watanabe type II meniscus should only require saucerization for treatment because it is not unstable. The Watanabe classification defines 3 types of discoid mensici. In type I (stable, complete), the block-shaped lateral meniscus covers the entire lateral tibial plateau, whereas in type II (stable, partial), the lateral meniscus covers less than or equal to 80% of the tibial plateau. Type III discoid menisci (unstable, ligament of Wrisberg) appear to be normal except for a thickened posterior horn, but they lack posterior meniscal attachments, including the meniscotibial (ie, coronary) ligament. The type III discoid meniscus is stabilized only by the meniscofemoral ligament of Wrisberg. This results in hypermobility of the lateral meniscus at the posterior horn, which pulls into the intercondylar notch with knee extension, resulting in snapping knee syndrome. Complete menisectomy should be avoided if possible.

Question 99

What is the most common malignant bone tumor seen in patients with multiple hereditary exostosis?

Explanation

DISCUSSION: Secondary chondrosarcomas are most common in patients with multiple hereditary exostosis. Dedifferentiated chondrosarcoma is less common and refers to bone lesions in which a high-grade spindle cell sarcoma component is located immediately adjacent to a low-grade cartilage neoplasm. Mesenchymal chondrosarcoma, clear cell chondrosarcoma, and periosteal osteosarcoma are no more common in patients with multiple hereditary exostosis than in the general population.
REFERENCES: Mirra JM: Bone Tumors: Clinical, Radiologic, and Pathologic Correlations. Philadelphia, PA, Lea and Febiger, 1989, pp 1660-1669.
Simon MA, Springfield DS, et al: Common Malignant Bone Tumors: Chondrosarcoma. Surgery for Bone and Soft Tissue Tumors. Philadelphia, PA, Lippincott Raven, 1998, pp 275-286.

Question 100

A 51-year-old woman who underwent a total knee arthroplasty 14 months ago for severe degenerative arthritis now reports progressive pain, swelling, and buckling of the knee. She must use crutches and is unable to negotiate stairs. Laboratory testing reveals a normal erythrocyte sedimentation rate and C-reactive protein. Radiographs of the patient are shown in Figures 17a through 17c. What is the most important test to further evaluate this problem?

Explanation

DISCUSSION: The cause of subluxation in this patient is multifactorial, and includes a laterally positioned patellar component, a tibial tray that is internally rotated and translated to the medial side of the proximal tibial surface, and a femoral component that is markedly internally rotated about 10 degrees. All of these findings will be apparent on a CT scan. The long standing radiograph may be helpful but does not show the particular rotational abnormalities of both implants that are causing this problem. Fluoroscopic review may show how unstable the patella is, but the initial Merchant’s view shows the basic problem. A bone scan does not provide information about component malposition. An MRI scan is inferior to a CT scan because of image artifact.
REFERENCES: Stiehl JB: Patellar instability in total knee arthroplasty. J Knee Surg 2003;16:229-235. Berger RA, Crossett LS, Jacobs JJ, et al: Malrotation causing patellofemoral complications after total knee arthroplasty. Clin Orthop Relat Res 1998;356:144-153.

Full Question & Answer Text (for Search Engines)

Question 1:

Options:

Peroneal longus tendon
Peroneal brevis tendon
Superior peroneal retinaculum
Anterior talofibular ligament
Calcaneofibular ligament

Correct Answer: Superior peroneal retinaculum

Explanation:

DISCUSSION: The symptoms and MRI scan indicate dislocated peroneal tendons. In this patient, the structure that needs to be repaired is the superior peroneal retinaculum. If the popping was coming from a torn peroneal tendon, repair would involve the peroneal longus or brevis tendon, but this is not shown in the MRI scan. The anterior talofibular ligament or the calcaneofibular ligament would need to be repaired if the patient had ankle instability due to an ankle sprain.
REFERENCES: Jones DC: Tendon disorders of the foot and ankle. J Am Acad Orthop Surg 1993;1:87-94.
Timins ME: MR imaging of the foot and ankle. Foot Ankle Clin 2000;5:83-101.

Question 2:

Options:

The local Keyhole representative has invited you and your spouse out to dinner at a local restaurant to discuss your interest in their new minimally invasive total knee system, the Keyhole Genuflex knee.
Keyhole has offered to pay your tuition to attend a CME course sponsored by the American Association of Hip & Knee Surgeons where both the Genuflex and the competing Styph total knee are discussed and demonstrated.
Keyhole will pay your expenses to attend a workshop, in Phoenix at their company headquarters, to learn how to implant the Genuflex knee and to see how the implant is manufactured and tested.
Keyhole will pay you $500 for each knee that you implant if you switch from your current total knee system.
After you have implanted 25 Genuflex knees, Keyhole will list you on their website as a consultant, pay you a consulting fee of $5,000 per year, and invite you to a golf tournament for their consultants at a resort.

Correct Answer: Keyhole will pay your expenses to attend a workshop, in Phoenix at their company headquarters, to learn how to implant the Genuflex knee and to see how the implant is manufactured and tested.

Explanation:

Question 3:

Options:

Consultation with an infectious disease specialist
Symptomatic treatment, with a full return to activities in 4 to 6 weeks
Cast immobilization for 6 to 12 weeks with the expectation of full recovery
A rheumatologic work-up with the expectation of significant long-term sequelae
Bone biopsy

Correct Answer: Cast immobilization for 6 to 12 weeks with the expectation of full recovery

Explanation:

Question 4:

Options:

Adjunctive plate fixation without nail removal
Nail removal and plating
Partial fibulectomy at the same level as the tibia fracture and weightbearing cast application
Exchange nailing
Local administration of rhBMP-2

Correct Answer: Adjunctive plate fixation without nail removal

Explanation:

Question 5:

A 16-year-old boy sustains a twisting injury to the left knee while wrestling. MRI scans are shown in Figures 22a through 22c. What is the most likely diagnosis?

Options:

Anterior cruciate ligament rupture
Posterior cruciate ligament rupture
Bucket-handle medial meniscus tear
Lateral meniscus tear
Osteochondral lesion

Correct Answer: Bucket-handle medial meniscus tear

Explanation:

DISCUSSION: The MRI scans show a displaced bucket-handle medial meniscus tear that can be visualized on coronal, sagittal, and axial views. The sagittal view shows the typical “double posterior cruciate ligament sign,” in which the low-signal bucket-handle fragment parallels the normal low-signal posterior cruciate ligament. The coronal and axial images both show the displaced medial meniscus in the notch.
REFERENCES: Sanders TG, Miller MD: A systematic approach to magnetic resonance imaging interpretation of sports medicine injuries of the knee. Am J Sports Med 2005;33:131-148.
Miller TT: Magnetic resonance imaging of the knee, in Insall JN, Scott WN (eds): Surgery of the Knee, ed 4. Philadelphia, PA, Churchill Livingstone, 2006, vol 1, pp 201-224.

Question 6:

In surgically treating hand and finger infections in patients with diabetes mellitus, what factor is associated with higher amputation rates?

Options:

Insulin dependence
Gram-positive organisms
Renal failure
Retinopathy
Peripheral neuropathy

Correct Answer: Renal failure

Explanation:

DISCUSSION: Patients with diabetes mellitus are prone to infection, and surgical treatment of their infections frequently requires multiple procedures. The triad of poor wound healing, chronic neuropathy, and vascular disease contributes to the increased infection rate. Studies have demonstrated increased amputation rates in patients with diabetes mellitus who have renal failure or deep polymicrobial or gram-negative infections.
REFERENCES: Gonzalez MH, Bochar S, Novotny J, et al: Upper extremity infections in patients with diabetes mellitus. J Hand Surg Am 1999;24:682-686.
Trumble TE (ed): Hand Surgery Update 3: Hand, Elbow, & Shoulder. Rosemont, IL, American Society for Surgery of the Hand, 2003, pp 433-457.
Kour AK, Looi KP, Phone MH, et al: Hand infections in patients with diabetes. Clin Orthop Relat Res 1996;331:238-244.

Question 7:

Options:

Propionibacterium acnes
Staphylococcus aureus
Group B streptococcus
Neisseria gonorrhea
Enterococcus coli

Correct Answer: Enterococcus coli

Explanation:

This patient has sternoclavicular joint septic arthritis with gram positive organisms. Although there is an increased incidence of Pseudomonas aeruginosa infection in IV drug users, S. aureus is still the most common organism.
Ross et al states "Staphylococcus aureus is now the major cause of
sternoclavicular septic arthritis in intravenous drug users. Pseudomonas aeruginosa infection in injection drug users declined dramatically with the end of an epidemic of pentazocine abuse in the 1980s."
The referenced article by Goldin et al is from the New England Journal of Medicine reports that all of their cases of SC joint septic arthritis were in intravenous drug abusers and that P. aeruginosa grew out of 3 patients and S. aureus grew out of 1 patient.
A more recent article by Abu Arab et al reported that Staph aureus was most common even in IV drug users. The review article by Higginbotham and Kuhn note that risk factors for SC joint septic arthritis include hemodialysis, immunocompromise, alcoholism, and HIV. Neisseria gonorrhoeae, fungal, and candida present in HIV patients.
Treatment is I&D and appropriate antibiotics, although aspiration and abx have shown some success too. CT and MRI are useful in diagnosis, and open biopsy or aspiration is recommended for definitive diagnosis.
A 30-year-old man presents with a distal third tibia fracture that has healed in 25 degrees of varus alignment. The patient is at greatest risk of developing which of the following conditions as a result of this malunion?
Degenerative lumbar spine changes
Ipsilateral ankle pain and stiffness
Ipsilateral hip joint degenerative changes
Contralateral hip joint degenerative changes
Ipsilateral medial knee degenerative changes
Correct answer: 2
A significant malunion of the distal tibia has important consequences for patient outcome, including pain, gait changes, and cosmesis.
The first referenced article by Milner et al looked at long-term outcomes of tibial malunions and noted that varus malunion led to increased ankle/subtalar stiffness and pain regardless of the amount of radiographic degenerative changes.
The second referenced article by Puno et al reinforced the concept of decreased functional outcomes of the ankle with tibial malunions, and noted
that other lower extremity joints (ipsilateral and contralateral) do not have increased rates of degeneration from such a malunion.
A 33-year-old man sustains a femur fracture in a motorcycle accident. AP and lateral radiographs are provided in Figure A. Prior to surgery, a CT scan of the knee is ordered for preoperative planning. Which of the following additional findings is most likely to be discovered?
Tibial eminence fracture
Sagittal plane fracture of the medial femoral condyle
Schatzker I tibia plateau fracture
Coronal plane fracture of the lateral femoral condyle
Axial plane fracture through the medial femoral condyle
Correct answer: 4
The "Hoffa fracture" is a coronal plane fracture of the femoral condyle that is often missed on plain radiographs of supracondylar and intercondylar femur fractures. It involves the lateral condyle more frequently than the medial.
Identification is important as it may impact operative planning and likely require screw fixation in the anteroposterior plane.
Nork et al. reviewed 202 supracondylar-intercondylar distal femoral fractures and found a 38% prevalence of associated coronal plane fractures. The authors recommend CT scan imaging of all supracondylar and intercondylar fractures.
Ostermann et al reported on 24 unicondylar fractures of the distal femur treated with open reduction internal fixation with a screw construct. Twenty-
three patients acheived satisfactory results at 5 year follow-up. Illustrations A and B are another example of a supracondylar femur fracture with an associated Hoffa fracture identified on CT scan.
A 35-year-old woman presents with an elbow injury which includes a coronoid fracture involving more than 50%, a comminuted
radial head fracture, and an elbow dislocation. What is the most appropriate treatment?
closed reduction and early range of motion
radial head resection and lateral collateral ligament reconstruction
radial head resection and coronoid open reduction internal fixation
radial head arthroplasty and coronoid open reduction internal fixation
radial head arthroplasty, coronoid open reduction internal fixation, and lateral collateral ligament repair
A terrible triad of the elbow includes dislocation of the elbow with associated fractures of the radial head and the coronoid process. Ring et al. stressed that these injuries are prone to complications and advised against resection of the radial head due to instability, and instead recommended a radial head replacement if too comminuted for ORIF. Coronoid fractures compromise elbow stability as well and require open reduction and internal fixation as with the lateral collateral ligament. McKee et al. showed stable elbows in 34/36 with mean Mayo elbow score of 88 when the standard protocol of coronoid ORIF, radial head repair/replacement, and LCL repair were employed.
The talocrural angle of an ankle mortise x-ray is formed between a line perpendicular to the tibial plafond and a line drawn:
perpendicular to the medial clear space
parallel to the talar body
between the tips of the malleoli
perpendicular to the shaft of the fibular
parallel to the subtalar joint
Correct answer: 3
The talocrural angle is formed by the intersection of a line perpendicular to the plafond with a line drawn between the malleoli (average = 83+/-4deg). When the lateral malleolus is shortened secondary to fracture, this can lead to increased talocrural angle. This malunion leads to lateral tilt of the talus.
Phillips et al looked at 138 patients with a closed grade-4 supination-external rotation or pronation-external rotation ankle fracture. Although the conclusions were limited due to poor follow up, they found the difference in the talocrural angle between the injured and normal sides was a statistically significant radiographic indicator of a good prognosis.
Pettrone et al looked at a series of 146 displaced ankle fractures, and the effect of open or closed treatment, and internal fixation of one or both malleoli. They found open reduction proved superior to closed reduction, and in bimalleolar fractures open reduction of both malleoli was better than fixing only the medial side.
Illustrations A and B are demonstrations of the talocrural angle.
A 33-year-old male sustains the injury shown in Figure A. He is initially treated with a spanning external fixator followed by definitive open reduction internal fixation of the tibia and fibula. His wounds healed without infection or other complications. Two years following surgery, which of the following parameters will most likely predict a poor clinical outcome and inability to return to work?
Joint line restoration
Degree of fracture displacement
Time before definitive ORIF
Open fracture
Lower level of education
Correct answer: 5
Lower level of education is the parameter that correlated most closely with a poor clinical outcome and inability to return to work.
To determine what fracture- and patient-specific variables affect outcome, Williams et al evaluated 29 patients with 32 tibial plafond fractures at a minimum of 2 years from the time of injury. Outcome was assessed by four independent measures: a radiographic arthrosis score, a subjective ankle score, the Short Form-36 (SF-36), and the patient’s ability to return to work. The four outcome measures did not correlate with each other. Radiographic arthrosis was predicted best by severity of injury and accuracy of reduction. However, these variables did not show any significant relationship to the clinical ankle score, the SF-36, or return to work. These outcome measures were more influenced by patient-specific socioeconomic factors. Higher ankle
scores were seen in patients with college degrees and lower scores were seen in patients with a work-related injury. The ability to return to work was affected by the patient’s level of education.
Pollak et al performed a retrospective cohort analysis of pilon fractures. Patient, injury, and treatment characteristics were recorded. The primary outcomes that were measured included general health, walking ability, limitation of range of motion, pain, and stair-climbing ability. A secondary outcome measure was employment status. Multivariate analyses revealed that presence of two or more comorbidities, being married, having an annual personal income of less than $25,000, not having attained a high-school diploma, and having been treated with external fixation with or without limited internal fixation were significantly related to poorer results as reflected by at least two of the five primary outcome measures.
What is the most appropriate treatment for a 17-year-old boy who sustained a gunshot wound to his forearm from a handgun with a muzzle-velocity of 1000 feet/second if he is neurovascularly intact and radiographs reveal no fracture?
Irrigation and local wound care in the emergency department
Emergent irrigation and debridement in the operating room with vacuum-assisted wound closure
Emergent irrigation and debridement in the operating room with 7 days of intravenous antibiotics
Wound closure in the emergency department with follow-up wound check in 1 week
Exploration and removal of all bullet fragments in the emergency department and 10 day course of oral antibiotics
The question refers to appropriate management of a gunshot wound to the forearm. The first question that must be answered when evaluating gunshot injuries is whether the gunshot is low velocity or high velocity. Low-velocity wounds are less severe, are more common in the civilian population, and are typically attributed to bullets with muzzle velocities below 1,000 to 2,000 feet per second. Tissue damage is usually more substantial with higher-velocity (greater than 2,000 to 3,000 fps) military and hunting weapons. In this question, a muzzle velocity of 1,000 ft/sec is provided. Low velocity injuries with stable, non-operative fractures can be treated with local wound care.
The two referenced articles offer guidance for treating low-velocity gunshot injuries with stable, non-operative fracture patterns. The first article by Geissler et al is a retrospective study comparing 25 patients that prospectively received local irrigation and debridement, tetanus prophylaxis and a long acting cephalosporin intramuscularly to a random retrospective sample of 25 patients with similar ballistic-induced fractures and wounds managed by local debridement and 48h of intravenous antibiotics. One infection occurred in each group, requiring further therapy. It was concluded that patients with low-velocity gunshot induced fractures can be managed without the use of short-term intravenous antibiotics with no increased risk of infection.
In the second study, Dickey et al evaluated the efficacy of an outpatient management protocol for patients with a gunshot-induced fracture with a stable, non-operative configuration. 41 patients with a grade I or II open, nonoperative fracture secondary to a low-velocity bullet were treated with 1gm of cefazolin administered in the emergency room and a 7-day course of oral cephalexin. No patient developed a deep infection. Thus, local I&D, tetanus, and oral antibiotics for 2-3 days is adequate for low velocity gunshot wounds.
Which clinical sign is the most sensitive for the diagnosis of compartment syndrome in a child with a supracondylar humerus fracture?
pulselessness
pallor
paresthesia
paralysis
increasing analgesia requirement
Correct answer: 5
Although pain, pallor, paresthesia, paralysis, and pulselessness are all possible signs and symptoms of compartment syndrome in children with fractures, studies have shown increasing analgesia requirement is more sensitive.
Bae et al reviewed thirty-six cases of compartment syndrome in 33 pediatric patients. Approximately 75% of these patients developed compartment syndrome in the setting of fracture. "They found pain, pallor, paresthesia, paralysis, and pulselessness were relatively unreliable signs and symptoms of compartment syndrome in these children. An increasing analgesia requirement in combination with other clinical signs, was a more sensitive indicator of
compartment syndrome."
Whitesides et al summarizes the diagnosis and treatment of acute compartment syndrome. They emphasize the need for early diagnosis, as "muscles tolerate 4 hours of ischemia well, but by 6 hours the result is uncertain; after 8 hours, the damage is irreversible." They recommend fasciotomy be performed when tissue pressure rises past 20 mm Hg below diastolic pressure.
A 45-year-old man sustains the injury seen in Figures A and B following a motor vehicle accident. Postoperative radiographs are seen in Figures C and D. Which of the following is the most accurate when comparing outcomes between intramedullary nailing (IMN) and open reduction internal fixation (ORIF) for this injury?
Union rates at one year are higher with ORIF
Infection rates are higher with IMN
Functional shoulder outcomes at one year are equivalent with IMN and ORIF
Iatrogenic radial nerve injury rate is higher with ORIF
Shoulder stiffness rates at one year are equivalent with IMN and ORIF
Correct answer: 3
Although shoulder pain and stiffness is increased following IMN compared to ORIF, functional outcome scores at one year have been shown to be equivalent
in both treatment groups.
Diaphyseal humeral shaft fractures outcomes following IMN and ORIF are under further investigation. Diaphyseal humeral shaft fractures have historically been treated with ORIF, however proponents for IMN cite benefits of less periosteal stripping and soft tissue dissection. Recent investigations have shown outcomes with regard to nonunion, infection, re-operation, and nerve palsy appear equivalent between both groups. Rates of shoulder stiffness and shoulder pain have been demonstrated to be higher in IMN compared to ORIF. American Shoulder and Elbow Scores (ASES) have shown no difference at one year post-operatively.
Bhandari et al. performed a meta-anaylsis of 3 prospective randomized trials. They found lower rates of re-operation and shoulder impingement with ORIF of humeral shaft fractures.
Wali et al. performed a prospective randomized study of IMN or ORIF on 50 patients with mid-diaphyseal humeral shaft fractures. They found IMN had shorter operative time, shorter hospital stay, and lower blood loss. They found no difference in union rates, complication, or shoulder functional outcomes scores. They conclude IMN to be an effective option for treating mid-diaphyseal humeral shaft fractures.
Heineman et al. have recently conducted an update on their meta-analysis to include more recent randomized studies. With the inclusion of newer studies the author found a statistically significant increase in total complication rate with the use of IM nailing compared with ORIF. The authors found no significant difference between the two treatment modalities for the secondary outcomes (nonunion, infection, nerve palsy, re-operation).
Figures A and B show a diaphyseal humeral shaft fracture. Figure C and D show postoperative radiographs following intramedullary nailing of a humeral shaft fracture.
Incorrect Answers:
A 25-year-old female presents complaining of progressive anteromedial pain in her left ankle. She underwent operative fixation 5 months prior at an outside hospital. The operative report indicated that, due to anterior fracture blisters, a direct medial incision was utilized, centered over the posterior colliculus of the medial malleolus, without violation of the deltoid ligament. A radiograph and computed tomographic scan of her initial injury are shown in Figures A and B, respectively. On exam, she has well-healed incisions, exhibits no tenderness to palpation over her hardware, but does endorse pain with deep palpation along the anteromedial joint line. Figure C shows an anteroposterior left ankle radiograph taken today. Labs are obtained and reveal a white blood cell count of 9.0 k/uL (reference range 4.5-11.0 k/uL) and a C-reactive protein value of 0.8 mg/dL (<0.9 mg/dL). What is the next best step in managing her problem?
Syndesmotic fixation
Intra-articular corticosteroid injection
Referral to physical therapy
Surgical correction of malunion
Removal of hardware
Correct answer: 4
This patient sustained a supination-adduction (SAD) injury with a vertical shear fracture of her medial malleolus and a fibular avulsion fracture. She sustained a medial plafond articular impaction injury that was not addressed at the time of surgery.
In SAD injuries, supination of the foot is combined with inward rotation at the ankle, adduction of the hindfoot, and inversion of the forefoot. This results in the following sequence of events: 1. Talofibular sprain or distal fibular avulsion (equivalent to Weber A). 2. Vertical medial malleolus fracture as the talus strikes the tibia. Associated injuries may include osteochondral damage to the talus and marginal impaction of the medial plafond. It is important to evaluate the medial plafond for articular impaction. When present, an arthrotomy must be performed, typically utilizing an anteromedial incision, with direct visualization of the articular surface to restore the joint line appropriately.
Weber et al. provided a review article on corrective osteotomies for malleolar fracture malunions. They stress that malunions can lead to ankle instability, abnormal load transfer, and post-traumatic arthritis. They conclude that corrective osteotomies that restore anatomical alignment show good results in long-term follow-up.
Perera et al. provided additional commentary on the surgical reconstruction of malunited ankle fractures. The authors emphasize the link between malunion and poor outcomes. They state that successful salvage procedures involve a clear understanding of the deformity, careful preoperative planning, and a solid understanding of reconstructive techniques. They provide several instructive case examples in their review.
McConnell et al. provided a discussion on SAD ankle fractures at their institution and emphasized the importance of recognizing marginal impaction of the tibial plafond when treating these injuries. Of 800 ankle fractures identified over a 5-year period, 44 were SAD injuries, 19 of the 44 displayed a vertical shear fracture of the medial malleolus, and 8 of the 19 demonstrated marginal impaction of the tibial plafond. These 8 impaction injuries were treated with open reduction internal fixation with elevation of the articular impaction; all had good to excellent outcomes without arthritic changes at last
follow-up.
Figure A is an anteroposterior left ankle radiograph demonstrating a SAD injury with a vertical shear fracture of the medial malleolus, a fibular avulsion fracture, and articular impaction of the medial tibial plafond. Figure B is a coronal CT demonstrating articular impaction of the medial plafond. Illustration A is an intra-operative photograph with the medial malleolus retracted allowing inspection of the articular surface; mild anteromedial plafond impaction is present.
Incorrect Answers:
A 90-year-old female slips and falls at home. She is a community ambulator and has no medical problems. She reports right hip pain at this time. Injury radiographs are shown in Figures A & B. Delay of more than 48 hours may result in:
Increased intraoperative time
Increased 30-day mortality
No impact on the rate of postoperative pneumonia
Higher rates of blood transfusion
Increased risk of post-operative infection
Correct answer: 2
Figures A & B demonstrate a right, unstable intertrochanteric femur fracture. Surgical stabilization within 48 hours improves short-term and 30-day mortality.
Hip fractures are common and mortality rates vary. In the elderly, mortality rates may reach 10% at 1-month, 20% at 4-months, and 30% at 1-year. Time to surgery has found to be a decisive factor. A pre-operative delay may lead to an increase in mortality and adversely influence other clinical outcomes.
Clinical guidelines recommend immediate operative stabilization, given the patient is medically fit for surgery.
Nyholm et al. performed a retrospective study of the Danish Fracture Database to investigate whether a surgical delay increases 30-day and 90-day mortality rates for patients with proximal femoral fractures. The 30-day and 90-day mortalities were 10.8% and 17.4%, respectively. The risk of 30-day mortality increased with increasing time intervals of more than 12 hours, 24 hours, and more than 48 hours. 90-day mortality increased with a surgical delay of more than 24 hours. They conclude that rapid surgical treatment should be performed by attending orthopaedic surgeons.
Moja et al. performed a meta-analysis and meta-regression to assess the relationship between surgical delay and mortality in elderly patients with a hip fracture. They analyzed 35 independent studies with 191,873 patients and 34,448 deaths. The majority of studies had a cut-off of 48 hours. They report that early hip surgery was associated with a lower risk of death and pressure sores. They conclude that early hip fracture surgery appears to provide a survival benefit compared to later intervention.
Rodriguez-Fernandez et al. performed a study examining 2 groups with hip fractures. The first group was studied retrospectively and had an average delay of surgical treatment of more than 1-week while the second group was studied prospectively, and had surgical treatment within 48 hours. They found a larger number of complications in the group with a delay in surgical treatment. They conclude that elderly patients with hip fractures should be treated as soon as their medical condition permits.
Figures A and B are the AP and lateral radiographs demonstrating a right, unstable intertrochanteric femur fracture. Illustration A is an intertrochanteric femur fracture, stabilized with a cephalomedullary nail.
Incorrect Answers:
A 22-year-old healthy left hand dominant male presents to the ED with left shoulder pain after falling from an ATV. Figure A is the radiograph of his left clavicle. He is neurovascularly intact and there is no evidence of skin tenting or open fracture. Which of the following most predisposes this patient to nonunion?
Diaphyseal fracture
Fracture displacement
Age
Male Gender
Injury involving the dominant extremity
Correct answer: 2
Displaced clavicle fractures are associated with higher rates of nonunion.
Nonunion occurs in roughly 5-6% of clavicle fractures and can result in slower functional return, poor cosmesis and muscle fatigability. Clavicle fractures can be sub-classified using the Allman classification into medial, diaphyseal, and lateral injuries (Illustration A). The Neer classification for diaphyseal injuries describes fractures as "nondisplaced" (less than 100% displacement) and "displaced" (greater than 100% displacement).
Robinson et al. performed a prospective cohort study to identify risk factors for nonunion after nonoperative management of clavicle fractures. The overall nonunion rate was 6.2% and was highest in lateral third fractures (11.5%).
Diaphyseal fractures had the lowest nonunion rate (4.5%). Additionally, the authors found that the risk for nonunion was increased by advancing age, female gender, fracture displacement, and comminution.
Jorgensen et al. performed a systemic review of the literature looking for predictors of non-union and malunion in mid shaft clavicle fractures treated non-operatively. They found fracture comminution, displacement, older age, female gender, and the presence of smoking to be his factors for non-union. Of these, displacement was the most likely factor that can be used to predict nonunion.
Figure A demonstrates a displaced left clavicle diaphyseal fracture. Note that the medial fragment is displaced superiorly by the deforming force of the sternocleidomastoid. Illustration A represents the Allman classification.
Illustration B demonstrates the deforming forces acting on the clavicle.
Incorrect Answers:
A 24-year-old male presents with ankle pain after being involved in a motor vehicle accident. His injury radiograph is shown in Figure A. Which of the following has been shown to contribute to the development of post-traumatic arthritis in this injury pattern?
Initial superficial zone cartilage cell death via apoptosis at the fracture margins
Initial superficial zone cartilage cell death via apoptosis remote from the fracture margins
Initial superficial zone cartilage cell death via necrosis remote from the fracture margins
Initial superficial zone cartilage cell death via necrosis at the fracture margins
Delayed superficial zone cartilage cell death via necrosis at the fracture margins
Figure A demonstrates a tibial plafond fracture. Initial superficial zone cartilage cell death via necrosis at the fracture margins has been shown to contribute to post-traumatic arthritis.
Post-traumatic osteoarthritis typically occurs after an intra-articular fracture. Impacted chondrocytes die by either necrosis or apoptosis, which have both been implicated in post-traumatic osteoarthritis. Initial cell death in the superficial cartilage zones at the fracture margins occurs by necrosis. Apoptosis occurs in a delayed fashion and is mitigated by several bioactive agents.
Apoptosis also affects the superficial cartilage zones near the fracture margins. Deep cartilaginous zones and areas away from the fracture margins do not seem to be involved in these processes.
McKinley et al. performed a review of the basic science of intra-articular fractures and posttraumatic osteoarthritis. They report that initial damage to the cartilage in combination with the ensuing pathomechanical and pathobiologic response of the cartilage after a fracture contribute to posttraumatic arthritis. Chronic abnormal joint loading is also thought to contribute to this process as well. They conclude that the relative contribution of each is unknown.
Tochigi et al. performed a study to determine the distribution and progression of chondrocyte damage after intra-articular ankle fractures. They harvested 7 normal human ankles and subjected them to impaction. They found that immediate superficial zone chondrocyte death was greater in fracture-edge regions than on-fracture regions. Subsequent cell death over the next 48 hours was significantly higher in fracture-edge regions as well. They conclude that cartilage damage in intra-articular fractures was characterized by chondrocyte death at fracture margins.
Figure A is an ankle mortise radiograph demonstrating an intra-articular tibial plafond fracture.
Incorrect Answers:
A 35-year-old male presents with left knee pain after sustaining the injury seen in Figure A. He is neurovascularly intact and can perform a straight leg raise, but has pain with passive range of motion. Figures B and C show an anteroposterior and lateral radiograph of the left knee, respectively. 175 cc of saline is injected into the superolateral quadrant with no egress of fluid from the inferolateral
laceration. What percentage of traumatic arthrotomies would be detected with this test?

Question 8:

A 6-year-old girl is referred for the elbow injury seen in Figure 2. What is the most appropriate treatment?

Options:

Immobilization in a long arm cast for 3 weeks
Immobilization in a long arm cast for 8 weeks
Open reduction and immobilization in a long-arm cast for 3 weeks
Open reduction and internal fixation with smooth pins
Open reduction and internal fixation with a screw

Correct Answer: Open reduction and internal fixation with smooth pins

Explanation:

DISCUSSION: The patient has a displaced lateral condyle fracture; therefore, simple immobilization for 3 to 8 weeks is likely to result in malunion or nonunion. Closed reduction of such injuries is rarely successful. The fracture is unstable, so fixation is required after open reduction. Because the fixation must cross the physis, smooth pins are indicated for the skeletally immature elbow. Open reduction with fixation has been shown to reduce the risk of delayed union and malunion.
REFERENCES: Beaty JH, Kasser JR: The elbow: Physeal fractures, apophyseal injuries
of the distal humerus, avascular necrosis of the trochlea, and T-condylar fractures, in Beaty JH, Kasser JR (eds): Fractures in Children, ed 5. Philadelphia, PA, Lippincott Williams & Wilkins, 2001, pp 625-703.
Rutherford A: Fractures of the lateral humeral condyle in children. J Bone Joint Surg Am 1985;67:851-856.
Hasler CC, von Laer L: Prevention of growth disturbances after fractures of the lateral humeral condyle in children. J Pediatr Orthop B 2001;10:123-130.

Question 9:

The radiograph shown in Figure 54 reveals that the plate on the second metacarpal is acting in what manner?

Options:

Compression plate
Tension band plate
Bridge plate
Buttress plate
Spring plate

Correct Answer: Bridge plate

Explanation:

DISCUSSION: There are four ways in which a plate acts: compression, tension bend, bridge or spanning, and buttress. Since there is no cortical contact with the large span of comminution, this plate is acting as a bridge plate. A bridge plate is defined as when the plate is used as an extramedullary splint attached to the two main fragments, leaving the comminution untouched.
REFERENCE: Ruedi T, Murphy WM (eds): AO Principles of Fracture Management. New York, NY, Thieme, 2000, p 221.

Question 10:

A college basketball player is struck in the eye by a player’s hand while driving to the basket. Fluorescein evaluation reveals the injury shown in Figure 18. Management should consist of

Options:

administration of ophthalmic corticosteroids and antibiotics with application of an eye patch.
evaluation of intact visual fields and pupillary responses prior to a return to play.
consultation with an ophthalmologist prior to emergent repair of the damaged structure.
measurement of ocular pressure and fundoscopic examination in a properly lit examination room.
strict bed rest with the head elevated, minimizing head motion during the healing process.

Correct Answer: administration of ophthalmic corticosteroids and antibiotics with application of an eye patch.

Explanation:

Question 11:

Excision of heterotopic bone about the forearm or elbow can be done with limited recurrence rates as early as which of the following after initial injury?

Options:

Once ankylosis of the forearm or elbow occurs
6 weeks
6 months
12 months
18 months

Correct Answer: Once ankylosis of the forearm or elbow occurs

Explanation:

Question 12:

Which of the following is most associated with local recurrence of the lesion seen in the radiograph and MRI scan shown in Figures 27a and 27b?

Options:

Effectiveness of chemotherapy
Effect of local adjuvant
Open physes
Presence of giant cells
Effectiveness of embolization

Correct Answer: Open physes

Explanation:

DISCUSSION: The lesion is an aneurysmal bone cyst. These lesions are known to have a local recurrence rate of 5% to 50%. Young age, open physes, stage, and type of surgical removal and resulting margin have all been shown to affect the recurrence rate. Chemotherapy is not used in the treatment of aneurysmal bone cysts.
REFERENCES: Gibbs CP Jr, Hefele MC, Peabody TD, et al: Aneurysmal bone cyst of the extremities: Factors related to local recurrence after curettage with a high-speed burr. J Bone Joint Surg Am 1999;81:1671-1678.
Vergel De Dios AM, Bond JR, Shives TC, et al: Aneurysmal bone cyst: A clinicopathologic study of 238 cases. Cancer 1992;69:2921-2931.

Question 13:

Options:

Order an urgent angiogram and then proceed to the OR
Repeat the reduction in the emergency department and reassess.
Perform open reduction through an anterior approach.
Perform closed reduction and pinning in the OR and reassess the vascular status.
Perform arterial repair and then stabilize the fracture.

Correct Answer: Perform closed reduction and pinning in the OR and reassess the vascular status.

Explanation:

Question 14:

Integrins function in which of the following ways?

Options:

Maintain bone and cellular matrix
Form bone by producing non-mineralized matrix
Form cartilage under intermediate strain and low oxygen tension
Attachment of osteoclasts to bone surfaces
Binds to RANKL on the osteoblast, preventing RANK activation

Correct Answer: Binds to RANKL on the osteoblast, preventing RANK activation

Explanation:

Question 15:

Options:

observation.
varus prevention orthoses.
physeal bar resection.
proximal tibial osteotomy that produces a neutral mechanical axis.
proximal tibial osteotomy that produces 10 degrees of valgus.

Correct Answer: proximal tibial osteotomy that produces 10 degrees of valgus.

Explanation:

Question 16:

- In a fatigue test, the maximum stress under which the material will not fail, regardless of how many loading cycles are applied, is defined as

Options:

Endurance limit
Failure stress
Critical stress
Yield stress
Elastic limit

Correct Answer: Endurance limit

Explanation:

Question 17:

Options:

Aneurysmal bone cyst
Giant cell tumor
Renal cell carcinoma
Osteomyelitis
Brown tumor

Correct Answer: Giant cell tumor

Explanation:

Question 18:

Options:

Hemiarthroplasty
Arthroscopic debridement
Total shoulder arthroplasty with a cemented all-polyethelene glenoid component
Reverse total shoulder arthroplasty
Total shoulder arthroplasty with a metal-backed glenoid component

Correct Answer: Total shoulder arthroplasty with a cemented all-polyethelene glenoid component

Explanation:

DISCUSSION: Most studies have shown that total shoulder arthroplasties yield better pain relief and improved forward elevation when compared to hemiarthroplasty in patients with rheumatoid arthritis. Although rotator cuff tears are more common in this patient population, this patient has good forward elevation and no significant superior migration of the humeral head; therefore, a reverse arthroplasty is not indicated. The arthritis is too advanced in this patient to consider arthroscopy, but in less advanced cases it can improve range of motion and decrease pain. Metal-backed glenoid components have shown higher rates of loosening.
REFERENCES: Collin DN, Harryman DT II, Wirth MA: Shoulder arthroplasty for the treatment of inflammatory arthritis. J Bone Joint Surg Am 2004;86:2489-2496.
Baumgarten KM, Lashgari CM, Yamaguchi K: Glenoid resurfacing in shoulder arthroplasty: Indications and contraindications. Instr Course Lect 2004;53:3-11.
Martin SD, Zurakowski D, Thornhill TS: Uncemented glenoid component in total shoulder arthroplasty: Survivorship and outcomes. J Bone Joint Surg Am 2005;87:1284-1292.

Question 19:

What is the standard interval for placement of an anterolateral portal in ankle arthroscopy?

Options:

Peroneus brevis to peroneus longus
Peroneus tertius to extensor hallucis longus
Peroneus tertius to superficial peroneal nerve
Extensor hallucis longus to deep peroneal nerve
Extensor hallucis longus to extensor digitorum longus

Correct Answer: Peroneus tertius to superficial peroneal nerve

Explanation:

Question 20:

Options:

Will result in improvement in pain but no difference in function or range of motion compared to therapy alone.
Will result in greater improvement in pain and function compared to therapy alone, with equivalent range of motion at one year
Will prevent development of rotator cuff arthropathy in patients with rotator cuff tears.
Will likely have no effect on pain, function or range of motion at one year, compared to therapy alone.
Will result in worse outcomes in terms of pain, function and range of motion, compared with therapy alone.

Correct Answer: Will result in worse outcomes in terms of pain, function and range of motion, compared with therapy alone.

Explanation:

Question 21:

In an isolated ankle syndesmotic injury, the fibula is unstable in the incisura fibularis of the tibia. In what direction is the fibula most unstable?

Options:

Anterior-posterior
Medial-lateral
Proximal-distal
Rotational
Equivalent instability in all axes

Correct Answer: Anterior-posterior

Explanation:

Question 22:

Options:

continued physical therapy that focuses on stretching and advances to strengthening in 4 weeks.
a cortisone injection into the subacromial space.
revision rotator cuff repair.
a sling with an abduction pillow for 2 weeks, followed by a stretching program.
open rotator cuff debridement without repair.

Correct Answer: revision rotator cuff repair.

Explanation:

Question 23:

This reporting avoids a ceiling and floor effect, where most of the respondents score either at the top or the bottom of the assessment scale.

Options:

Brodke et al. performed a comparative study of the psychometric properties of
the PROMIS physical function domain, the Oswestry Disability Index (ODI), and the Short Form 36 (SF-36) questionnaire in the spine population. They reported that the PROMIS PF CAT required less time and had less ceiling and floor effects than the ODI and SF-36 questionnaires. Additionally, there was a high correlation between the three evaluation methods. They concluded that the PROMIS system provides better outcomes assessment while taking less time and fewer questions than legacy tests.
Brodke et al. reviewed the literature regarding the use of the PROMIS outcomes measure for several orthopedic conditions. The use of the computerized adaptive testing version allows for a higher level of precision with fewer questions administered and reduced time. In the spine literature, the PROMIS system has shown a reduced ceiling and floor effect compared to other legacy tests. They concluded that this system provides a highly reliable and valid means of measuring patient-reported outcomes while reducing respondent and administrative burden.
Incorrect Answers:

Correct Answer: Brodke et al. reviewed the literature regarding the use of the PROMIS outcomes measure for several orthopedic conditions. The use of the computerized adaptive testing version allows for a higher level of precision with fewer questions administered and reduced time. In the spine literature, the PROMIS system has shown a reduced ceiling and floor effect compared to other legacy tests. They concluded that this system provides a highly reliable and valid means of measuring patient-reported outcomes while reducing respondent and administrative burden.

Explanation:

Which of the following statistical tools is used to determine responsiveness?
The only accurate statement is that, at 1 month, patients in group 3 are more likely to live longer than patients in group 1 and 2.
The Kaplan-Meier curve is a statistical method used in survivorship analysis to estimate survival rates at different time points. The horizontal axis depicts the time points and the vertical axis depicts the probability of survival. At a given time point, greater survivorship is demonstrated by higher values on the vertical axis.
Kocher et al. reviewed clinical epidemiology and biostatistics relevant in orthopaedic
surgery. They reported that survivorship data are typically analyzed with use of the Kaplan-Meier method. This analysis is used when the actual date of the end point is known. A survivorship curve can be plotted to illustrate the percentage of patients still alive after the intervention.
Petrie et al. reviewed statistics, terminology and the principles involved in simple data analysis, and outlines areas of medical statistics that have gained
prominence in recent years in orthopaedic papers. The authors provide an insight into some of the more common errors that occur in published orthopaedic journals and which are frequently encountered at the review stage in papers submitted to the Journal of Bone and Joint Surgery.
Figure A depicts a Kaplan-Meier curve for 3 groups of patients undergoing 3 different interventions.
Incorrect Answers:
When evaluating patient-reported outcomes in spine surgery, the Patient- Reported Outcomes Measurement Information System (PROMIS) has been found to have what differences compared to other assessment tools?
Communication failures have been associated with increased treatment costs, increased complications, and delays in patient care.
The leading cause of medical errors, wrong-site surgeries, diagnostic delays and loss to follow-up is attributed to communication errors. Studies have shown that this directly leads to increased complications, increased treatment costs, and delays in patient care. In the surgical setting, the performance of the pre-surgical time-out affords clarification of the treatment plan, confirmation of the procedure and site, and an opportunity for the team to address any concerns.
Weller et al. reviewed barriers to effective teamwork in healthcare delivery. They found that effective communication across all team members, inclusive training, and the creation of democratic teams can reduce treatment delays and minimize complications. They concluded that all team members should have a shared understanding of the situation when involved in patients care.
Lingard et al. performed a prospective study determining the feasibility of a preoperative 10-item checklist discussion including nurses, surgeons, and anesthesiologists. They reported that the discussion usually took place prior to bringing the patient to the OR and took on average 3.5 minuted. Overall, the guided discussion was very well received by participants and provided an opportunity to inform providers of the patient's information to address potential problems. The authors cited that variations in workflow patterns as a potential barrier to widescale implementation of the checklist discussion.
Incorrect answers:
The outcomes of three novel interventions are investigated and the preliminary results are depicted in Figure A. Which of the following statements is most accurate?
Linezolid acts to inhibit protein synthesis by preventing the formation of the initiation complex between the 30S and 50S subunits of the ribosome.
Linezolid is a type of oxazolidinone, a relatively newer class of antibiotics that are active against multidrug-resistant staphylococci, streptococci, and enterococci. Although many antimicrobial agents affect or disrupt protein synthesis in bacteria, linezolid is unique in that it disrupts protein synthesis at its origin rather than later in the cascade. It achieves this by binding to the
50S subunit of the bacterial ribosome, preventing the formation of the initiation complex.
Swaney et al. performed a study to investigate the mechanism of action of linezolid. They found that linezolid inhibits the formation of the initiation complex in bacterial translation systems by preventing the formation of the N- formylmethionyl-tRNA-ribosome-mRNA ternary complex.
Thompson et al. performed a study on the efficacy of various antibiotics in treating periprosthetic joint infections (PJI). They administered oral linezolid with or without oral rifampin, intravenous vancomycin with oral rifampin, intravenous daptomycin or ceftaroline with or without oral rifampin, oral doxycycline, or sham treatment at human- exposure doses for 6 weeks in a mouse model of PJI. They found that oral-only linezolid-rifampin and all intravenous antibiotic-rifampin combinations resulted in no recoverable bacteria and minimized reactive bone changes. Additionally, although oral linezolid was found to be the most effective monotherapy, all oral and intravenous antibiotic monotherapies failed to clear infection or prevent reactive bone changes.
They concluded that the oral-only linezolid-rifampin option might reduce venous access complications and health-care costs.
Illustration A is a diagram depicting the mechanism of action of various antibiotics.
Incorrect Answers:
50S subunit of the bacterial ribosome, preventing protein chain elongation by inhibiting peptidyl transferase activity of the ribosome.
elongation by blocking aminoacyl translocation.
Failure of effective communication in the surgical setting has been associated with what?
Unfractionated heparin works in the coagulation cascade by promoting the ability of antithrombin III to inhibit factors IIa, III, Xa.
Heparin works by binding to and enhancing the ability of antithrombin III to inhibit factors IIa, III, Xa. It is metabolized by the liver. The risks associated with the use of unfractionated heparin include bleeding and heparin induced thrombocytopenia (HIT). The reversal agent is protamine sulfate.
Agnelli et al. reviewed direct thrombin inhibitors for the prevention of VTE after major orthopaedic surgery. They reported widespread use, however, limitations in the use of unfractionated heparin and low-molecular-weight heparins. They highlighted that direct thrombin inhibitors (Ximelagatran) inactivate thrombin without requiring any plasma cofactor, inhibit both free
and fibrin-bound thrombin, and do not appreciably bind to plasma proteins. They concluded that the features of rapid absorption, conversion, bioavailability, low variability, dose-time, food independency, and the predictable anticoagulant activity make direct thrombin inhibitors an attractive antithrombotic agent especially for prolonged out-of hospital prophylaxis.
Kwong et al. reviewed the efficacy and safety of fondaparinux, a selective factor Xa inhibitor and reported its efficacy and safety in 4 phase III clinical trials. They reported fondaparinux usage resulted in an overall 55% decrease in the risk of venous thromboembolism (VTE) relative to the low-molecular- weight heparin enoxaparin without increasing the incidence of clinically relevant bleeding, which was similarly low for both agents. They concluded
that the superior efficacy of fondaparinux relative to enoxaparin is the result of its unique mechanism of action, clinical pharmacology.
McLynn et al. investigated the risk factors and chemoprophylaxis for VTE in elective spine surgery. They reported that independent risk factors for VTE included greater age, male gender, increasing body mass index, dependent functional status, lumbar spine surgery, longer operative time, perioperative blood transfusion, longer length of stay, and other postoperative
complications. The majority of patients received unfractioned heparin and they observed this did not significantly influence the rate of VTE, but was associated with a significant increase in hematoma requiring a return to the operating room. They concluded that there is insufficient evidence to support the routine use of chemoprophylaxis in low-risk patients, and recommended full consideration of risks and benefits after elective spine surgery.
Figure A depicts the coagulation cascade, with the factor circled in red (IIa) being the target of unfractionated heparin, through its effect on antithrombin III.
Incorrect Answers:
Which of the following antibiotics acts to inhibit protein synthesis by preventing the formation of the initiation complex between the 30S and 50S subunits of the ribosome?
Acetaminophen inhibits prostaglandin E2 production through its effect on interleukin-1 beta. It exerts its effects on the central nervous system.
Multimodal pain management has become an increasingly important consideration in total joint arthroplasty recovery, namely in regard to minimizing opioid requirements while optimizing pain control and patient satisfaction. Given the negative side effects and increasing scrutiny on narcotic use, modalities that help to decrease post-operative narcotic requirements have become a major focus and include nonsteroidal anti- inflammatories, selective COX-2 inhibitors, gabapentinoids, local anesthetic blocks, and acetaminophen. Acetaminophen acts directly the central nervous system, providing both pain relief and antipyretic effects. It does so by inhibiting prostaglandin E2 production through the blockade of interleukin-1 beta.
Jinnah et al. performed a comparison of two multimodal pain regimens used for postoperative pain control in total joint arthroplasty patients. They hypothesized that using a multimodal pain protocol focusing on periarticular injections including liposomal bupivacaine would have improved results when compared with a parenteral opioid- based regimen. They found a decrease in length of stay and rate of discharge to skilled nursing facilities with the implementation of a novel multimodal protocol. They concluded that a multimodal approach inclusive of periarticular injection can lead to a reduced
length of stay.
Politi et al. performed a prospective randomized trial comparing the use of intravenous versus oral acetaminophen in total joint arthroplasty. They found that IV acetaminophen did not provide a significant difference in pain relief except within the first 0-4 hours. They concluded that IV acetaminophen does not provide a significant benefit when compared to the oral form, which is also less expensive.
Incorrect Answers:
Which of the following agents results in blood anticoagulation by exerting inhibitory effects on the factor circled in the color red in Figure A?
Based on the stress-strain curve in Figure A, ceramic has the highest modulus of elasticity.
Young's modulus is a measure of the stiffness (ability to resist deformation) of a material in the elastic zone that is calculated by measuring the slope of the stress-strain curve in the elastic zone. A higher modulus of elasticity indicates a stiffer material. Relative values of Young's modulus include: (1) ceramic, (2) alloy, (3) stainless steel, (4) titanium, (5)
cortical bone, (6) matrix polymers, (7) PMMA, (8) polyethylene, (9) cancellous bone, (10) tendon/ligaments, and (11) cartilage.
Lang et al. published a review on the use of ceramics in total hip replacement. They report that properties of ceramic which make it particularly attractive for this application include its hardness, high compression strength, and excellent wettability. However, its low fracture toughness and linear elastic behavior make it prone to breakage under stress.
Figure A is a stress-strain curve, the slope of which is used to determine Young's modulus.
Incorrect Answers:
Which of the following medications work by inhibiting prostaglandin E2 production through interleukin-1 beta?
A power analysis determines the minimum number of patients needed in a study to show a clinically significant difference. It should be performed before starting the study.
Power is the probability of finding a significant association if one truly exists. It is defined as 1 minus the probability of a type 2 error (beta) and is generally set to 80% meaning that we are willing to accept a 20% chance of a type 2 error. A power analysis will determine the minimum number of patients that shows a clinically significant difference. The minimum number of patients should be determined prior to initiating a study. Calculation of power after a study has been completed is controversial and discouraged.
Vavken et al. performed a review on the management of confounding in controlled orthopaedic trials. They report that confounding occurs when the effect of exposure of an outcome is distorted by a confounding factor and will lead to spurious effect estimates in clinical studies. They performed a cross- sectional study of a sample of controlled trials reported in the orthopaedic literature in 2006. They conclude that only 30 studies reported that the had a power analysis performed.
Kocher et al. performed a review of clinical epidemiology and biostatistics as a primer for orthopedic surgeons. They report that a power analysis should be performed prior to initiating the study. This will ensure the study is appropriately powered and decrease the effects of chance. They conclude that when a study determines no significant effect the power of the study should be reported.
Incorrect Answers:
Based on the stress-strain curve in Figure A, which of the following materials has the highest modulus of elasticity?
The World Health Organization (WHO) defines osteopenia as a bone mineral density (BMD) that is between 1 and 2.5 standard deviations below young normal (T-score of - 1 to -2.5).
The WHO defines osteopenia as decreased BMD without fracture risk. Osteopenia is defined as a T-score of 1 to 2.5 standard deviations below young normals (-1 to -2.5), while osteoporosis is defined as a T-score of more than

Question 24:

Which of the following statements is true regarding the superomedial fragment of an intra-articular calcaneus fracture?

Options:

Tibialis posterior tendon runs within its groove
Fragment typically does not move due to its attachment to the talus
Fragment typically does not move due to its attachment to the navicular
Fragment typically displaces superior and laterally
Fragment typically displaces superior and medially

Correct Answer: Tibialis posterior tendon runs within its groove

Explanation:

Question 25:

Options:

external fixation with a circular frame.
open reduction and internal fixation with screws.
closed reduction and percutaneous pinning.
closed reduction and cast immobilization.
amputation.

Correct Answer: open reduction and internal fixation with screws.

Explanation:

Question 26:

Options:

Chronic deep infection
Heterotopic bone
Femoral loosening
Parkinsonism
Acetabular loosening

Correct Answer: Femoral loosening

Explanation:

DISCUSSION: The radiographs reveal both cement debonding at the lateral shoulder of the prosthesis and a cement mantle fracture. Both of these indicate a loose femoral component. The radiographs show a stress fracture with reactive bone on the lateral femoral cortex in conjunction with the cement mantle fracture. The acetabular component shows no evidence of loosening. Heterotopic bone usually is not a source of pain when it is Brooker grade I, as in this case. Parkinsonism generally is not associated with hip pain.
REFERENCES: Harris WH, McCarthy JC, O’Neill DA: Femoral component loosening using contemporary techniques of femoral cement fixation. J Bone Joint Surg Am 1982;64:1063-1067.
Callaghan JJ, Rosenberg AG, Rubash H (eds): The Adult Hip. Philadelphia, PA, Lippincott-Raven, 1998, pp 960, 1228-1229.
Maloney WJ, Schmalzreid T, Harris WH: Analysis of long-term cemented total hip arthroplasty retrievals. Clin Orthop Relat Res 2002;405:70-78.

Question 27:

Options:

Iliotibial band bursectomy
Z-lengthening of the iliotibial band
Partial excision of the iliotibial band
Home stretching program and cross training

Correct Answer: Home stretching program and cross training

Explanation:

Question 28:

Options:

8 mm
10 mm
12 mm
14 mm
16 mm

Correct Answer: 14 mm

Explanation:

DISCUSSION: The posterior atlanto-dens interval represents the space available for the spinal cord and a distance of less than 14 mm is predictive of neurologic progression, thus warranting consideration for fusion, even in the absence of symptoms.
REFERENCE: Boden SD, Dodge LD, Bohlman HH, et al: Rheumatoid arthritis of the cervical spine: A long-term analysis with predictors of paralysis and recovery. J Bone Joint Surg Am 1993;75:1282-1297.

Question 29:

What is the most likely cause of recurrent symptoms following excision of a third web space neuroma?

Options:

Traumatic neuroma tethered by plantar neural branches
Regeneration of the transverse intermetatarsal ligament
Development of an intermetatarsal synovial cyst
Complex regional pain syndrome
Metatarsophalangeal joint synovitis

Correct Answer: Traumatic neuroma tethered by plantar neural branches

Explanation:

Question 30:

The iliopectineal fascia runs between which of the following structures?

Options:

Iliopsoas muscle and the iliac vessels/femoral nerve
Lateral femoral cutaneous nerve and the iliac vessels
Iliopsoas muscle/femoral nerve and the iliac vessels
Iliac wing and the iliopsoas muscle
Pubic symphysis and the iliac vessels

Correct Answer: Iliopsoas muscle/femoral nerve and the iliac vessels

Explanation:

DISCUSSION: The sheath of the psoas muscle or the iliopectineal fascia separates the more lateral iliopsoas muscle and the femoral nerve from the more medially located iliac vessels. This fascia has to be taken down to enter the true pelvis.
REFERENCES: Masquelet AC, McCullough CJ, Tubiana R: An Atlas of Surgical Exposures of the Lower Extremity. Philadelphia, PA, JB Lippincott, 1993.
Letournel E, Judet R: Fractures of the Acetabulum, ed 2. Berlin, Germany, Springer Verlag, 1993.
Matta J: Surgical treatment of acetabular fractures, in Browner BD, Jupiter JB, Levine AM, et al (eds): Skeletal Trauma, ed 3. Philadelphia, PA, WB Saunders, 2003, vol 1, pp 1109-1149.

Question 31:

What muscle attaches to the site shown by the arrow in Figure 2?

Options:

Teres minor
Teres major
Latissimus dorsi
Pectoralis major
Pectoralis minor

Correct Answer: Latissimus dorsi

Explanation:

Question 32:

A 55-year-old man underwent cementless total hip arthroplasty for advanced painful osteoarthritis of the hip 2 years ago. The follow-up radiograph shown in Figure 30 shows

Options:

spot welds and calcar atrophy.
subsidence.
distal cortical hypertrophy.
distal pedestal formation.
complete lucent line around the stem.

Correct Answer: spot welds and calcar atrophy.

Explanation:

Question 33:

Options:

unrecognized injury to the recurrent motor branch.
neuropraxia of the proper palmar digital nerve.
new-onset stenosing flexor tenosynovitis.
injury to the flexor digitorum profundus to the index finger.

Correct Answer: neuropraxia of the proper palmar digital nerve.

Explanation:

EXPLANATION:
Complications after carpal tunnel release are relatively uncommon. The clinical picture described above is most consistent with lumbrical muscle weakness secondary to neuropraxia of the proper palmar digital nerve to the index finger supplying motor innervation to that muscle. The recurrent motor branch of the median nerve innervates the thenar musculature and would not present as index finger weakness. A new onset of trigger finger may result from a loss of the pulley effect of the transverse carpal ligament, postoperative tendon inflammation, or previously unrecognized flexor tendon triggering. Flexor digitorum profundus to the index finger lies deep within the carpal tunnel, making its injury unlikely. If
it were injured, the result would not be weakness of interphalangeal joint extension.

Question 34:

Figures 71a and 71b/ are the MR images of a 65-year-old man who dislocated his shoulder. What is his most likely chief symptom?

Options:

Numbness in the anterior aspect of his shoulder
Recurrent instability
Difficulty raising his arm
Biceps muscle deformity

Correct Answer: Difficulty raising his arm

Explanation:

DISCUSSION
This patient has a massive rotator cuff tear resulting in disruption of the transverse force couple between the subscapularis anteriorly and the infraspinatus and teres minor posteriorly. These muscles provide dynamic shoulder stability throughout active elevation. Loss of the force couple produces a pathologic increase in translation of the humeral head and decreased active abduction and external rotation, which results in difficulty raising an arm. The most common neurologic deficit after shoulder dislocation is isolated injury to the axillary nerve that supplies sensation to the lateral aspect of the shoulder, not the anterior aspect. Recurrent instability is uncommon unless there is a labral tear or massive subscapularis tear. The biceps muscle is not viewed in the MR images, and a complete proximal biceps tendon rupture would be uncommon in the setting of an anterior shoulder dislocation.
CLINICAL SITUATION FOR QUESTIONS 72 THROUGH 75
Figures 72a through 72e are the MR images of a 12-year-old boy with left lateral-sided knee pain following a football injury. He has a several-year history of recurrent knee pain that improves with rest. An examination reveals a moderate effusion. Range of motion is 0 degrees
to 90 degrees and is limited by pain in deep flexion. He has tenderness to palpation along the lateral joint line, and no instability is noted.

Question 35:

Options:

Age > 60 years
> or = 2 comorbid conditions
History of tobacco use
BMI > 30 kg/m²
Using a pedicle subtraction osteotomy

Correct Answer: > or = 2 comorbid conditions

Explanation:

Question 36:

Options:

placement of the hips in wider abduction and continued use of the harness.
increased flexion of the hips and continued use of the harness.
removal of the harness and application of an Ilfeld splint.
removal of the harness and application of a von Rosen splint.
removal of the harness, followed by closed or open reduction.

Correct Answer: removal of the harness, followed by closed or open reduction.

Explanation:

Question 37:

Which ligament attaches to the bony fragment identified by the CT image arrows in Figures 42a and 42b?

Options:

Posterior tibiotalar ligament
Posterior-inferior tibiofibular ligament (PITFL)
Interosseous ligament (IOL)
Anterior-inferior tibiofibular ligament (AITFL) ?

Correct Answer: Posterior-inferior tibiofibular ligament (PITFL)

Explanation:

DISCUSSION
The distal tibiofibular syndesmosis is a ligamentous complex that consists of the AITFL, PITFL, intertransverse ligament (ITL), and IOL. The PITFL originates on the posterior inferior aspect of the tibia (Volkmann tubercle) and inserts on the lateral malleolus. The AITFL originates on the anterolateral aspect of the tibia (Chaput tubercle) and inserts on the distal anterior aspect of the fibula (Wagstaffe tubercle). The ITL is a group of fibers running transversely just inferior to the PITFL. As a group, these structures maintain the appropriate tibial plafond and talus relationship throughout physiologic range of motion.
RECOMMENDED READINGS
Carr JB. Malleolar fractures and soft tissue injuries of the ankle. In: Browner BD, Alen LM, Peter TG, Jupiter JB, et al. Skeletal Trauma. 3rd ed. Philadelphia, PA: Saunders; 2003:2309. Zalavras C, Thordarson D. Ankle syndesmotic injury. J Am Acad Orthop Surg.2007 Jun;15(6):330-9. Review. PubMed PMID: 17548882.
View
Abstract at PubMed
CLINICAL SITUATION FOR QUESTIONS 43 THROUGH 46
A 46-year-old healthy right-hand-dominant man falls and sustains the injury shown in Figures 43a and 43b.

Question 38:

Options:

Neurogenic
Hemorrhagic
Spinal
Septic
Hypovolemic

Correct Answer: Neurogenic

Explanation:

Question 39:

Options:

Repeat left hip aspiration
Initiation of a wound care consult and oral antibiotics
Irrigation and debridement with closure of the dehisced wound, performance of a liner exchange, and administration of intravenous antibiotics
Debridement of the wound, explant of the total hip, placement of a spacer, and administration of intravenous antibiotics

Correct Answer: Debridement of the wound, explant of the total hip, placement of a spacer, and administration of intravenous antibiotics

Explanation:

Question 40:

Which of the following plain radiographic views of the shoulder best reveals a Hill-Sachs lesion of the humeral head?

Options:

Lateral Y
Scapular AP
Neutral rotation AP
Internal rotation AP
External rotation AP

Correct Answer: Internal rotation AP

Explanation:

Question 41:

Options:

Spanning external fixation of the radius
Open reduction and internal fixation of the radius with free fibular flap interposition
Open reduction and internal fixation of the radius with interposed strut allograft
Open reduction and internal fixation of the radius with massive cancellous allografting
Open reduction and internal fixation of the radius with massive cancellous autografting

Correct Answer: Open reduction and internal fixation of the radius with free fibular flap interposition

Explanation:

Question 42:

Options:

increasing the force to dislocation of the femoral head.
increasing the range of motion until impingement of the neck on the liner.
decreasing the resisting moment to dislocation of the femoral head.
decreasing the range of motion until dislocation of the femoral head.
decreasing the range of motion until impingement of the neck on the liner.

Correct Answer: increasing the range of motion until impingement of the neck on the liner.

Explanation:

Question 43:

Options:

UCL repair and nighttime elbow extension splinting
UCL repair with ulnar nerve decompression in situ
Allograft UCL reconstruction with interference screws
Autograft UCL reconstruction with ulnar nerve transposition
Autograft UCL reconstruction using a docking technique

Correct Answer: Autograft UCL reconstruction with ulnar nerve transposition

Explanation:

Question 44:

Options:

Incision and drainage of the abscess
Nonsteroidal anti-inflammatory drugs, physical therapy, and a repeat MRI scan in 6 to 8 weeks
Open biopsy
Hematoma evacuation and musculotendinous repair
Primary wide resection followed by radiation therapy

Correct Answer: Nonsteroidal anti-inflammatory drugs, physical therapy, and a repeat MRI scan in 6 to 8 weeks

Explanation:

Question 45:

Options:

a short leg cast with the ankle in slight plantar flexion.
a corticosteroid injection into the retrocalcaneal bursa.
excision of the os trigonum.
excision of the superior tuberosity of the calcaneus.
ankle arthroscopy with loose body removal.

Correct Answer: excision of the os trigonum.

Explanation:

Question 46:

Options:

the addition of more aggressive physiotherapy.
observation and continued non-weight-bearing.
addition of an anteriorly directed "syndesmosis screw."
loosening the syndesmotic screws from an overtightened position.
removal of screws, re-reduction of the syndesmosis, and revision fixation.

Correct Answer: removal of screws, re-reduction of the syndesmosis, and revision fixation.

Explanation:

Question 47:

The dose of the chemotherapeutic agent doxorubicin (Adriamycin) is limited by which of the following factors?

Options:

Cardiotoxicity
Nephrotoxicity
Hepatotoxicity
Bone marrow suppression
Peripheral neuropathy

Correct Answer: Cardiotoxicity

Explanation:

Question 48:

Options:

Traction followed by reduction and pinning
In situ pinning of the left hip
In situ pinning of both hips
No weight bearing on the left side and nonsteroidal anti-inflammatory drugs
Femoral realignment osteotomy

Correct Answer: In situ pinning of both hips

Explanation:

Question 49:

Options:

An MRI scan
Muscle biopsy
Carpal tunnel diagnostic injection
Electrodiagnostic testing
Carpal tunnel view radiograph

Correct Answer: An MRI scan

Question 50:

Options:

initiation of a first-generation cephalosporin while awaiting culture results.
initiation of broad-spectrum antibiotics while awaiting culture results.
ultrasound to evaluate for fluid collection around the knee.
surgical debridement of the knee before culture results are available.
inpatient observation and no antibiotics until culture results are available.

Correct Answer: surgical debridement of the knee before culture results are available.

Explanation:

AL-Madena Copy
8 • American Academy of Orthopaedic Surgeons
DISCUSSION: Increased pain, swelling, erythema, and drainage 2 weeks removed from the primary arthroplasty are all signs of a probable infection. Erythrocyte sedimentation rate and C-reactive protein may not be helpful as they are elevated postoperatively even in the absence of infection. Even in the absence of infection, persistent wound drainage is an indication for surgical debridement to prevent subsequent infection. When a postoperative infection is easily recognized by clinical examination, there is no need to wait for a positive culture before proceeding with debridement.
REFERENCES: Weiss AP, Krackow KA: Persistent wound drainage after primary total knee arthroplasty. J Arthroplasty 1993;8:285-289.
Jaberi FM, Parvizi J, Haytmanek CT, et al: Procrastination of wound drainage and malnutrition affect the outcome of joint arthroplasty. Clin Orthop Relat Res 2008;466:1368-1371.
Insall JN, Windsor RE, Scott, WN: Surgery of the Knee, ed 2. New York, NY, Churchill Livingstone, 1993, pp 959-964.
Figure 3a Figure 3b

Question 51:

What mechanism of injury is most likely to cause a fracture of the anteromedial facet of the coronoid?

Options:

Extension and axial load
Varus and posteromedial rotation
Valgus and posteromedial rotation
Varus and posterolateral rotation
Valgus and posterolateral rotation

Correct Answer: Extension and axial load

Explanation:

The mechanism of injury in a fracture of the anteromedial facet of the coronoid is typically a varus and posteromedial rotation force on the forearm which is the opposite of a terrible triad injury. First, the lateral collateral ligament is injured and then the medial coronoid is compressed against and then under the medial trochlea.
(SBQ12TR.86) Figure A shows intraoperative radiographs of a 45-year-old patient with a left elbow injury. What would be the next most appropriate step in this patients care?
Early range of motion
Hinged elbow brace for 4 weeks
Repair lateral collateral ligament
Remove and upsize implant
Remove and downsize implant
The intraoperative images are consistent with overstuffing of the ulnohumeral joint during a radial head replacement. The most appropriate next step would be removing and downsizing the implant.
Overstuffing the radiohumeral joint by >2.5 mm can significantly alter elbow kinematics. It has also shown to lead to pain and early joint disease. The most sensitive method to assess for overstuffing of the joint is by direct visualisation intraoperatively. This can be performed by visualising the lateral aspect of the ulnohumeral joint when the radial head is resected and comparing this to when the trial radial head is reduced in place. In comparison, radiographic asymmetry of the medial ulnohumeral joint has been shown to be less sensitive. Radiographic findings of incongruity of ulnohumeral joint only occurs when significant overlengthening of the radius occurs.
Frank et al. examined the effect of radial head thickness in seven cadaver specimens. They found that incongruity of the medial ulnohumeral joint would only become apparent radiographically after overlengthening of the radius by >or=6 mm.
Doornberg et al. examined seventeen computed tomography scans of the elbow to investigate the height of the radial head relative to the lateral edge and central ridge of the coronoid process. They found that the radial head was on average only 0.9 mm more proximal than the lateral edge of the coronoid process.
Figure A shows intraoperative radiographs of a patient that has undergone a radial head arthroplasty. There is significant widening of the medial ulnohumeral joint on an AP radiograph as well as widening of the ulnohumeral joint on the lateral radiograph,
Incorrect Answers:

Question 52:

Figure 29 is the radiograph of a 30-year-old man who sustained an isolated tibial shaft fracture. What is the most common deformity with nonsurgical management?

Options:

Varus
Malrotation
Valgus
Valgus and procurvatum
Valgus and recurvatum

Correct Answer: Varus

Explanation:

Question 53:

Options:

threaded (screw-in) cup with a hydroxyapatite coating.
protrusio cage reconstruction with a cemented cup.
large cementless cup with bone grafting of defects.
small cup with a high and lateral hip center.
bulk allograft reconstruction of the defect with a cemented cup.

Correct Answer: large cementless cup with bone grafting of defects.

Explanation:

Question 54:

Which of the following imaging modalities is most accurate in locating a toothpick in the plantar arch of the foot?

Options:

Radiograph
CT
MRI
Ultrasound
Bone scan

Correct Answer: Ultrasound

Explanation:

DISCUSSION: Ultrasound is best at imaging abrupt changes in the density of adjacent tissue and therefore is best at imaging wood in the soft tissues of the foot.
REFERENCES: Mizel MS, Steinmetz ND, Trepman E: Detection of wooden foreign bodies in muscle tissue: Experimental comparison of computed tomography, magnetic resonance imaging, and ultrasonography. Foot Ankle Int 1994;15:437-443.
Jacobson JA, Powell A, Craig JG, et al: Wooden foreign bodies in soft tissue: Detection at US. Radiology 1998;206:45-48.

Question 55:

What arterial vessel is most prone to injury during posterior iliac crest bone graft harvest?

Options:

Superior gluteal
Deep circumflex iliac
Iliolumbar
Ascending branch of the lateral femoral circumflex
Fourth lumbar

Correct Answer: Superior gluteal

Explanation:

Question 56:

Options:

Decreased blood loss
Less neural retraction
Improved neuroforaminal height
Lower fusion rates

Correct Answer: Improved neuroforaminal height

Explanation:

DISCUSSION
Interbody fusion, when compared to PLF, is a predictor of more substantial blood loss. Multilevel posterior lumbar interbody fusion (PLIF) is an independent predictor of blood loss for posterior spine fusion. Some retrospective studies suggest that fusion rates are higher for transforaminal lumbar interbody fusion (TLIF) than PLF, but this finding has not been borne out in prospective studies. The main advantage of TLIF in the context of this question is restoration of neuroforaminal height, and many surgeons will consider TLIF or PLIF for that reason. The parasagittal MR image seen in Figure 9c shows neuroforaminal narrowing. The pre- and postsurgical radiographs show a difference in neuroforaminal height.
RECOMMENDED READINGS
DiPaola CP, Molinari RW. Posterior lumbar interbody fusion. J Am Acad Orthop Surg. 2008 Mar;16(3):130-9. Review. PubMed PMID: 18316711.
View Abstract at PubMed
Eismont FJ, Norton RP, Hirsch BP. Surgical management of lumbar degenerative spondylolisthesis. J Am Acad Orthop Surg. 2014 Apr;22(4):203-13. doi: 10.5435/JAAOS-22-04-203. Review. PubMed PMID: 24668350.
View Abstract at PubMed
McAfee PC, DeVine JG, Chaput CD, Prybis BG, Fedder IL, Cunningham BW, Farrell DJ, Hess SJ, Vigna FE. The indications for interbody fusion cages in the treatment of spondylolisthesis: analysis of 120 cases. Spine (Phila Pa 1976). 2005 Mar 15;30(6 Suppl):S60-5. PubMed PMID: 15767888.
View Abstract at PubMed
RESPONSES FOR QUESTIONS 10 THROUGH 14
Postoperative deep surgical site infection
Proximal junctional kyphosis
Pedicle screw cut-out
Pseudarthrosis
Sagittal imbalance
Please match the scenario described below with the most likely complication listed above.

Question 57:

Options:

disruption of the sympathetic nerves during anterior lumbar exposure.
traction on the parasympathetic nerve at the L4-5 level.
not related to the surgical dissection.
injury to the pudendal nerves in the anterior sacral region during dissection at the L5-S1 level.
sexual dysfunction secondary to retrograde ejaculation.

Correct Answer: not related to the surgical dissection.

Explanation:

Question 58:

A college football player performs bicep curls as part of his weight lifting routine. During the flexion phase of the curl, what term defines the type of muscle contraction?

Options:

Isometric
Isokinetic
Isotonic
Eccentric
Plyometric

Correct Answer: Plyometric

Explanation:

Question 59:

Options:

Partial tear of the patellar tendon
Osteochondral fracture of the femur
Anterior cruciate ligament (ACL) tear
Posterior cruciate ligament (PCL) tear
Patella fracture

Correct Answer: Posterior cruciate ligament (PCL) tear

Explanation:

Question 60:

Which of the following conditions routinely requires early surgical intervention in patients with Marfan syndrome? Review Topic

Options:

Kyphosis
Ankle instability
Protrusio acetabula
Progressive scoliosis
Pseudarthrosis of the tibia

Correct Answer: Progressive scoliosis

Explanation:

Question 61:

Options:

0 to 15 degrees
20 to 30 degrees
40 to 90 degrees
100 to 120 degrees
130 to 140 degrees

Correct Answer: 40 to 90 degrees

Explanation:

Question 62:

Options:

skeletal traction.
immediate application of a cast brace.
a retrograde supracondylar nail.
revision total knee replacement.
resection arthrodesis.

Correct Answer: a retrograde supracondylar nail.

Explanation:

Question 63:

Options:

Continued observation
Open reduction and internal fixation of the fracture
Excision of the hook of the hamate
Carpal tunnel release
Guyon’s canal release

Correct Answer: Excision of the hook of the hamate

Explanation:

Question 64:

Which of the following best describes the course of the median nerve at the elbow?

Options:

Crosses superficial to the ulnar artery, deep to the fibrous arch of the superficialis muscle, deep to the superficial head of the pronator teres muscle
Crosses superficial to the ulnar artery, deep to the fibrous arch of the superficialis muscle, superficial to the superficial head of the pronator teres muscle
Crosses deep to the ulnar artery, deep to the fibrous arch of the superficialis muscle, deep to the superficial head of the pronator teres muscle
Crosses deep to the ulnar artery, deep to the fibrous arch of the superficialis muscle, superficial to the superficial head of the pronator teres muscle
Crosses deep to the ulnar artery, superficial to the fibrous arch of the superficialis muscle, superficial to the superficial head of the pronator teres muscle

Correct Answer: Crosses superficial to the ulnar artery, deep to the fibrous arch of the superficialis muscle, deep to the superficial head of the pronator teres muscle

Explanation:

Question 65:

Options:

Distal rerouting of the biceps tendon
Glenohumeral fusion with external rotation
External rotation osteotomy of the proximal humerus
Latissimus dorsi and teres major transfer to the posterior rotator cuff
Latissimus dorsi and teres major transfer to the subscapularis

Correct Answer: Latissimus dorsi and teres major transfer to the posterior rotator cuff

Explanation:

Question 66:

What is the advantage of percutaneous pedicle screw fixation over open instrumentation and fusion for a thoracolumbar burst fracture without neurologic deficit?

Options:

Better clinical outcomes
Less blood loss
Less pseudarthrosis risk
Lower revision surgery rate

Correct Answer: Less blood loss

Explanation:

DISCUSSION
A prospective randomized study on short-segment treatment of burst fractures with and without fusion demonstrated similar outcomes at 5 years with lower blood loss in the nonfusion group. There is by definition no fusion performed with percutaneous stabilization, so patients often develop hardware failure. Some surgeons routinely remove instrumentation following percutaneous stabilization, thus revision surgery is common. Clinical outcomes are not improved compared to open methods.
RECOMMENDED READINGS
Koreckij T, Park DK, Fischgrund J. Minimally invasive spine surgery in the treatment of thoracolumbar and lumbar spine trauma. Neurosurg Focus. 2014;37(1):E11. doi: 10.3171/2014.5.FOCUS1494. Review. PubMed PMID: 24981899.
View Abstract at PubMed
Jindal N, Sankhala SS, Bachhal V. The role of fusion in the management of burst fractures of the thoracolumbar spine treated by short segment pedicle screw fixation: a prospective randomised trial. J Bone Joint Surg Br. 2012 Aug;94(8):1101-6. doi: 10.1302/0301-620X.94B8.28311. PubMed PMID: 22844053.
View Abstract at
PubMed
Dai LY, Jiang LS, Jiang SD. Posterior short-segment fixation with or without fusion for thoracolumbar burst fractures. a five to seven-year prospective randomized study. J Bone
Joint Surg Am. 2009 May;91(5):1033-41. doi: 10.2106/JBJS.H.00510. PubMed PMID:

Question 67:

Which of the following nerves is most commonly injured when obtaining a bone graft from the posterior ilium?

Options:

Lateral femoral cutaneous
Superior gluteal
Cluneal
L5 nerve root
S1 nerve root

Correct Answer: Cluneal

Explanation:

Question 68:

Options:

Lateral
Posterior
Posterolateral
Anterior
Anteromedial

Correct Answer: Lateral

Explanation:

Question 69:

What are the optimal conditions for leaving the acetabular shell in place, replacing the acetabular liner, and grafting the osteolytic defect shown in Figure 39?

Options:

Nonmodular implant
Instability
Well-designed, well-fixed modular implant
Complete radiolucency of the acetabular component
Migration of the acetabular component

Correct Answer: Well-designed, well-fixed modular implant

Explanation:

DISCUSSION: Dense pods of ingrowth into the porous coating of cementless ingrowth sockets are seen. Channels through the non-ingrown portion allow access to the trabecular bone of the ilium. Polyethylene wear debris can enter these areas through screw holes. Expansile, lytic lesions can result, which can become large without compromising implant fixation. Loosening is late and results from catastrophic loss of bone. A well-fixed acetabular component with a modular design, a well-designed locking mechanism, and a good survivorship history is a candidate for exchange of the liner and grafting of the osteolytic lesion.
REFERENCES: Ries MD: Complications in primary total hip arthroplasty: Avoidance and management. Wear. Instr Course Lect 2003;52:257-265.
Dumbleton JH, Manley MT, Edidin AA: A literature review of the association between wear rate and osteolysis in total hip arthroplasty. J Arthroplasty 2002;17:649-661.
Pelicci PM, Tria AJ Jr, Garvin KL (eds): Orthopaedic Knowledge Update: Hip and Knee Reconstruction 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2000,
pp 175-180.

Question 70:

- What is the treatment of choice for an adult who has an isolated fracture of the ulna at the junction of the distal and middle thirds, with 5 degrees apex dorsal angulation and 25% displacement?

Options:

Intramedullary rodding
Functional bracing
Closed reduction and a long arm cast
Closed reduction and application of an external fixator
Open reduction and internal fixation with a dorsal plate

Correct Answer: Functional bracing

Explanation:

Question 71:

Figures 28a through 28d show the radiographs and MRI scans of a 20-year-old basketball player who sustained an inversion injury to his right ankle. Management should consist of

Options:

open reduction and internal fixation.
a short leg cast for 6 weeks.
ankle arthroscopy, removal of the fragment, and drilling of the base of the lesion.
ankle arthroscopy and internal fixation.
functional ankle rehabilitation that emphasizes range of motion, peroneal strengthening, and proprioceptive training.

Correct Answer: ankle arthroscopy, removal of the fragment, and drilling of the base of the lesion.

Explanation:

Question 72:

Options:

In all suprasyndesmotic fibular fractures
In all transsyndesmotic fibular fractures
When there is increased medial clear space with external rotation stress
If the deltoid ligament is ruptured
If the posterior malleolus is fractured

Correct Answer: When there is increased medial clear space with external rotation stress

Explanation:

Question 73:

The injection shown in Figures 1a and 1b would most benefit a patient who reports which of the following symptoms?

Options:

Dorsal foot pain extending into the great toe
Foot pain extending along the lateral border of the foot
Pain extending into the foot in a stocking distribution
Anterior thigh and shin pain ending at the ankle
Lateral foot paresthesias

Correct Answer: Dorsal foot pain extending into the great toe

Explanation:

DISCUSSION: The images demonstrate a L5 selective root block as it exits the L5-S1 foramen. This root block best helps relieve pain or paresthesias in the L5 distribution, which is the dorsal first web space and the great toe. The lateral foot is an S1 distribution and would need to be blocked through the posterior first sacral foramen. The anterior shin and thigh represent the
L4 root which exits a level above this at the L4-5 foramen. A stocking distribution is nonanatomic and not indicative of a specific root.
REFERENCES: Magee D: Principles and concepts, in Orthopaedic Physical Assessment, ed 3. Philadelphia, PA, WB Saunders, 1997, pp 1-18.
Aeschbach A, Mekhail NA: Common nerve blocks in chronic pain management. Anesthesiol Clin North Am 2000;18:429-459.

Question 74:

What is the most appropriate treatment?

Options:

Arthroscopic washout
CT scan
Observation
Aspiration

Correct Answer: Observation

Explanation:

Question 75:

Options:

Giant cell tumor
Chondrosarcoma
Osteosarcoma
Infection
Paget’s disease

Correct Answer: Chondrosarcoma

Explanation:

Question 76:

Options:

Superior approach with trochanteric slide
Direct anterior approach with a chevron modification of the standard greater trochanteric osteotomy
Lateral approach with a partial greater trochanter osteotomy
Posterolateral approach with an extended trochanteric osteotomy Submit Answer

Correct Answer: Posterolateral approach with an extended trochanteric osteotomy Submit Answer

Explanation:

Question 77:

Options:

Repeat left hip aspiration
Initiation of a wound care consult and oral antibiotics
Irrigation and debridement with closure of the dehisced wound, performance of a liner exchange, and administration of intravenous antibiotics
Debridement of the wound, explant of the total hip, placement of a spacer, and administration of intravenous antibiotics

Correct Answer: Debridement of the wound, explant of the total hip, placement of a spacer, and administration of intravenous antibiotics

Explanation:

Question 78:

Options:

Ankle-foot orthosis with anterior shell
Vascularized fibular graft
Intramedullary nailing of the left tibia
Amputation
Physical therapy

Correct Answer: Ankle-foot orthosis with anterior shell

Explanation:

Question 79:

Options:

Subtrochanteric osteotomy with femoral shortening
An offset femoral component
A lateralized liner
Extended trochanteric osteotomy

Correct Answer: Subtrochanteric osteotomy with femoral shortening

Explanation:

Question 80:

In infantile idiopathic scoliosis, which of the following factors suggests progression?

Options:

Age at presentation
Rib overlap of the apical vertebra
Rib vertebral angle difference of greater then 10 degrees
Male gender
Family history

Correct Answer: Rib overlap of the apical vertebra

Explanation:

Question 81:

Options:

Arthroscopic debridement
Arthroscopic rotator cuff repair
Hemiarthroplasty with rotator cuff repair
Total shoulder arthroplasty
Reverse shoulder arthroplasty

Correct Answer: Reverse shoulder arthroplasty

Explanation:

Question 82:

Options:

Manipulation under anesthesia
Left total knee arthroplasty (TKA)
Stem cell injection
Unicompartmental knee arthroplasty in the lateral compartment The patient has a valgus deformity and has developed stiffness in both flexion and extension. Given the progressive loss of motion, progression to TKA is indicated. Manipulation under anesthesia would not be efficacious to prevent the progressive loss of motion without correcting the underlying mechanical issues. The patient has global pain; and therefore, unicompartmental knee arthroplasty is not ideal. Stem cell injection in this setting has not been proven.

Correct Answer: Left total knee arthroplasty (TKA)

Explanation:

Question 83:

Options:

Posterior decompression
Posterior interbody arthrodesis
Posterior decompression and in situ arthrodesis
Posterior decompression and instrumented arthrodesis
Anterior and posterior arthrodesis

Correct Answer: Posterior decompression and instrumented arthrodesis

Explanation:

Question 84:

Options:

Deep periprosthetic joint infection
Deep vein thrombosis
Hemarthrosis
Extensor mechanism disruption

Correct Answer: Hemarthrosis

Explanation:

Question 85:

What is the most likely contributory factor to this patient's problem?

Options:

Throwing curveballs
Year-round throwing
Poor calcium intake
Shoulder laxity

Correct Answer: Year-round throwing

Explanation:

Question 86:

Options:

percutaneous bilateral adductor tenotomy.
oral baclofen.
phenol injection into the obturator nerve.
open adductor tenotomy with neurectomy of the anterior branch of the obturator nerve.
open adductor tenotomy with release of the iliopsoas and bilateral proximal femoral varus derotation osteotomy.

Correct Answer: open adductor tenotomy with release of the iliopsoas and bilateral proximal femoral varus derotation osteotomy.

Explanation:

DISCUSSION: The natural history of the patient’s hips, if left untreated, is gradual progression to dislocation. To prevent future pain, prevention of dislocation is often helpful. The patient is too old for soft-tissue releases alone. Therefore, the treatment of choice is medial release of both hips to obtain 45 degrees or better of hip abduction in conjunction with psoas tenotomy and bilateral femoral varus osteotomies.
REFERENCES: Presedo A, Oh CW, Dabney KY, et al: Soft-tissue releases to treat spastic hip subluxation in children with cerebral palsy. J Bone Joint Surg Am 2005;87:832-841.
Miller F, Bagg MR: Age and migration percentage as risk factors for progression in spastic hip disease. Dev Med Child Neurol 1995;37:449-455.

Question 87:

Options:

Diagnostic arthroscopy
MRI-arthrography
Stress radiographs
CT
Weighted radiographs of the arm

Correct Answer: MRI-arthrography

Explanation:

Question 88:

Options:

Costotransversectomy
Laminectomy
Transpedicular
Lateral extracavitary
Transthoracic

Correct Answer: Laminectomy

Explanation:

Question 89:

A patient reports pain in the hip with functional positioning. With the patient supine, pain in which of the following positions would be typical for femoral acetabular impingement?

Options:

Hip is internally rotated, passively flexed to 90 degrees, and adducted
Hip is internally rotated, passively flexed to 90 degrees, and abducted
Hip is externally rotated, maximally flexed to 90 degrees, and adducted
Hip is externally rotated, passively flexed to 90 degrees, and abducted
Hip is externally rotated, maximally flexed, and abducted

Correct Answer: Hip is internally rotated, passively flexed to 90 degrees, and adducted

Explanation:

DISCUSSION: Patients with dysplasia often have a hypertrophic labrum. Abnormal contact between the femoral neck and the acetabular rim leads to labral injury, especially in the anterior-superior acetabular zone. Typically, young patients with the condition report pain with activity or long periods of sitting or driving. The hips often have limited motion, in particular in internal rotation and flexion. Forceful adduction with the maneuver causes pain.
REFERENCES: Vaccaro AR (ed): Orthopaedic Knowledge Update 8. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2005, pp 411-424.
Beck M, Leunig M, Parvizi J, et al: Anterior femoroacetabular impingement: Part II. Midterm results of surgical treatment. Clin Orthop 2004;418:67-73.
McCarthy JC, Noble PC, Schuck MR, et al: The role of labral lesions to development of early degenerative hip disease. Clin Orthop 2001;393:25-37.

Question 90:

A 72-year-old woman who fell on her right shoulder while using a treadmill is now unable to elevate her right arm. An MRI scan is shown in Figure 7. What is the most likely diagnosis?

Options:

Axillary nerve injury
Anterior dislocation
Extension of a chronic large rotator cuff tear
Suprascapular nerve entrapment from a ganglion cyst
Greater tuberosity avulsion

Correct Answer: Extension of a chronic large rotator cuff tear

Explanation:

Question 91:

Options:

Equatorial contact should exceed polar contact.
Polar contact should exceed equatorial contact.
Polar and equatorial contact should be equal by exactly duplicating radii.
The “bedding in” process makes consideration of polar equatorial contact unimportant.
The stiffness of metal-on-metal articulations makes consideration of polar equatorial contact unimportant.

Correct Answer: Polar contact should exceed equatorial contact.

Explanation:

Question 92:

What joint always remains uninvolved in all stages of scapholunate advanced collapse (SLAC) deformity of the wrist?

Options:

Distal radioscaphoid
Proximal radioscaphoid
Radiolunate
Scaphocapitate
Capitolunate

Correct Answer: Radiolunate

Explanation:

Question 93:

The implant shown in Figures 47a and 47b is introduced submuscularly employing a minimally invasive technique. A percutaneous method of screw insertion is used distally. What nerve is most at risk?

Options:

Sural
Saphenous
Superficial peroneal
Deep peroneal
Posterior tibial

Correct Answer: Superficial peroneal

Explanation:

Question 94:

Which of the following is considered a limitation of the Short Form 36 (SF-36) general health status instrument when applied to musculoskeletal conditions?

Options:

Potential for "ceiling" and "floor" effects
Normative population data have not been attained
Patient's perspective is marginalized or ignored
Must be performed on-site by investigator
Better upper than lower extremity application

Correct Answer: Potential for "ceiling" and "floor" effects

Explanation:

Question 95:

Options:

Strong
Moderate
Limited
Inconclusive

Correct Answer: Moderate

Explanation:

Question 96:

Options:

Reamed intramedullary nail
Unreamed intramedullary nail
Percutaneous plate fixation
Skeletal traction
External fixation

Correct Answer: External fixation

Explanation:

Question 97:

Options:

Glenoid bone loss of 10%
Capsular attenuation from prior thermal capsulorraphy
Anterior labral periosteal sleeve avulsion (ALSPA ) lesion
Glenoid labral articular defect (GLAD) lesion
Combined Superior Labrum from Anterior to Posterior tear (SLAP) and recurrent Bankart lesion

Correct Answer: Glenoid bone loss of 10%

Explanation:

Question 98:

At the time of arthroscopy, a 9-year-old boy was found to have a Watanabe type II discoid lateral meniscus. What is the most appropriate treatment? Review Topic

Options:

Saucerization of the meniscus only
Saucerization and stabilization of the meniscus
Stabilization of the meniscus only
Complete menisectomy

Correct Answer: Saucerization of the meniscus only

Explanation:

Question 99:

What is the most common malignant bone tumor seen in patients with multiple hereditary exostosis?

Options:

Dedifferentiated chondrosarcoma
Mesenchymal chondrosarcoma
Secondary chondrosarcoma
Clear cell chondrosarcoma
Periosteal osteosarcoma

Correct Answer: Secondary chondrosarcoma

Explanation:

Question 100:

Options:

Long standing anterior-posterior radiograph of the hip-knee-ankle
Axial CT views from the supracondylar distal femur to the proximal tibia below the tibial tubercle
Fluoroscopic stress views to demonstrate the position of subluxation
Bone scan
MRI scan

Correct Answer: Axial CT views from the supracondylar distal femur to the proximal tibia below the tibial tubercle

Orthopedic Surgery Board Review MCQs: Arthroplasty, Ligament & Spine | Part 149

Orthopedic Board Review MCQs: Lower Extremity Trauma & Arthroplasty | Part 155

Key Takeaway

About This Board Review Set

How to Use the Interactive Quiz

Topics Covered in Part 155

Sample Questions from This Set

Why Active MCQ Practice Works

Chapter Index