Orthopedic Surgery Mock Exam - Set D14A91

- Abnormal femoral head-neck junction offset

Quadriceps-sparing approaches for TKA have shown higher risk of implant malalignment compared with the traditional medial parapatellar approach. No consistent clinically significant benefit to patient-reported outcomes has been demonstrated with quadriceps-sparing TKA, nor is there a significant improvement in postoperative quadriceps strength. Longer surgical and tourniquet times have been observed with “minimally invasive” approaches.

The piano key sign is a demonstration of instability at the DRUJ, typically seen after healing from a distal radius fracture with an associated ulnar styloid fracture (as in this case) or other wrist injury. The hand is pushed down against a table top, and the distal radius translates dorsally (with the distal ulna apparently moving volarly). In fact, the distal radius is the mobile segment, while the distal ulna is fixed in space. Treatment involves repair or reconstruction of the foveal insertion of the triangular fibrocartilage complex (TFCC) and distal radioulnar ligaments. This type of instability is also common in malunions of the distal radius or distal one-third of the radial shaft (Galeazzi-type fractures). In malunions, DRUJ instability can be treated with a corrective osteotomy of the distal radius to restore the anatomic relationship between the distal ulna and the distal radius at the DRUJ. Radiocarpal and midcarpal instability do not involve the DRUJ. Disruption of the interosseous membrane (in isolation, with intact distal radioulnar ligaments and an intact TFCC) does not lead to translational instability of the DRUJ. Although hypermobility syndrome may lead to ligamentous laxity, it does not lead to unilateral DRUJ instability.

There are a set of disorders with a sex-linked inheritance pattern that are most likely caused by a point mutation in the short stature homeobox gene. These disorders include:
Turnerâs syndrome
Langer mesomelic dysplasia
Leri-Weill dyschondrosteosis
The other responses refer to common disorders with well-documented genetic abnormalities:
Achondroplasia: FGFR3
Diastrophic dysplasia: DTDST (sulfate transporter gene) C leidocranial dysplasia: C BFA1
Multiple epiphyseal dysplasia: C OMP
C orrect Answer: Turnerâs syndrome

A Weber type B ankle fracture occurs with a supination external rotation mechanism of injury. The fibula generally fails with a spiral fracture pattern. The lag screws provide compression, and the plate acts to neutralize rotational and angular bending forces. A buttress plate resists vertical shear forces. A tension band is used over areas that may fail in tension, such as an olecranon fracture. Compression is provided by the lag screws, and distraction is again resisted by the lag screws.
REFERENCE: Mazzoca AD: Principles of internal fixation, in Browner BD, Jupiter JB, Levine AM, et al (eds): Skeletal Trauma, ed 2. Philadelphia, PA, WB Saunders, 1998, pp 308-309.

The imaging shows an infiltrative soft-tissue mass. Histology demonstrates a bland spindle-cell lesion without nuclear atypia consistent with desmoid tumor. Extraskeletal Ewing sarcoma would be expected to reveal more surrounding edema and small, round blue cells on histology. Synovial sarcoma would have a biphasic appearance consisting of spindle cells and plump epithelial cells arranged in glands or cords. Epithelial membrane antigen is often found in synovial sarcoma. Studies have demonstrated that desmoid tumors express estrogen receptors. As a result, tamoxifen has been 1 of the modalities used to treat this lesion.
RECOMMENDED READINGS
85. [Robbin MR, Murphey MD, Temple HT, Kransdorf MJ, Choi JJ. Imaging of musculoskeletal fibromatosis. Radiographics. 2001 May-Jun;21(3):585-600. Review. ](http://www.ncbi.nlm.nih.gov/pubmed/11353108)[View Abstract at PubMed](http://www.ncbi.nlm.nih.gov/pubmed/11353108)
86. [Deyrup AT, Tretiakova M, Montag AG. Estrogen receptor-beta expression in extraabdominal fibromatoses: an analysis of 40 cases. Cancer. 2006 Jan 1;106(1):208-13. ](http://www.ncbi.nlm.nih.gov/pubmed/16333857)[View Abstract at PubMed](http://www.ncbi.nlm.nih.gov/pubmed/16333857)
87. Molloy AP, Hutchinson B, O'Toole GC. Extra-abdominal desmoid tumours: a review of the literature. Sarcoma. 2012;2012:578052. doi: 10.1155/2012/578052. Epub 2012 Aug 16. PubMed PMID:
[22966217/. ](http://www.ncbi.nlm.nih.gov/pubmed/22966217)[View Abstract at PubMed](http://www.ncbi.nlm.nih.gov/pubmed/22966217)
88. [Hosalkar HS, Torbert JT, Fox EJ, Delaney TF, Aboulafia AJ, Lackman RD. Musculoskeletal desmoid tumors. J Am Acad Orthop Surg. 2008 Apr;16(4):188-98. Review. ](http://www.ncbi.nlm.nih.gov/pubmed/18390481)[View Abstract at PubMed](http://www.ncbi.nlm.nih.gov/pubmed/18390481)

Minor degrees of displacement not apparent on plain radiographs lead to significant decrease in the contact area of the second tarsometatarsal joint. Dorsolateral subluxation of the second tarsometatarsal joint suffers a loss of contact area more severely than pure dorsal or lateral subluxation. Just 3 mm of dorsolateral subluxation causes a 38% loss of contact area.

The patient has not undergone a trial of foot-specific patient education and accommodative/therapeutic shoe wear. He must use therapeutic shoe wear at all times, as even the occasional use of pressure-concentrating shoe wear has a high likelihood of leading to the development of a diabetic foot ulcer.
REFERENCES: Pinzur MS, Kernan-Schroeder D, Emmanuele NV, et al: Development of a nurse-provided health system strategy for diabetic foot care. Foot Ank Int 2001;22:744-746.
Pinzur MS, Shields N, Goelitz B, et al: American Orthopaedic Foot & Ankle Society shoe survey of diabetic patients. Foot & Ankle Int 1999;20:703-707.
Reiber GE, Smith DG, Wallace CM, et al: Effect of therapeutic footwear on foot reulceration in patients with diabetes: A randomized controlled trial. JAMA 2002;287:2552-2558.

Spontaneous partial reduction will occur when the patient becomes upright, and there is good remodeling potential due to growth.
C losed reduction and abduction cast is not necessary because of the patientâs age, remodeling potential, and range of motion available in the joint.
A formal attempt at closed reduction is not necessary because there is no way of holding it without internal fixation. This process will occur naturally to a large degree when the patient becomes upright.
Open reduction and percutaneous pin fixation poses a risk of pin tract infection because of the large amount of muscle traversed. This procedure is not necessary because of the good results with conservative treatment.

The calcaneus fracture is associated with subluxation of the subtalar joint, giving the appearance of injury to the talus and calcaneus. The true extent of the injury cannot be determined without a computed tomography scan; however, the question is not as to the outcome of treatment, but the ability to return this patient to his occupation. At 4 weeks following injury, while open reduction internal fixation of the fracture is possible, anatomic reduction may be difficult. The most likely means of returning this patient to work is with early arthrodesis, which should be combined with an open reduction internal fixation of the calcaneus.

5/. pelvic external fixation followed by sacroiliac screws
This patient sustained an open-book pelvic fracture with a pubic symphysis diastasis of less than 2.5cm. From the Young and Burgess classification, he has anteroposterior compression (AP) type 1 injury. Treatment of this is protected weight-bearing and symptomatic treatment. Stress examination can be utilized in order to ensure that the injury is, in fact, a APC-1 injury, and not a more severe posterior injury that would require operative intervention.

Complications of thermal capsule shrinkage or accelerated rehabilitation include capsule ablation. Since the original surgery did not include labral reattachment, findings of a Bankart lesion or a glenoid fracture from a nontraumatic injury are unlikely. Subscapularis detachment or biceps subluxation is a postoperative complication of open repairs. Failure of early postoperative instability treatment should not produce loose bodies.
REFERENCES: Abrams JS: Thermal capsulorrhaphy for instability of the shoulder: Concerns and applications of the heat probe. Instr Course Lect 2001;50:29-36.
Hecht P, Hayashi K, Lu Y, et al: Monopolar radiofrequency energy effects on joint capsular tissue: Potential treatment for joint instability. An in vivo mechanical, morphological, and biochemical study using an ovine model. Am J Sports Med 1999;27:761-771.

Type II, IX, and XI collagen forms a fibrillar network that gives cartilage its form and tensile stiffness and strength. Type VI collagen forms part of the matrix immediately surrounding chondrocytes and may help attach the cells attach to the matrix macromolecular framework.

The tenosynovium excised at the time of a carpal tunnel release for idiopathic carpal tunnel syndrome rarely shows signs of acute or chronic inflammation. Fibrosis, edema, and vascular sclerosis are the most common histologic findings. A tenosynovectomy with a carpal tunnel release usually is not necessary in the treatment of idiopathic carpal tunnel syndrome.
REFERENCES: Shum C, Parisien M, Strauch RJ, et al: The role of flexor tenosynovectomy in the operative treatment of carpal tunnel syndrome. J Bone Joint Surg Am 2002;84:221-225.
Fuchs PC, Nathan PA, Myers LD: Synovial histology in carpal tunnel syndrome. J Hand Surg Am 1991;16:753-758.
Kerr CD, Sybert DR, Albarracin NS: An analysis of the flexor synovium in idiopathic carpal tunnel syndrome: Report of 625 cases. J Hand Surg Am 1992;17:1028-1030.

This patient has a deficiency of the anterior deltoid muscle, resulting in inferior subluxation of the humerus with associated glenohumeral instability. Axillary nerve injury during shoulder surgery accounts for 6% to 10% of brachial plexus injuries. In the posterior scapular region, the axillary nerve terminates by dividing into two main branches: the posterior terminal branch, which provides motor innervation to the teres minor and posterior deltoid muscles, and the anterior terminal branch, which provides motor innervation to the anterior and middle portions of the deltoid muscle. The deltoid determines the silhouette _of the shoulder and is a stabilizer of the humeral head._

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The AO Spine Classification Group has initiated a number of prospective studies on the treatment of cervical spondylotic myelopathy. In particular, Fehlings and associates showed that surgeon choice was important in selecting treatment, because the complications and outcomes were similar when comparing anterior to posterior approaches. Previously, studies showed more complications with posterior approaches. Further, anterior approaches are useful for more focal pathology in younger patients.

This patient has multiple hereditary exostoses. Note the multiple sessile osteochondromas on the humerus and ulna. A
characteristic bowing deformity of the forearm and pseudo-Madelung deformity of the wrist are also present.
Multiple hereditary exostoses is autosomal dominant. The putative tumor suppressive gene mutation is EXT1, EXT2. The risk of low-grade chondrosarcoma occurring is approximately 10%.
In most patients, the forearm deformity does not cause a major problem and can be treated nonoperatively. Correct Answe Multiple hereditary exostoses

Implants must resist translation in the axial, medial-lateral, and anteroposterior planes, as well as resisting rotation in the parasagittal, transverse, and coronal planes

Excessive resection of the common extensor origin posterior to the equator of the radiocapitellar joint may lead to iatrogenic lateral collateral ligament (LCL) injury, causing posterior lateral rotatory instability (PLRI). Patients may present with lateral elbow pain, a positive lateral pivot shift test, or mechanical symptoms/subjective instability when pushing up from a chair (positive chair rise test). PLRI is often provoked with combined elbow extension and forearm supination, as the posterior support for the radiocapitellar joint has been lost. Therefore, placing the forearm in pronation during elbow extension places the radiocapitellar joint in a more stable position and is less likely to induce pain or mechanical symptoms. Valgus instability and MCL tenderness would be associated with an MCL injury.

Tissues that are principally composed of collagen and fibroblasts are low signal on both T1 and T2 weighted sequences include tendons, ligaments, and fascial layers.
It is important to remember the appearances of common tissues on both T1 and T2 weighted images:
 T1 weighted T2 weighted
Fat High Moderate Tendons Low Low Ligaments Low Low Fascial layers Low Low Cortical bone Low Low Muscle Moderate Moderate Normal marrow High Moderate Soft tissue sarcomas Low High
Fluid (ganglions, effusions) Low High
Pigmented villonodular synovitis* Very low Very low
Signal drop out (very low signal on gradient echo sequences) Correct Answer: Tendons

**
This is a prospective comparative study but is not randomized or blinded and
is therefore a Level II therapeutic study. To qualify as Level I, it would need to be a high- quality randomized trial with narrow confidence intervals regardless of a significant difference or no difference in outcomes. Level III would be
case-control studies or retrospective comparisons. Level IV is case series and Level V is expert opinion.

This patient presents with HO 4 months after undergoing THA. Symptomatic HO may complicate nearly
7% of primary THA cases. Improvement in pain is expected within 6 months, and most patients will not need surgical treatment. Surgical excision may be warranted for symptomatic patients after full maturation of the HO, usually 6 to 18 months after the surgery. Patients can be followed with repeated serum alkaline phosphatase levels, which are elevated initially and should return to normal upon maturation of the HO. Alternatively, a bone scan can show decreased activity after the HO has matured. Twenty-five milligrams of indomethacin 3 times daily for 6 weeks or 1 dose of irradiation at 700 to 800 Gy is effective in the prevention of HO but not for the treatment of established HO.

The radiographic and clinical findings suggest a scapulothoracic dissociation with a widely displaced clavicular fracture and a laterally displaced scapula. These injuries have a high association with neurovascular injuries to the brachial plexus and subclavian artery. Emergent vascular evaluation with arteriography and possible vascular repair are indicated. This repair can be combined with open reduction and internal fixation of the clavicle to improve stability. Delay in treatment of these vascular injuries can be devastating.
REFERENCES: Iannotti JP, Williams GR (eds): Disorders of the Shoulder. Philadelphia, PA, Lippincott, 1999, pp 632-635.
Ebraheim NA, An HS, Jackson WT, et al: Scapulothoracic dissociation. J Bone Joint Surg Am 1988;70:428-432.

Rupture of the central slip of the extensor mechanism and a varying degree of lateral band volar migration are the pathologic entities in an acute boutonniere injury. Splinting the proximal interphalangeal joint in full extension allows reapproximation of the central slip to the base of the middle phalanx. Distal interphalangeal joint flexion is permitted to allow movement of the lateral bands distally and dorsally, preventing contracture.
REFERENCES: Newport ML: Extensor tendon injuries in the hand. J Am Acad Orthop Surg 1997;5:59-66.
Lovet WL, McCalla MA: Management and rehabilitation of extensor tendon injuries. Orthop Clin North Am 1983;14:811-826.

Gout is caused by the deposition of monosodium urate crystals in tissues, typically around joints. Common locations of gout include the great toe, heel, ankle, and knee. In approximately 50% of patients, the first affected location is the great toe. Gout commonly occurs inside a joint for two reasons - synovial fluid is a poorer solvent than plasma and lower temperatures (as in peripheral joints) favor crystallization.
Neutrophils ingest the crystals and release potent lysosomal enzymes. Punched lesions may be seen on radiographs in chroniCcases, and one can often see an overlying lip of cortex at the edge of the lesion.
Histologically, the tophi have several features: Acellular amorphous material
Macrophages
Foreign body giant cells
In this patient, the joint space is preserved on the plain radiographs. The biopsy specimen has the characteristiCfeatures of gout - acellular amorphous material, macrophages, and foreign body giant cells.
The treatment of gout includes nonsteroidal anti-inflammatory drugs and medications such as allopurinol and colchicines, which lower hyperuricemia.

With X-linked dominant, heterozygotes will have the condition. If a woman has this condition, then she will transmit it to 50% of her sons and daughters.
In contrast, affected men transmit the condition to all of his daughters (because the daughter gets his X chromosome), but to none of the sons because the son gets the Y chromosome.
With X-linked recessive, the patterns are different between women and men.
X-linked recessive woman: An X-linked woman with the recessive allele is a carrier, but she is not affected because the allele is recessive.
C arrier females (X-linked recessive) transmit the condition to 50% of her daughters (who become carriers) and 50% of her sons
(the sons are affected because their only X chromosome has the recessive gene). Correct Answer: 50% of the offspring will be affected

Open reduction of the vertical talus will most likely prevent problems.
With observation only, the patient is likely to stand or walk and develop pressure problems. Talectomy will not produce the most usable foot.
Achilles tenotomy will not produce significant correction by itself. Triple arthrodesis will concentrate stress and lead to ulcers.

- Proximal junctional kyphosis

The radiograph shows an olecranon fracture with articular comminution and depression of a large intra-articular fragment. This pattern is best treated with plate fixation to support the articular reduction.
Bailey et al reviewed 25 cases of olecranon fractures (simple and comminuted fracture patterns) treated with plate fixation. All 25 went on to union. There were no major complications reported. Twenty percent of patients underwent hardware removal at a later date for prominence.
Hak et al review the treatment options available for olecranon fractures. Simple intra-articular fractures without comminution are suitable for tension band fixation. Comminution of the articular surface is an indication for plate fixation and may benefit from bone graft to support depressed articular segments. Osteoporotic patients or fractures with severe comminution may do better with fragment excision and advancement of the triceps.

Co-planing the distal clavicle may lead to painful acromioclavicular joints in up to 35% of patients; this is felt to be related to destabilizing the distal clavicle. Intra-articular diagnosis of synovitis, degenerative joint disease, and superior labrum anterior and posterior lesions would have been identified at initial arthroscopy (not necessarily seen in open surgery). Ganglions are seen on MRI.
REFERENCES: Fischer BW, Gross RM, McCarthy JA: Incidence of acromioclavicular joint complications after arthroscopic subacromial decompression. Arthroscopy 1999;15:241-248.
Hazel RM, Tasto JP, Klassen J: Arthroscopic subacromial decompression: A 9-year follow-up. Arthroscopy 1998;14:419.
Barber FA: Coplaning of the acromioclavicular joint. Arthroscopy 2001;17:913-917.

The diagnosis of CRPS is complex. The IASP has approved diagnostic criteria to standardize both the diagnosis and the study of CRPS. The criteria are:
1. Continuing pain disproportionate to any inciting event
2. At least one symptom in three of the following four categories
1. Sensory: reports of hyperesthesia and/or allodynia
2. Vasomotor: reports of temperature asymmetry and/or skin color changes and/or skin color asymmetry
3. Sudomotor/edema: reports of edema and/or sweating changes and/or sweating asymmetry
4. Motor/trophic: reports of decreased range of motion (ROM) and/or motor dysfunction (weakness, tremor, dystonia) and/or trophic changes (hair, skin, nails)
3. At least one sign at the time of evaluation in two (for clinical diagnosis) or three (for inclusion in scientific studies) of the following categories
1. Sensory: evidence of hyperesthesia (to pinprick) and/or allodynia (to light touch and/or deep somatic pressure and/or joint movement)
2. Vasomotor: evidence of temperature asymmetry and/or skin color changes and/or skin color asymmetry
3. Sudomotor/edema: evidence of edema and/or sweating changes and/or sweating asymmetry
4. Motor/trophic: evidence of decreased ROM and/or motor dysfunction (weakness, tremor, dystonia) and/or trophic changes (hair, skin, nails)
4. No other diagnosis better explains the signs and symptoms.
Decreased sensation and focal numbness are not consistent with CRPS. Laboratory and imaging studies can be helpful in evaluating for the exclusion of differential diagnoses for CRPS, including infection, rheumatic disease, fracture, nonunion, tenosynovitis, or osteomyelitis.

Virtually all patients with metatarsus adductus will improve with time in the absence of active treatment.
C asts are not needed for the majority of cases because spontaneous improvement is by far the most common outcome. Reverse last shoes are not needed in the majority of patients with metatarsus adductus.
Most patients will not need surgery.
Equinus of the hindfoot is not part of the pathology in metatarsus adductus.

The most frequent complication is posttraumatic arthritis. With talar neck fractures,osteonecrosis is relatively common, occurring in up to 50% of patients. Fracture nonunion occurs in 10%to 12% of patients. Varus malunion can occur with medial comminution. Wound dehiscence and deep infection are much less frequently encountered.

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The patient has a classic hyperflexion neck injury with clinical resolution of neck pain upon follow-up. Furthermore, lack of historical radiculopathy or myelopathy, maintained normal neurological exam static, and dynamic radiographs rule out occult ligamentous or disk injury of the cervical spine. Accordingly, this patient’s cervical spine can be clinically and radiographically cleared without indication for further advanced imaging. However, the initial distractor of predominant neck pains should not overshadow the likelihood that this patient had a concussive event and remains symptomatic with headaches and inability to concentrate. Clearance to return to sport poses the risk of second impact and is not advisable. Prompt evaluation by traumatic head injury clinic or concussion clinic is imperative. Physical therapy may be beneficial if patient has persistant trapezial or periscapular symptoms but should not be prioritized over prompt concussion evaluation and treatment.

There is coxa vara of the hips and, by reconstructing the hip with a more valgus neck angle and maintaining the neck length, the reconstruction would reduce offset and increase leg length relative to the opposite hip.
90

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The imaging shows a displaced tibial spine avulsion. Non-displaced or minimally displaced fractures can be treated with long leg casting in extension, but displaced fractures require either open or arthroscopically assisted reduction and internal fixation with either screws or a suture construct. Although late knee instability is reported, an attempt at fracture fixation is recommended rather than acutely undergoing ACL reconstruction.

Several studies have demonstrated that degenerative symptomatic rotator cuff tears enlarge over time, which raises some concern regarding treating these injuries nonsurgically. The rate of rotator cuff tear enlargement at 2 years ranges from 20% to 49%, and at 5 years is estimated to be 50%. The risks associated with rotator cuff tear progression includes worsening fatty atrophy and fatty infiltration, decreased tendon pliability, and increased tendon retraction, which can lead to worse clinical outcomes following surgery.

This patient’s first femur fracture at age 7 was treated with a compression plate after he was struck by a motor vehicle. He sustained a second femur fracture at the end of the plate after a fall from a skateboard. Spica casting typically is recommended patients up to the age of 6 who weigh less than 25 kg. Tibial traction pins are not recommended for children because of risk for injury to the proximal tibial physis. A trochanteric entry rigid nail can be used, but a piriformis entry nail is not recommended for children because of risk for avascular necrosis of the femoral head. Removal of the plate and fixation with flexible titanium nails is a prudent option to fix the transverse fracture with a load-sharing device. Flexible nails are indicated for children weighing up to 50 kg.
CLINICAL SITUATION FOR QUESTIONS 33 THROUGH 36
A 10-year-old girl has right knee pain related to activity. An avid soccer player, she has noted pain after the first 15 minutes of running but no swelling or mechanical symptoms. Radiographs show a large 2-cm osteochondritis dissecans (OCD) lesion.

--The patient is provided with a medial unloader brace that provides substantial pain relief and he is able to work while wearing the brace. After 4 months he returns to work and says that while the brace enable him to work, it is uncomfortable. Consequently, his symptoms return when he is not wearing the brace and he is requesting a surgical intervention for his problem. What is the most appropriate surgical treatment?

1) Valgus-producing high tibial osteotomy (VPHTO)

2) Repeat knee arthroscopy

3) Total knee arthroplasty (TKA)

4) Medial meniscus transplant

--The patient is offered a VPHTO. What aspect of his history will determine the most appropriate VPHTO technique?

1) Prior arthroscopy

2) Current smoking history

3) BMI of 22

4) Age of 40

FOR QUESTIONS 13 THROUGH 16_
This patient has a classic presentation of postmeniscectomy medial compartment arthritis. The appropriate diagnostic study is weight-bearing radiographs to confirm the diagnosis. An MRI scan will reveal medial compartment arthritis but will not provide information about alignment. A CT scan would be appropriate to detect an occult fracture; however, this condition is not suspected in this clinical scenario. An ultrasound can provide information about fluid collection around the knee or a deep vein thrombosis; however, these conditions also are not suspected in this clinical scenario.
Because the patient has a correctable deformity (gaps 3 mm with valgus stress) and his symptoms are localized to the involved compartment, a trial of a medial unloader brace is appropriate both diagnostically and therapeutically. If unloading the medial compartment resolves the patient’s symptoms, he would be an excellent candidate for an osteotomy. An MRI scan may be obtained to evaluate ligamentous integrity or to evaluate degenerative involvement of the lateral and patellofemoral compartment for presurgicalplanning of an osteotomy; however, the integrity of the medial meniscus has no clinical importance in a patient with severe medial compartment arthritis. A repeat corticosteroid injection is not indicated within 1 month of his last injection, and referral to pain management is not appropriate with other options available to help this patient.A VPHTO is the appropriate intervention considering the patient’s young age, high-functional occupation,examination, radiographic findings, and response to medial unloader bracing. A revision knee arthroscopy would be appropriate for a recurrent medial meniscus tear, but not in a patient with severe medial compartment arthritis. The patient’s young age and high functional requirements are contraindications to TKA. The presence of severe arthritis is a contraindication to medial meniscus transplant. The patient is a candidate for a VPHTO. The technical options include a medial opening-wedge or a lateral closing-wedge osteotomy. Both techniques have advantages and disadvantages; however, a medial opening-wedge osteotomy is contraindicated in a smoker because of concern for nonunion. As a result,current smoking history is the only factor listed that would influence the technique used. The history of prior arthroscopy has no relevance in the decision about which type of osteotomy is appropriate. Normal BMI is between 18.5 and 24.9, so this patient’s BMI is considered normal and would not affect the surgical technique (if this patient were obese, a lateral closing-wedge osteotomy would be considered, but this is controversial). His age of 40 is an indication for HTO but does not influence technique.

-When reconstructing the anterior cruciate ligament (ACL), what is the most common source of potential autograft failure?

1) Graft choice

2) Tunnel position

3) Tibial fixation

4) Femoral fixation

_CLINICAL SITUATION FOR QUESTIONS 18 THROUGH 20_
A 25-year-old healthy woman injured her left knee while playing professional soccer. She has never injured this knee before. Examination 2 days after the injury occurred reveals the following: a moderate effusion, a positive Lachman test result, and mild lateral tenderness. Range of motion is between 20 degrees and 70 degrees. Radiographs reveal no fracture. An MRI scan reveals a complete rupture of the anterior cruciate ligament (ACL), an effusion, and bone bruises of the lateral femoral condyle and lateral tibial plateau. No meniscal tear is seen. The patient would like to continue playing at the professional level.

--What is the next treatment step?

1) Immobilization of the knee for 6 weeks, followed by rehabilitation and delayed ACL reconstruction

2) Immediate ACL reconstruction

3) Immediate rehabilitation for 6 months followed by ACL reconstruction if the patient is unstable in a brace

4) Immediate rehabilitation with delayed ACL reconstruction (when the athlete obtains full knee range of motion)

-What is this patient’s risk for developing osteoarthritis (OA) of the knee?

1) There is no risk for development of knee OA after reconstruction of the ligament.

2) There is no risk for development of knee OA after a double-bundle ACL reconstruction.

3) There is no evidence that ACL reconstruction reduces the incidence of knee OA.

4) There is 100% likelihood that she will develop knee OA after single-bundle ACL reconstruction.

-The patient asks if something about her anatomy has resulted in this injury. ACL anatomy differs between men and women in what manner?

1) There is no significant difference in ACL anatomy between men and women.

2) A woman’s ACL has a smaller cross-sectional area.

3) The cross-sectional area of a woman’s ACL is larger.

4) The intercondylar notch is wider in women than in men.

FOR QUESTIONS 18 THROUGH 20_
This patient has the clinical findings of an ACL rupture that is confirmed on MRI scan. She is a professional athlete and would like to return to her sport. Immediate ACL reconstruction in the setting of a knee with limited motion carries an increased risk for postsurgical stiffness. Delayed surgery after the patient regains range of motion is the preferred response. It has been shown that a woman’s ACL is smaller in the cross-sectional area.

-Figure 21 is the radiograph of a 31-year-old man who had left shoulder pain after a fall during a snow boarding jump. Residual displacement of 5 mm after closed reduction is most likely to result in which of the following?

1) Nonunion

2) Osteonecrosis

3) Altered rotator cuff mechanics

4) Normal shoulder function

-What strategy has proven most effective in preventing transmission of methicillin-resistant Staphylococcus aureus among teammates?

1) Separate players with infections in a separate locker room or changing area.

2) Treat teammates of the infected player with prophylactic antibiotics.

3) Cover any skin lesions with occlusive dressing during sporting activity.

4) Ban players with infections from any team event.

-Figure 23 is the T2 axial MRI scan of a 21-year-old man who was injured while playing for his college football team. His pain was aggravated with blocking maneuvers and alleviated with rest, and he had to stop playing because of the pain. What examination maneuver most likely will reproduce his pain?

1) Forward elevation in the scapular plane

2) External rotation and abduction

3) Flexion, adduction, and internal rotation

4) Flexion and abduction

_**CLINICAL SITUATION FOR QUESTIONS 24 AND 25**_
During the third quarter of a high school football game, a 16-year-old running back gets tackled and limps off the field. During the initial sideline evaluation, he has tenderness on the right iliac crest. He is a little dizzy, has a headache, and tells you, “I need to get back in the game to help the team score before halftime.”

-How can this scenario be managed most effectively?

1) Initiate rest, ice the iliac crest, and return to play when he is not limping.

2) Initiate rest, ice the iliac crest, and return to play after 20 minutes.

3) Keep the player on the sideline, perform a cognitive evaluation, and repeat the physical assessment.

4) Keep the player out of the game and send him emergently to the hospital for imaging.

-Sideline examination of this patient showed no cervical pain or tenderness; motor and sensory function were normal; and his pupils were equal, round, and reactive. He was alert and oriented to the score of game, time on the clock, and current quarter of play. His iliac crest had mild tenderness but no swelling or crepitus. The player states that he has a slight headache and is no longer dizzy. What is the most appropriate treatment?

1) Return him to the game and observe his play closely.

2) Do not return to the game and do not allow play for the remainder of the season.

3) Do not return to the game and begin a graduated return-to-play protocol for future games.

4) Perform a sideline noncontact exercise testing examination and return him to the game if he is asymptomatic.

FOR QUESTIONS 24 AND 25_
Although this player limps off the field, the fact that he felt dizzy, had a headache, and did not initially recognize that he was playing in the third quarter indicates that he sustained a concussion. The player should be kept out of the game until a cognitive examination and repeat physical assessment is completed.Even if his physical symptoms have resolved, a certain period of time has expired, or he states that he is“ready,” he should not be returned to play prior to this assessment. Sending the patient to an emergency department should be considered only after this assessment and appropriate initial sideline treatment is initiated. The Consensus Statement on Concussion in Sport recommends that no athlete with concussion symptoms be returned to same-day play. This patient still has a slight headache, but even if this resolved he should not return to the game. Adolescents and high school athletes may have neurophysiological deficits that may not be evident on the sideline, or they may have a delayed onset of symptoms. A graduated return to play for future games is recommended.
_CLINICAL SITUATION FOR QUESTIONS 26 THROUGH 29_
A 32-year-old woman has a 2-year history of progressively worsening right groin pain that is exacerbated by activity. She reports no traumatic injury and an extensive work-up by her gynecologist has ruled out an intrapelvic source of her pain. The patient is a recreational athlete and exercises regularly in the gym.The pain is preventing her from performing these activities. She reports no catching or locking symptoms.Her examination reveals a physically fit female (BMI of 20) with limited right hip range of motion. She has no tenderness to palpation around the hip. While lying supine and bringing her hip into progressive flexion with internal rotation and adduction, her groin pain is reproduced. She has normal limb lengths and demonstrates weakness secondary to pain with hip flexion on the affected side.

-What is the most likely cause of this patient’s groin pain?

1) Femoroacetabular impingement (FAI)

2) Osteoarthritis of the sacroiliac joint

3) Intra-articular loose body

4) Trochanteric bursitis

-The patient is enrolled in physical therapy for 6 weeks with little improvement of her hip symptoms.What is the next most appropriate diagnostic test to determine the presence of an associated acetabular labral tear in this patient?

1) Diagnostic arthroscopy of the hip

2) MRI scan of the hip

3) MRI arthrogram of the hip

4) Ultrasound of the hip

-The study obtained in confirms the presence of an anterosuperior acetabular labral tear and pincer morphology of the acetabulum. What is the most likely location of a chondral injury associated with these findings?

1) Posteroinferior acetabulum

2) Posterosuperior acetabulum

3) Femoral head above the fovea

4) Femoral head below the fovea

-The patient experienced little improvement with activity modification and physical therapy. An intraarticular corticosteroid injection provides excellent but short-lived pain control. She requests surgical treatment for her hip and she is counseled regarding arthroscopy and consent is obtained. Intraoperatively,a capsulolabral separation is observed with an underlying pincer lesion. No articular cartilage injury is seen. What treatment is most appropriate considering these findings?

1) Suture anchor repair of the labral tear and no bony resection

2) Suture anchor repair of the labral tear and bony resection of the pincer lesion

3) Debridement of the labral tear and bony resection of the pincer lesion

4) Debridement of the labral tear with no bony resection of the pincer lesion

FOR QUESTIONS 26 THROUGH 29_
The clinical scenario, examination, and MRI scans are consistent with a pincer-type FAI. The decreased range of motion is secondary to the pain produced by the continued abutment of the femoral head against the anterosuperior acetabulum. Flexing the hip while internally rotating and adducting the leg recreates this contact and is typically painful. No clinical signs suggest sacroiliac joint arthritis, an intra-articular loose body, or trochanteric bursitis, although these are all diagnoses that should be considered in a patient with a painful hip. The most sensitive and specific study to detect an acetabular labral tear is an MRI arthrogram of the hip. This study should be obtained in this patient to evaluate the labrum as well as the status of the articular cartilage. An MRI scan without intra-articular contrast is not as sensitive as an arthrogram. An ultrasound can provide a dynamic assessment of the hip and help in the setting of a snapping hip; however, this study is not reliable to determine the presence of a labral tear. In the setting of pincer FAI, the forced leverage of the anterosuperior femoral head upon the anterior acetabulum results in abnormal forces against the posteroinferior acetabulum. This continued force can lead to a chondral lesion in this location know as a “counter-coup” injury. Chondral lesions of the femoral head are rare in the setting of pincer FAI. The posterosuperior quadrant does not experience increased force and rarely sustains chondral injuries. The patient is a young, active individual with no pre-existing degenerative changes, so repair of the tear with bony resection of the pincer lesion is the most appropriate treatment.A capsulolabral detachment should be repaired because these tears can heal and the labrum functions as a seal, preventing egress of synovial fluid from the joint space. If the pincer lesion is not resected, the patient will continue to experience abnormal contact and the repair will likely fail. There is no evidence that the patient has a cam impingement, and recontouring of the femoral head/neck junction is not appropriate. Simple debridement should be reserved for intrasubstance tears of the labrum, which would not be expected to heal with repair.
_**CLINICAL SITUATION FOR QUESTIONS 30 THROUGH 32**_
Figures 30a and 30b are the radiographs of a 20-year-old college multisport athlete who has had longstanding pain in his left hip. He denies any specific event that initiated his pain, but he notes that he had hip problems when he was an infant. He denies pain with activities of daily living, but he
believes his pain is increasingly limiting his ability to exercise. He localizes the pain to his groin. He denies low-back or buttock pain or pain that radiates down his leg.

-What examination findings are most consistent with the pathology seen in the radiographs?

1) Pain with resisted hip flexion

2) Pain with a half sit-up, plus tenderness at the pubic ramus

3) Pain with a combination of hip flexion, adduction, and internal rotation

4) Tenderness to palpation at the greater trochanter

-What is the most likely diagnosis for the source of this patient’s pain?

1) Cam-type femoroacetabular impingement

2) Pincer-type femoroacetabular impingement

3) Hip flexor strain

4) Athletic pubalgia

-Images from an MRI scan of this patient’s left hip are shown in Figure 30c through 30e. What is the most likely cause of his acute pain?
1) Significant cartilage loss on the acetabulum

2) Labral tear

3) Femoral neck stress fracture

4) Tendonopathy of the rectus femoris

FOR QUESTIONS 30 THROUGH 32_
This patient has cam-type femoroacetabular impingement. Decreased internal rotation and a positive impingement test (forced flexion, adduction, and internal rotation) are classic findings. The lack of pain with resisted hip flexion makes hip flexor strain unlikely, and the lack of tenderness at the greater trochanter renders trochanteric bursitis unlikely. Although athletic pubalgia can be a source of longstanding groin pain, he lacks the pain with a resisted sit-up and tenderness along the pubic ramus that is frequently noted in patients with pubalgia. His radiographs reveal a focal femoral neck prominence consistent with cam impingement, although pistol grip deformities and flattening of the lateral femoral head are often present as well. His MRI scan shows a labral tear, which is common in cam impingement.Surgical treatment for cam impingement can be effective for symptomatic patients. Even among highlevel athletes, open surgical dislocation of the hip has been shown to have good results. Most patients with cam impingement can be treated with arthroscopic osteoplasty and achieve results comparable to those realized with open surgical dislocation. The literature describes success in terms of athletes returning to sports (even professional athletes) to be approximately 90% after arthroscopic treatment.Byrd and Jones described 5 patients who developed transient neurapraxias that resolved uneventfully.The patients in his series who had concomitant microfracture had a 92% return to sports within the follow-up period. Cam impingement has long been thought to be associated with a history of a slipped capital femoral epiphysis. The capitis in these patients is displaced posteriorly, resulting in a prominent anterior femoral neck and decreased hip internal rotation. Pincer impingement is associated with a deep acetabulum, such as protrusion acetabula and acetabular retroversion. A patient who underwent a periacetabular osteotomy can develop a more retroverted acetabulum as well.

-A 25-year-old recreational soccer player has recurrent shoulder dislocations. He first dislocated his shoulder playing football in high school, was treated in a sling for 6 weeks, and returned to play for the remainder of the season. He did well until 2 years later when he reinjured the shoulder. He says that his shoulder dislocates with little injury and always “feels loose.” Examination reveals anterior instability and an MR arthrogram reveals an anterior-inferior labral tear and surgical treatment is recommended. He inquires about the benefits of arthroscopic vs open procedure. Which of the following statements reflects an advantage associated with arthroscopic procedures compared to open stabilization?

1) Range of motion might be slightly better after an arthroscopic procedure.

2) Rate of recurrent instability is lower after an arthroscopic procedure.

3) Rates of return to work are higher after an arthroscopic procedure.

4) Rates of return to sports are higher after an arthroscopic procedure.

-Figures 34a and 34b are the radiographs of a 38-year-old woman who had increasing left hip pain with activity. She noted no lower back or buttock pain and no pain along her lateral thigh. The pain usually only bothers her with running and cycling.
Nonsteroidal anti-inflammatory drugs helped initially but are not relieving her pain now. Examination with the patient supine reveals pain with internal and external rotation of her hip
with her hip and knee in an extended position. With her hip flexed to 90 degrees, she has internal rotation only to neutral, but full external rotation. What is the most likely diagnosis?
1) Cam-type femoroacetabular impingement

2) Pincer-type femoroacetabular impingement

3) Intra-articular loose body

4) Snapping psoas tendon

-A 24-year-old former high school wrestler had anterior cruciate ligament (ACL) reconstruction with hamstring autograft 6 years ago. He now experiences daily instability of his knee with routine activities including walking. Examination reveals a grade 3+ Lachman with a soft endpoint, varus laxity at 30 degrees, and a positive dial test at 30 degrees that dissipates at 90 degrees of knee flexion. He has mild medial joint line tenderness. When walking, there is a slight varus thrust. What treatment is most likely to lead to a successful outcome?

1) Hamstring autograft

2) Revision ACL reconstruction and posterior cruciate ligament (PCL) reconstruction

3) Revision ACL reconstruction and posteromedial corner reconstruction

4) Revision ACL reconstruction and posterolateral corner reconstruction

-A 49-year-old man is seeking a second opinion for continued knee pain and swelling. He went to his primary doctor for swelling “on top of his knee,” and he says his doctor drained some clear fluid. He noted that his condition improved for about 1 week before the swelling returned. He now has increasing pain and redness around his kneecap.
Examination reveals significant swelling of his prepatellar bursa,with erythema over the bursa that extends to the surrounding skin. His temperature in the office is 101.7°F. What is the next step in treatment for this patient?

1) Initiate oral antibiotics for 7 days.

2) Reaspirate the bursa and inject a corticosteroid.

3) Recommend padding the patella for kneeling and ice.

4) Perform an open bursectomy and start intravenous antibiotics.

_CLINICAL SITUATION FOR QUESTIONS 37 AND 38_
An 18-year-old right-hand-dominant college freshman who is a third baseman has pain in his right shoulder after using his outstretched right arm for support while diving to catch a low line drive. He describes pivoting on his right hand and arm while reaching out to make the catch with his left-hand glove. He had pain in his shoulder but was able to finish the game with some pain while throwing. Five days later, he experiences popping pain deep in his shoulder that has improved since the injury but continued to be bothersome deep in the shoulder with higher-velocity throwing. Examination demonstrated decreased internal rotation, posterior pain with cross-body adduction and posteriorly directed force, and full rotator cuff strength. Radiograph findings were normal. After 6 weeks of physical therapy (PT), his range of motion has improved but he continues to experience deep pain with therapy. Examination shows symmetric range of motion and posterior pain with the jerk test and Kim test. His rotator cuff is strong.Figure 37a Figure 37b

-What is the next step in treatment?

1) Continued PT

2) Subacromial injection

3) CT scan

4) MRI arthrogram

-T1-weighted, fat-saturated MRI scans are shown in Figures 37a and 37b. What is the next step intreatment?

1) Open reduction internal fixation (ORIF)

2) Rotator cuff repair

3) Labrum repair

4) Chondroplasty

FOR QUESTIONS 37 AND 38_
Examination findings of posterior glenohumeral tenderness, decreased internal rotation, and reproduction of symptoms with a posterior stress test indicate a posterior shoulder injury or instability. The jerk test,with the patient seated, positions the arm in forward flexion and internal rotation with elbow flexion. One hand of the examiner is placed on the patient’s distal clavicle and scapular spine and the other hand grasps the elbow. The arm is jerked posteriorly while the shoulder girdle is jerked anteriorly, which creates pain as the posteriorly subluxated humeral head relocates into the glenoid fossa. During the Kim test, the patient is seated with the arm in 90 degrees of abduction. While the arm is elevated 45 degrees diagonally (forward flexion and adduction), the examiner applies an axial load to the elbow and a downward and posterior force to the upper arm. A positive result causes a sudden onset of posterior shoulder pain. A positive jerk test combined with a positive Kim test has a 97% sensitivity for posterior instability. After extensive PT, the patient continues to have examination findings consistent with posterior shoulder injury or instability, so an MRI scan or MRI arthrography would be helpful to assess for any pathology.A subacromial injection is not indicated by this examination, which shows a strong rotator cuff and no demonstrated bursal-sided symptoms. A CT scan can be helpful in scenarios involving bony pathology,but an MRI is indicated at this stage in the evaluation of soft tissue. Although continuing PT may help to abate symptoms, the patient was continuing to have symptoms with PT. The MRI arthrogram shows a complex posterior labrum tear at the inferior to mid glenoid with separation of labrum from the glenoid. Because the examination findings are consistent with the MRI findings and nonsurgical treatment has failed to resolve symptoms, the next step is to recommend surgical treatment with labrum debridement and/or repair. No examination or MRI findings indicate a need for injection, rotator cuff repair, ORIF, or chondroplasty unless incidental intrasurgical findings are found.

A high school athlete sustained a noncontact injury to his right knee. He says that during a football game he felt a pop and his leg gave way. He attempted to continue to play but was unable secondary to pain.Five days after the injury, radiographs of his right knee do not reveal any abnormalities. On examination,he has an effusion on the injured side and no joint line tenderness. His range of motion is full extension to 110 degrees of flexion. At 20 degrees of flexion, he has increased anterior translation compared to the contralateral, uninjured left side. At 90 degrees of flexion, the tibia does not translate posteriorly. As his knee is moved from full extension into flexion with an internal rotation and valgus force, you notice a“clunk” within the knee. What is the most likely biomechanical basis for the “clunk”?

1) In extension, the medial tibial plateau is subluxated; as an internal rotation/valgus force is applied in conjunction with flexion, the medial tibial plateau reduces.

2) In extension, the medial tibial plateau is reduced; as an internal rotation/valgus force is applied in conjunction with flexion, the medial tibial plateau subluxates.

3) In extension, the lateral tibial plateau is reduced; as an internal rotation/valgus force is applied in conjunction with flexion, the lateral plateau subluxates.

4) In extension, the lateral tibial plateau is subluxated; as an internal rotation/valgus force is applied in conjunction with flexion, the lateral plateau reduces.

_**CLINICAL SITUATION FOR QUESTIONS 40 THROUGH 42**_
A 9-year-old boy was injured while playing soccer. His examination revealed painful range of motion between 5 degrees and 75 degrees. There is tenderness on the medial side of his knee. There is no effusion, a grade 1A Lachman, and severe pain over the medial epicondyle of the knee. Varus stress is negative and pain is elicited with valgus stress. Initial radiographs were negative for abnormality.

-What is the next diagnostic step?

1) Repeat radiographs while the patient is weight bearing

2) Ultrasound of the lower extremity and calf

3) Stress radiographs

4) CT scan

-What is the most likely area of injury?

1) Femoral attachment of the medial collateral ligament

2) Tibial attachment of the medial collateral ligament

3) Hypertrophic zone of the growth plate

4) Proliferative zone of the growth plate

FOR QUESTIONS 40 THROUGH 42_
This patient likely has a physeal injury to the distal femoral physis. Stress radiographs or an MRI scan will most reliably reveal this diagnosis. The growth plate, when injured, is most commonly fractured through the hypertrophic zone of cartilage, its weakest point. This patient is optimally treated in a cylindrical or long-leg cast. Younger patients can be treated with a hip spica with a leg extension.

-An otherwise healthy 15-year-old wrestler has a 6-cm cutaneous lesion on the posterior aspect of his right elbow that he reports as a spider bite. What is the most likely diagnosis?

1) Psoriasis

2) Tinea corporis

3) Herpes simplex virus

4) Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA)

_CLINICAL SITUATION FOR QUESTIONS 44 AND 45_
Figure 44 is the MRI scan of a 14-year-old soccer player who injured his right knee during a game.He describes feeling a “pop” and he needed help walking off the field. His knee is visibly swollen. A Lachman test demonstrates asymmetry with no endpoint.

-Range of motion of the knee is between 0 degrees and 70 degrees. What is the most appropriate treatment option?

1) Nonweight-bearing activity with crutches

2) Microfracture of the chondral defect

3) Immediate anterior cruciate ligament (ACL) reconstruction

4) Delayed ACL reconstruction

-The patient has no postsurgical complications and begins physical therapy rehabilitation. The boy and his parents stress they “want to get the therapy over with as fast as possible” to expedite his return to sports,and the surgeon and rehabilitation team consider their request. Compared to nonaccelerated rehabilitation,patients who follow an early accelerated rehabilitation protocol experience

1) increased laxity.

2) no differences in long-term results.

3) increased risk for graft failure.

4) lower Knee Injury and Osteoarthritis Outcome Scores (KOOS).

FOR QUESTIONS 44 AND 45_
The Lachman test is the most sensitive examination for acute ACL injuries. ACL injury rates are higher in women than in men. This likely is attributable to anatomic differences (smaller notches, smaller ligaments, and different landing biomechanics). Lateral meniscal tears are more common than medial tears. The anterior drawer test is accentuated with 30 degrees of external rotation of the tibia. The MRI scan shows bone bruises consistent with an ACL tear. It is also always necessary to examine other structures of the knee in patients with ACL tears. All ligaments of the affected knee should be assessed.Lateral meniscal tears are frequently associated with ACL tears. Medial meniscal tears and posterolateral corner deficiency are also possible. Randomized clinical trials comparing an early accelerated vs nonaccelerated rehabilitation have demonstrated no significant differences in long-term results. These studies did not address timing of return to play with an early accelerated rehabilitation program. At 2 and 3 years postsurgically, there are no differences in laxity, number of graft failures, or KOOS scores.

-Chronic traumatic encephalopathy (CTE) is a neurodegenerative disease that is characterized by

1) onset most often by age 30.

2) a temporary state of neuronal and axonal derangement.

3) manifestations of affect such as apathy, irritability, and suicidal ideation.

4) absence of gross pathological brain changes upon autopsy.

-In the shoulder position of 90-degree forward flexion and internal rotation, what is the most important static stabilizer of the glenohumeral joint?

1) Rotator interval

2) Infraspinatus

3) Anterior band of the inferior glenohumeral ligament

4) Posterior band of the inferior glenohumeral ligament

_**CLINICAL SITUATION FOR QUESTIONS 48 AND 49**_
A 17-year-old high school wrestler sustains an abrasion over the posterior aspect of his right elbow during a match. During the next few days the abrasion becomes erythematous and he is placed on oral cephalexin 500 mg four times per day. The erythema extends proximally despite the antibiotic regimen. The patient is afebrile, there is no fluid collection associated with the lesion, and his elbow joint is not involved.

-What is the most appropriate treatment?

1) Switch to oral trimethoprim-sulfamethoxazole double-strength twice per day for 10 to 14 days

2) Switch to oral ciprofloxacin 500 mg twice per day for 10 to 14 days

3) Begin cefazolin 1 gram intravenously (IV) every 8 hours for 7 to 10 days

4) Irrigation and debridement with empiric IV antibiotic coverage

-Assuming that the lesion can be covered appropriately and there is no drainage from the lesion, when should the patient be allowed to safely return to wrestling?

1) When the absence of pain is reported by the wrestler for 3 consecutive days

2) When 72 hours of antibiotics have been administered and there is no extension of the lesion for 48 hours

3) When laboratory values are within defined limits and the patient remains afebrile for 3 days

4) When the lesion has decreased in size by 50%

FOR QUESTIONS 48 AND 49_
This patient has cellulitis, which is typically caused by group A Streptococcus or Staphylococcus. The patient’s lack of improvement with first-line antibiotics is concerning for methicillin-resistant Staphylococcus aureus (MRSA) infection. MRSA cellulitis is becoming more prevalent in young athletes,and a high index of suspicion is required to provide appropriate intervention during this
aggressive disease process. The diagnosis is typically made clinically without the use of cultures. Oral trimethoprimsulfamethoxazole (a sulfonamide-class drug) double strength twice daily for 10 to 14 days or doxycycline (a tetracycline-class drug) 100 mg twice daily for 10 to 14 days are recommended for first-line treatment of suspected MRSA cellulitis. There is no indication to proceed with irrigation and debridement; however, if the patient develops a soft-tissue abscess or the underlying joint becomes involved, this would be an appropriate intervention. Switching the athlete to an IV cephalosporin (cefazolin) is not likely to be effective against the presumed resistant bacteria.
Ciprofloxacin (a fluoroquinolone-class drug) is effective against many bacteria, but not MRSA. The current recommendation for wrestlers with cellulitis is that return to competition be allowed after 72 hours of antibiotic treatment if there has been no extension of the cellulitis for 48 hours, the lesion can be covered, and there is no drainage from the lesion. The other responses are not current recommendations for return to competition.

-A 19-year-old linebacker underwent a coracoid transfer procedure for recurrent anterior glenohumeral instability. At his 1-week postsurgical check-up, his incision is doing well; however, he reports numbness over the lateral aspect of his forearm. What nerve may have been injured during his surgery?

1) Axillary

2) Median

3) Musculocutaneous

4) Radial

-What is the most important genetic element that distinguishes community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) from hospital-acquired MRSA?

1) Beta-lactamase

2) Penicillin-binding protein 2a

3) Panton-Valentine leukocidin (PVL)

4) Staphylococcus cassette chromosome (SCCmec) type I

_CLINICAL SITUATION FOR QUESTIONS 52 THROUGH 54_
A 13-year-old baseball player fell while rounding second base 2 days ago. He said it felt like his knee buckled when he turned toward third base. He could not finish the game, but was able to bear weight with a limp. He has had no previous knee injuries, but now complains of pain in his right knee. Initial examination demonstrated an effusion, tenderness at the proximal medial collateral region and medial patellofemoral retinaculum, decreased range of motion, and patella apprehension. He was otherwise ligamentously stable. No other noteworthy physical findings were found.

-What is the next treatment step?

1) Radiographs

2) Arthroscopy

3) MRI scan

4) Duplex ultrasound

-What do the radiographs shown in Figures 52a and 52b reveal?

1) Medial femoral chondyle physeal widening

2) Osseous or osteochondral loose fragment

3) Osgood-Schlatter disease

4) Patella nondisplaced fracture

-Figures 52c and 52d show the proton density fat-saturated MRI scans. Treatment at this stage includes arthroscopy and

1) early functional rehabilitation.

2) proximal realignment alone.

3) attempted internal fixation.

4) medial collateral ligament (MCL) repair.

FOR QUESTIONS 52 THROUGH 54_
This patient’s examination indicates a patellar or peripatellar knee injury. Initial evaluation with radiographs will assess for fracture, subluxation, or osteochondral injury. Examination findings did not demonstrate a need for emergent surgery, an MRI scan, or an ultrasound, so radiographs are the initial diagnostic imaging choice. Radiographs show an osseous or osteochondral loose fragment.
There is no evidence of obvious nondisplaced fracture or physeal changes. In suspected patella dislocation or subluxation with loose fragment seen on radiographs, an MRI scan is indicated. Lateral release alone is seldom indicated in a knee that was normal before injury. Acute proximal realignment has not been shown to alter long-term outcomes for first-time dislocators. The examination and MRI scan did not indicate a need for MCL repair. Closed reduction of the osteochondral fragment would not be indicated or appropriate for this injury. Treatment should consist of arthroscopy or arthrotomy and attempted internal fixation of this fragment. If fixation is not possible, the loose body can be removed.

-While obtaining informed consent for a lateral closing-wedge osteotomy, what complication should be discussed with the patient as exclusive to this procedure and not encountered in medial opening-wedge osteotomy?

1) Compartment syndrome

2) Plate breakage

3) Neurologic injury

4) Proximal tibiofibular joint disruption

_**CLINICAL SITUATION FOR QUESTIONS 56 THROUGH 58**_

Figure 56 is the MRI scan of a 15-year-old girl who had left knee pain after sustaining a noncontact twisting injury while playing soccer. She reported severe pain initially that has since improved. On examination, she had a large knee effusion with lateral joint line tenderness. Range of motion is from 5 degrees of extension to 70 degrees of flexion. She wishes to return to sports at her preinjury level of activity.

-What examination test is most likely to reveal abnormal findings?

1) Pivot shift test

2) Quadriceps active test

3) Patellar apprehension test

4) External rotation recurvatum test

-What is the most appropriate treatment?

1) Delayed ligament reconstruction

2) Physical therapy and functional bracing

3) Immediate ligament repair

4) Immediate ligament reconstruction

-What is the most likely mechanism of injury?

1) External rotation

2) Posterior translation

3) Hyperextension and varus

4) Anterior translation and internal rotation

FOR QUESTIONS 56 THROUGH 58_
The MRI scan shows a bone bruise of the lateral femoral condyle and lateral tibial plateau. This injury pattern is commonly associated with anterior cruciate ligament (ACL) rupture and an abnormal pivot shift test result. Treatment of an ACL tear in a high-demand athlete should consist of ligament reconstruction.In this patient, surgery should be delayed until she regains full range of motion to minimize risk for arthrofibrosis after surgery. Recent analysis has shown that the noncontact mechanism is more consistent with anterior translation, affecting both the medial and lateral compartments. The bone bruise in the lateral femoral condyle occurs more anterior than that of the medial femoral condyle, suggesting that internal rotation has occurred. The external rotation recurvatum test assesses for posterolateral corner injury, and a positive quadriceps active test is consistent with posterior cruciate ligament rupture. An abnormal patellar apprehension test result is suggestive of patellar instability. Nonsurgical treatment is unlikely to result in sufficient stability if this patient returns to sports at her preinjury level of activity.Primary ACL repair is associated with high failure rates. Although the precise mechanism of injury varies,injuries can be broadly classified into contact and noncontact injuries. Noncontact injuries occur with the knee in slight flexion, valgus, and internal rotation, and contact injuries typically involve a lateralside impact producing a valgus force to the knee. The valgus component of noncontact injuries has been thought to cause mainly lateral compartment bone bruising. Posterior translation is the most common mechanism of posterior cruciate ligament rupture, and hyperextension and varus is associated with posterolateral corner injury.

-A 12-year-old boy who plays multiple sports has had insidious-onset heel pain while running for 4 months. On examination, he had ankle dorsiflexion of 5 degrees. The squeeze test result was positive and the Thompson test result was negative. He has no pain with forced ankle plantar flexion. What is the most likely diagnosis?

1) Achilles rupture

2) Gastrocnemius strain

3) Calcaneal apophysitis

4) Os trigonum syndrome

_CLINICAL SITUATION FOR QUESTIONS 60 AND 61_
A 15-year-old boy has had shoulder pain for 4 weeks during the middle of baseball season. The patient says his pain is “all over my shoulder.” Examination reveals tenderness to palpation over the anterolateral aspect of the shoulder. Internal and external rotation range of motion is restricted.
Radiographs show metaphyseal sclerosis.

-What is the most significant risk factor for the development of little leaguer’s shoulder in this scenario?

1) Recent increase in the number of pitches

2) Gender (male)

3) Glenohumeral internal rotation deficit

4) Genetic factors

-This boy’s parents are eager to get him back on the field as soon as possible. What is the most appropriate treatment option?

1) Screw fixation of the epiphysis

2) Arthroscopic debridement

3) A shut-down period until the boy is asymptomatic, and gradual return to pitching via a throwing program

4) An intra-articular cortisone injection

FOR QUESTIONS 60 AND 61_
Although a recent increase in the number of pitches may have contributed to this patient’s development of little leaguer’s shoulder, the most significant overall factor is age. 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. Genetic factors and gender have not been studied in association with little leaguer’s shoulder. 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 baseline pitching is implemented until the patient is back to baseline. This protocol has a long-term success rate exceeding 90%.

-is an arthroscopic view of the intercondylar notch of a right knee from an anterolateral portal.What is the main function of the structure delineated by the black asterisks?

1) Resist anterior translation during knee flexion

2) Resist posterior translation during knee flexion

3) Resist rotatory loads during knee flexion

4) Resist rotatory loads during knee extension

-A 25-year-old wrestler has been experiencing increasing left knee pain since his last professional cage fight. He complains of both pain and instability on the medial side of his left knee. Examination reveals a grade 3 Lachman and pseudolaxity with valgus stress. Dial test findings are normal. Radiographs show medial degenerative changes and 5 degrees of varus alignment. What is the most appropriate treatment?

1) Rehabilitation with vibration-platform weight-bearing squats

2) Anterior cruciate ligament (ACL) reconstruction with autograft bone-tendon-bone

3) High-tibial osteotomy (HTO)

4) HTO plus ACL reconstruction at the same time

-What is an example of cognitive rest after concussion?

1) Playing chess

2) Increasing reading

3) Working online

4) Limiting video games

_**CLINICAL SITUATION FOR QUESTIONS 65 THROUGH 67**_

Figure 65 is the radiograph of a 24-year-old man who had left knee pain after sustaining a twisting injury while playing Ultimate Frisbee. On examination, he had a large effusion with tenderness over the lateral joint line. Pivot shift testing results were positive. Prone dial testing results at 30 degrees and 90 degrees were negative. An MRI scan shows a tear of the anterior cruciate ligament (ACL).

-Based on the radiograph, the attachment for which structure has been disrupted?

1) Iliotibial band

2) Popliteus tendon

3) Lateral meniscus

4) Lateral capsular ligament

-Compared with a transtibial technique, what effect will drilling the femoral tunnel through the anteromedial portal have?

1) Produces a longer femoral tunnel

2) Improves visualization while drilling

3) Should be performed at 90 degrees of knee flexion

4) Allows for independent access to the anatomic femoral insertion

-The patient requests anatomic double-bundle ACL reconstruction. Compared with transtibial singlebundle ACL reconstruction, anatomic double-bundle ACL reconstruction is more likely to

1) restore improved knee kinematics.

2) allow for earlier return to sports.

3) result in better clinical outcomes scores.

4) be associated with lower surgery cost.

FOR QUESTIONS 65 THROUGH 67
The radiograph shows a Segond fracture, an avulsion fracture involving the lateral capsular ligament.
This radiographic finding has been associated with ACL rupture in 75% to 100% of cases. Drilling the femoral tunnel through the anteromedial portal allows for independent access to the native femoral attachment. Fiber orientation is more oblique than with a transtibial technique and more closely resembles that of the native ligament. Double-bundle reconstruction attempts to duplicate native ACL anatomy.Biomechanical studies have shown that double-bundle reconstruction more
closely reproduces normal knee kinematics; however, this technique does not offer a clear advantage in terms of clinical outcomes.The iliotibial band inserts onto Gerdy’s tubercle. The popliteus tendon originates from the lateral femoral condyle. The lateral meniscus attaches near the intercondylar eminence at the anterior and posterior meniscal roots. Recent advances in ACL reconstruction focus on restoring the native ACL anatomy.Studies have determined that a knee flexion angle of 110 degrees is optimal to avoid blowout of the back wall and injury to the lateral structures while drilling.
Femoral tunnel length is typically shorter than with a transtibial approach and decreases with higher-flexion angles. Double-bundle reconstruction is associated with higher surgical costs because of the need for additional fixation and, in the case of allograft reconstruction, a second graft.

-A 42-year-old man has increasing pain and, to a lesser extent, some occasional left knee instability.Several years earlier he sustained a noncontact twisting injury to his knee. He had some initial soreness and pain but was able to resume his normal activities while avoiding sports. On examination, the patient has medial joint line pain, a grade 2+ Lachman, and a slight varus thrust. His radiographs reveal mild-tomoderate medial compartment osteoarthritis with varus alignment. What surgical treatment strategy likely will alleviate his pain?

1) Distal femoral osteotomy

2) Unicompartmental knee replacement

3) High tibial osteotomy (HTO), lateral closing wedge

4) HTO, medial opening wedge with decreased tibial slope

_**RESPONSES FOR QUESTIONS 69 THROUGH 71**_

The patient most likely to require late subtalar fusion for post-traumatic arthritis is a male patient with a Sanders Type III fracture treated with ORIF.
The Sanders classification system seems to remain prognostic for injury severity. It has been shown that greater articular injury is associated with greater risk of arthritis, irrespective of patient gender and occupation. In current reviews, type III fractures are 6.5 times more likely to develop PTA and 4 times more likely to require an ST fusion than Sanders type II fractures. Post-traumatic arthritis of the subtalar joint is a common complication.
Successful salvage can be achieved with a subtalar arthrodesis.
Howard et al reported on complications following management of displaced intra-articular calcaneal fractures. 469 patients were randomized into ORIF and non-operative groups. ORIF patients were more likely to develop complications (overall 25% vs 18% of non-op) with fractures of increasing severity (Sanders IV) developing more complications regardless of management strategy.
Sanders et al. reviewed the operative treatment of displaced intra-articular calcaneal fractures. Based on the results of this comparative analysis, the Sanders classification remains prognostic; after a minimum of 10 years, type III fractures were 4 times more likely to need a fusion than type II fractures.
Illustration A shows the Sanders classification. Incorrect Answers:
Answers 1,3-5: Functional outcomes and arthritis will be determined by the
amount of cartilage damage. This is directly correlated with initial injury, fracture pattern (Sanders) and reduction techniques. Worker compensation are associated with worse functional outcome scores, not post-traumatic arthritis.

Nonoperative treatment will allow the patient to retain maximum mobility of the hips.
Operative treatment carries substantial risk of avascular necrosis, stiffness, and redislocation. These risks are not worth taking in view of the patientâs limited muscle strength about the hips. In addition, the motor level alluded to (L2-L3) means that she will not have sensation of pain from the hips.

DISCUSSION: A chronic patellar tendon rupture is a difficult complication to manage. Patients typically present with both inability to extend their leg and instability of the extremity, oftentimes associated with multiple falls.
Attempts at secondary repair have been associated with high failure rates whereas the use of an extensor mechanism allograft has been shown to more effectively restore active extension in a substantial percentage of patients. Important aspects of the technique include fully tensioning the graft in full extension and immobilization of the extremity for 6 to 8 weeks postoperatively to allow for graft healing. Nonsurgical management will not result in an acceptable outcome for a young patient, and attempted secondary repair is associated with a high rate of failure, even when augmented with local tissues. This patient has gross rotational
malalignment of the components and the surgeon faced with this problem should consider obtaining a CT scan to determine component rotation preoperatively.

REFERENCES: Burnett RS, Berger RA, Paprosky WG, et al: Extensor mechanism allograft reconstruction after total knee arthroplasty: A comparison of two techniques. J Bone Joint Surg Am 2004;86:2694-2699.
Nazarian DG, Booth RE: Extensor mechanism allografts in total knee arthroplasty. Clin Orthop Relat Res
1999;367-123-129. , „. H
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Figure 53

The muscle-tendon unit exerts a protective effect on cortical bone by acting as the major shock absorber. With muscle contraction, cortical bone surface bending strains are reduced. In most weight-bearing bones it is believed that with muscle fatigue, the shock-absorbing effect is lessened and more force is transmitted directly to bone, increasing the likelihood of microdamage accumulation

Neutral abduction is important in preventing back pain.
The flexion should be between 25° and 35°.
Any abduction beyond neutral poses increased risk of back pain. External rotation beyond approximately 5° is not needed.
Arthrodesis often produces some shortening; therefore, intentional shortening is not needed.

Trials comparing the results of open repair of acute Achilles tendon rupture to repairs done in a limited open fashion show no difference in rerupture rate, sural neuropathy, or calf circumference.The scarring observed was much less in the group treated in a limited open fashion. There was a significantly greater number of postoperative complications seen in the group treated in an open fashion compared with those treated with a limited open procedure.

Acetabular screws are commonly used to stabilize the acetabular component. This is particularly true in revision surgery. Wasielewski and associates described a quadrant system for placing screws, and the safest quadrants for screw placement are the posterior superior and posterior inferior quadrants. Placement of screws in the anterior superior quadrant is particularly dangerous because the screws may damage the external iliac artery or vein.
The femoral artery is more anterior and distal and less likely to be damaged by screw placement. The superior and inferior gluteal arteries may be injured but are less likely to be affected by screw placement anteriorly and are more likely to be noted immediately.
RECOMMENDED READINGS
5. Wasielewski RC, Cooperstein LA, Kruger MP, Rubash HE. Acetabular anatomy and the transacetabular fixation of screws in total hip arthroplasty. J Bone Joint Surg Am. 1990 Apr;72(4):501-
[8/. PubMed PMID: 2324135. ](http://www.ncbi.nlm.nih.gov/pubmed/2324135)[View Abstract at PubMed](http://www.ncbi.nlm.nih.gov/pubmed/2324135)
6. [Wasielewski RC, Crossett LS, Rubash HE. Neural and vascular injury in total hip arthroplasty. Orthop Clin North Am. 1992 Apr;23(2):219-35. Review. PubMed PMID: 1315014. ](http://www.ncbi.nlm.nih.gov/pubmed/1315014)[View Abstract ](http://www.ncbi.nlm.nih.gov/pubmed/1315014)[at PubMed](http://www.ncbi.nlm.nih.gov/pubmed/1315014)

The clinical description and MR image point to an injury to the posterior cruciate ligament (PCL). This ligament is thought to be primarily composed of anterolateral and posteromedial bundles, with the former tightening in flexion and the latter in extension. Because of alterations in knee kinematics and increased varus alignment in PCL insufficiency, contact stresses and cartilage loads increase in the patellofemoral and medial compartments. Although good outcomes may be obtained with transtibial, open inlay, and arthroscopic inlay techniques, one major difference is the creation of the “killer-turn” during the transtibial approach. This sharp turn in the graft as it emerges from the tibia appears to lead to more pronounced attenuation and thinning of the graft during cyclic loading. The scenario describes a patient with chronic PCL and posterolateral corner (PLC) injury, as evidenced by the varus thrust and abnormal Dial test finding. A valgus-producing osteotomy may be effective, and, in fact, may be the only treatment necessary to address chronic PLC injury. Accordingly, an opening lateral osteotomy would not be appropriate. Of the remaining responses, an osteotomy that increases tibial slope would also address the PCL deficiency by reducing posterior tibial sag. Vascular injury is an uncommon, but potentially devastating, complication associated with PCL surgery and may occur regardless of the technique used.
Numerous strategies have been described to reduce the risk, including use of a posteromedial accessory incision to allow finger retraction of the popliteal neurovascular bundle, oscillating drills to prevent excessive soft-tissue entanglement, and tapered (rather than square) drill bits that may minimize cut-out of sharp edges as drilling reaches the posterior tibial cortex. Knee extension lessens, rather than increases, the distance between the posterior tibia and the neurovascular bundle and increases, not lessens, risk for _vascular injury._

This patient had an eccentric muscle contraction (muscle lengthening while contracting) of his biceps muscle while trying to stop a defender from getting around him. This in turn caused failure of the distal biceps tendon, as evidenced by pain in the antecubital fossa, lack of elbow supination strength, and his positive biceps active test finding (supination/pronation of the forearm showing no motion of the biceps muscle belly). Eccentric contractors have the highest potential for building strength but also are at highest risk for injury. Concentric (muscle shortening with contraction), isometric (no change in muscle length with contracture), and isokinetic (constant velocity of muscle contraction with a variable force) do not describe the mechanism detailed. The loss of distal biceps attachment will result in loss of elbow supination strength in flexion (the biceps is the only supinator to cross the elbow) while still retaining elbow flexion (albeit weakened) because of the other elbow flexors (brachioradialis and brachialis). Consequently, treatment should be anatomic repair of the distal biceps insertion, which can be performed with a 2-incision or 1-incision technique. Although all of the listed complications have been reported with these techniques, LABC neuropraxia is by far the most common. Radiographs show that this athlete’s injury was repaired using a 1-incision technique with a cortical fixation device and a radial bone tunnel. This technique has gained favor because of its decreased incidence of heterotopic ossification and radioulnar synostosis compared with the 2-incision technique. The most troubling complication for most surgeons is the development of a posterior interosseous nerve (PIN) palsy, which this patient clearly demonstrates in addition to the more common LABCN upon postsurgical examination. Because the LABCN injury is typically a neuropraxia from retraction, a period of observation is indicated. PIN injury can result from excessive traction during surgical exposure or from entrapment by the fixation button. Considering the anatomy of the PIN, successful recovery of the nerve typically progresses based on the distance from the origin of the nerve to the muscle indicated. The extensor indicis proprius (EIP) muscle is the most distal muscle innervated and can be expected to recover last. First to return would be the EDC
followed by the ECU, EDQ, and, finally, the EIP.