OITE & ABOS Orthopedic MCQs: Hip Arthroplasty Pt 242

About This Board Review Set

This is Part 242 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.

How to Use the Interactive Quiz

Two distinct learning modes are available:

Study Mode — After selecting an answer, you immediately see whether you are correct or incorrect, together with a full clinical explanation and literature references.
Exam Mode — All feedback is hidden until you click Submit & See Results. A live timer tracks elapsed time. A percentage score and detailed breakdown are displayed upon submission.

Pro Tip: Use keyboard shortcuts A–E to select options, F to flag a question for review, and Enter to jump to the next unanswered question.

Topics Covered in Part 242

This module focuses heavily on: Arthroplasty, Dislocation, Fracture, Hip, Revision.

Sample Questions from This Set

Sample Question 1: Two years ago, a 63-year-old man underwent right total hip arthroplasty (THA) with a modular femoral head-neck and neck-stem prosthesis (a photograph of the removed implantis shown in Figure 181). He now has increasing hip pain. Radiographs...

Sample Question 2: Bioabsorbable polymers are used in a wide range of orthopaedic devices, including anchors, staples, pins, plates, and screws. What is the primary drawback for bioabsorbable implants?...

Sample Question 3: In revision total hip arthroplasty, an acetabular reconstruction cage is best indicated for which of the following patterns of bone loss?...

Sample Question 4: In an effort to reduce costs, a limited MRI sequence is planned to detect a possible occult hip fracture. What is the anticipated fracture signal?...

Sample Question 5: What type of injury is considered the major mechanism of cervical fracture, dislocation, and quadriplegia in contact sports and diving?...

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

00:00

Start Quiz

Question 1

Two years ago, a 63-year-old man underwent right total hip arthroplasty (THA) with a modular femoral head-neck and neck-stem prosthesis (a photograph of the removed implant is shown in Figure 181). He now has increasing hip pain. Radiographs reveal a stable hip arthroplasty and elevated serum cobalt and chromium levels. MR imaging is obtained, and, based on these findings, the patient’s hip is revised. Which corrosion type likely is responsible for this THA failure?

Explanation

DISCUSSION
Micromotion at the femoral head-neck or stem-neck junction can lead to fretting corrosion. Fretting corrosion is among the most common causes of failure in modular components. Modularity gives surgeons additional intraoperative flexibility but has resulted in corrosion-related failure and an implant recall. Although titanium and cobalt-chrome contain a protective surface oxide layer, continued micromotion at the modular junction may disrupt the protective layer, resulting in fretting corrosion. This may eventually lead to excessive metal ion formation and painful synovitis that necessitates a revision procedure. Galvanic corrosion is attributable to a mismatch in electrochemical gradients between dissimilar metals. Crevice or pitting corrosion occurs in fatigue cracks because of differences in oxygen tension.

Question 2

Bioabsorbable polymers are used in a wide range of orthopaedic devices, including anchors, staples, pins, plates, and screws. What is the primary drawback for bioabsorbable implants?

Explanation

DISCUSSION: A number of bioabsorbable polymers are used in orthopaedic applications, and all have in common reports of foreign body reactions, which occur in more than 50% of patients in some series. In general, the high cost of these polymers is offset by the elimination of a second surgery to remove the implant. Bioabsorbable polymers are low strength in comparison to metallic alloys but of sufficient strength for many orthopaedic applications. The elastic modulus is not as high as many other orthopaedic biomaterials, making them suitable for applications where lower stiffness is an asset.
REFERENCES: Ambrose CG, Clanton TO: Bioabsorbable implants: Review of clinical experience in orthopedic surgery. Ann Biomed Eng 2004;32:171-177.
Bergsma JE, de Bruijn WC, Rozema FR, et al: Late degradation tissue response to poly

(L-lactide) bone plates and screws. Biomaterials 1995;16:25-31.

Question 3

In revision total hip arthroplasty, an acetabular reconstruction cage is best indicated for which of the following patterns of bone loss?

Explanation

DISCUSSION: Acetabular cage reconstruction is indicated in severe disruption of acetabular bone stock when a cementless acetabular component cannot be stabilized in intimate contact with a sufficient bed of structurally sound and viable host bone, with or without a structural graft. Cages are used in pelvic discontinuity where they provide a bridge between the ilium and the ischium, while supporting a cemented cup. All of the other scenarios are amenable to achieving an adequate rim fit for a cementless component, using a jumbo cup if necessary.
REFERENCES: Whiteside LA: Selection of acetabular component, in Steinberg ME, Garino JP (eds): Revision Total Hip Arthroplasty. Philadelphia, PA, Lippincott Williams and Wilkins, 1999, pp 209-220.
Berry DJ, Muller ME: Revision arthroplasty using an anti-protrusio cage for massive acetabular bone deficiency. J Bone Joint Surg Br 1992;74:711-715.

Question 4

In an effort to reduce costs, a limited MRI sequence is planned to detect a possible occult hip fracture. What is the anticipated fracture signal?

Explanation

DISCUSSION: At present, radiologists perform multiple MRI images to rule out all possible diagnoses. The ability to specify the anticipated changes on MRI should become more important as a means of reducing costs. MRI is sensitive to changes in free water (or hemorrhage) and thus this will appear dark on T₁ and bright on T₂.
REFERENCES: Miller MD: Review of Orthopaedics, ed 3. Philadelphia PA, WB Saunders, 2000, p 116.
Guanche CA, Kozin SH, Levy AS, et al: The use of MRI in the diagnosis of occult hip fractures in the elderly: A preliminary review. Orthopedics 1994;17:327-330.

Question 5

What type of injury is considered the major mechanism of cervical fracture, dislocation, and quadriplegia in contact sports and diving?

Explanation

DISCUSSION: A compression or burst injury occurs with vertical loading of the spine, such as from a blow to the vertex with the neck flexed (eg, spear tackling in football). This leads to vertebral end plate fractures before disk injury. At higher forces, the entire vertebra and disk may explode into the spinal canal. Analysis has shown this to be the major mechanism of cervical fracture, dislocation, and quadriplegia. With the normal head-up posture, the cervical spine has a gentle lordotic curve, and forces transmitted to the head are largely dissipated in the cervical muscles. When the neck is flexed, the cervical spine becomes straight, with the vertebral bodies lined up under one another. This allows for minimal dissipation of the impact forces to be absorbed by the neck muscles.
REFERENCES: Cantu RC: Head and spine injuries in youth sports. Clin Sports Med 1995;14:517-532.
Proctor MR, Cantu RC: Head and neck injuries in young athletes. Clin Sports Med 2000;19:693-715.
Torg JS: Epidemiology, pathomechanics, and prevention of athletic injuries to the cervical spine. Med Sci Sports Exerc 1985;17:295-303.

Question 6

A 14-year-old patient who has homocystinuria and is Risser 3 is referred for surgical treatment of scoliosis. In addition to the usual risks associated with posterior spinal fusion, the family should be advised that the patient ‘s underlying condition significantly increases the perioperative risk of

Explanation

Tendency towards venous and arterial thrombosis along with mental retardation, dislocation of the lens and skeletal changes resembling Marfan’s are all clinical features of homocystinuria. Homocysteine is toxic and causes endothelial cell damage. Increased platelet stickiness is also associated with the disease.
1 and 2 are concerns during spinal fusion but are not specific to this disease. 4 may occur with homocystinuria but is not related to spinal fusion. 5 occurs with PSF in the younger population because of the growth potential remaining.

Question 7

A 68-year-old woman underwent a successful total right hip arthroplasty with a metal-on-metal articulation and cementless porous-coated components. Three months later, she underwent identical surgery on the left hip. Three months after surgery on the left hip, she reports groin pain on ambulation. Examination reveals significant groin discomfort with passive hip motion, particularly at the extremes of motion. Radiographs are shown in Figures 21a and 21b. Laboratory studies show an erythrocyte sedimentation rate of 35 mm/h and a C-reactive protein of 0.9. Aspiration yields scant growth of Staphylococcus epidermidis in the broth only, with no evidence of loosening on arthrography. A second aspiration yields scant growth of Staphylococcus epidermidis in the broth only. What is the most likely cause of the patient’s pain?

Explanation

DISCUSSION: The difference in the clinical results combined with the laboratory findings points to infection. While there is a significant risk of false-positive findings with aspiration, the fact that two successive aspirations grew the same organism strongly suggests infection. The radiograph shows that there is more radiolucency around the left acetabular component than the right component.
REFERENCES: White RE: Evaluation of the painful total hip arthroplasty, in Callaghan JJ, Rosenberg AG, Rubash HE (eds): The Adult Hip. Philadelphia, PA, Lippincott-Raven, 1998,

vol 2, pp 1377-1385.
Barrack RL, Harris WH: The value of aspiration of the hip joint before revision total hip arthroplasty. J Bone Joint Surg Am 1993;75:66-76.

Question 8

A 65 year-old female presents to your clinic with a chief complaint of difficulty walking. She states that she has had low back pain and balance difficulties for the last 2 years, but over the last few months new bilateral posterior thigh and buttock pain has prevented her from walking more than 100 feet. She states the only place she can walk comfortably is in the grocery store. On physical exam she is unable to preform a tandem gait, and she has 5/5 strength with hip flexion, knee flexion/extension, ankle dorsiflexion/plantar flexion and great toe extension. Her sensation is intact in L2-S2, and she has equal and symmetric 3+ achilles and patellar reflexes. She has 8 beats of clonus, and a down-going Babinski reflex bilaterally.

Explanation

The patient has signs and symptoms of both lumbar spinal stenosis and myelopathy, also known as tandem stenosis. The next most appropriate step is a cervical spine MRI.
While 79% of patients with cervical myelopathy will have at least one sign on physical exam, the absence of a one or more signs such as a Babinski reflex or a Hoffman's sign does not rule out the diagnosis of myelopathy. Tandem cervical and lumbar stenosis occurs in between 5 and 25% of patients with lumbar stenosis, and because of the stepwise progressive nature of myelopathy, it is critical not to miss this diagnosis.
Rhee et al. found that the sensitivity and specificity of specific physical exam findings varies in patients with myelopathy. Overall 79% of patients will have at least one physical exam sign of myelopathy, with biceps hyperreflexia (62%) and the Hoffman sign (59%) being the most sensitive. Classic upper motor neuron findings in the lower extremity such as an upward Babinski reflex (13%) and clonus (13%) are not sensitive.
Lee et al. performed a cadaveric study of 440 specimens to identify the overall prevalence of stenosis in the population. They found 5.4% of the specimens had cervical stenosis and 5.9% had lumbar stenosis. A total of 0.9% had both cervical and lumbar stenosis.
Bajwa et al. evaluated over 1,000 skeletal remains to determine if tandem stenosis (concomitant lumbar and cervical stenosis) is due to an increased risk of disc degeneration or a congenitally small vertebral canal, and they concluded that tandem stenosis is likely due to a congenitally small vertebral canal in both the cervical and lumbar spine.
Figure A and B demonstrate an AP and lateral radiograph of the lumbar spine respectively. A degenerative L4/5 spondylolisthesis is present.
Incorrect answers:

Question 9

A 28-year-old man sustained numerous injuries in an accident including a dislocation of the elbow and a severe closed head injury that resulted in unconsciousness. The elbow was reduced in the emergency department. After 1 month of rehabilitation, the patient reports pain and stiffness. A radiograph is shown in Figure 23. Management should now consist of

Explanation

DISCUSSION: In a young individual with a chronic dislocation of the elbow and heterotopic bone formation, the treatment of choice is open reduction, heterotopic bone excision, anterior and posterior capsular releases, and a dynamic hinged fixator to begin protected early postoperative range of motion. It is important to understand that the fixator protects the reconstruction and allows early range of motion, but it does not maintain the reduction and should not be expected to do so. Pin fixation across the elbow delays early motion and is not recommended. Total elbow arthroplasty is not indicated, and ulnohumeral arthroplasty is for a primary arthritic condition.
REFERENCES: Garland DE, Hanscom DA, Keenan MA, et al: Resection of heterotopic ossification in the adult with head trauma. J Bone Joint Surg Am 1985;67:1261-1269.
Moor TJ: Functional outcome following surgical excision of heterotopic ossification in patients with traumatic brain injury. J Orthop Trauma 1993;7:11-14.

Question 10

Figure 36 shows the radiograph of a patient who has hip pain and is unable to ambulate. What is the most appropriate management for this patient?

Explanation

DISCUSSION: The patient has a periprosthetic fracture of the greater trochanter - Vancouver A. The reason for the fracture of the greater trochanter is the extensive periarticular osteolysis that has occurred as a result of polyethylene wear. The latter is demonstrated by eccentric seating of the large femoral head in the acetabulum. The most appropriate management is to reverse the osteolysis process, which involves exchange of the acetabular liner with or without revision of the other components depending on their fixation and position. The greater trochanter can also be fixed during revision surgery.
REFERENCES: Duncan CP, Masri BA: Fractures of the femur after hip replacement. Instr Course Lect 1995;44:293-304.
Parvizi J, Rapuri VR, Purtill JJ, et al: Treatment protocol proximal femoral periprosthetic fractures. J Bone Joint Surg Am 2004;86:8-16.

Question 11

Figures 2a and 2b show the radiographs of a 72-year-old man with aseptic loosening of the tibial component of his total knee arthroplasty. Optimal management should include

Explanation

DISCUSSION: The radiographs show massive subsidence of the lateral side of the tibia with severe tibial bone loss and a fractured proximal fibula. Reconstruction should consist of a large metal or bony lateral tibial augmentation, and a stem long enough to bypass the defect is required. The femoral and tibial components are articulating without any remaining polyethylene medially; therefore, the femoral component is damaged and needs revision.

The insertions of the lateral ligaments are absent, thereby rendering the lateral side of the knee predictably unstable. Also, the large valgus deformity compromises the medial collateral ligament. The posterior cruciate ligament is also likely to be deficient with this much tibial bone destruction. The patient requires a posterior stabilized femoral component at the minimum, and possibly a constrained femoral component. Retention of the femoral component, even though it may be well-fixed, jeopardizes the outcome.
REFERENCES: Lotke PA, Garino JP: Revision Total Knee Arthroplasty. New York, NY, Lippincott-Raven, 1999, pp 137-250.
Insall JN, Windsor RE, Scott WN, et al: (eds): Surgery of the Knee, ed 2. New York, NY, Churchill Livingstone, 1993, pp 935-957.
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 339-365.

Question 12

A 14-year-old girl has had progressive heel pain for the past several months. Based on the radiograph, MRI scan, and biopsy specimens shown in Figures 37a through 37d, treatment should include

Explanation

DISCUSSION: An aneurysmal bone cyst is a benign, locally destructive lesion of bone. Most are seen in patients in the second decade of life. The clinical presentation varies, but most patients have pain, tenderness, swelling, and/or pathologic fracture. Radiographs show a radiolucent lesion sometimes with expansile remodeling of the cortex. MRI best detects the commonly seen fluid-fluid levels associated with this lesion. Histologic findings include

blood-filled spaces with bland fibrous connective tissue septa. The stroma has histiocytes, fibroblasts, scattered giant cells, hemosiderin, and occasional inflammatory cells. Treatment of these lesions consists of extended curettage, plus or minus the use of adjuvants (liquid nitrogen, phenol, argon beam coagulation), and finally filling the bone void (allograft or other bone substitute).
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.
Ramirez AR, Stanton RP: Aneurysmal bone cyst in 29 children. J Pediatr Orthop 2002;22:533-539.

Question 13

A 21-year-old woman with Marfan syndrome is seeking evaluation of her scoliosis. She reports no back or leg pain, and the neurologic examination is normal. Lateral and bending radiographs are shown in Figures 7a through 7e. Management should consist of

Explanation

DISCUSSION: Because the patient’s thoracolumbar scoliosis is of a large enough magnitude, observation or bracing is not recommended. The thoracolumbar curve is flexible enough and L4 corrects well enough to the pelvis to consider anterior spinal fusion from T10 to L4.
REFERENCES: Garfin SR, Vaccaro AR (eds): Orthopaedic Knowledge Update: Spine. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1997, pp 161-171.
Turi M, Johnston CE II, Richards BS: Anterior correction of idiopathic scoliosis using TSRH instrumentation. Spine 1993;18:417-422.
Moskowitz A, Trommanhauser S: Surgical and clinical results of scoliosis surgery using Zielke instrumentation. Spine 1993;18:2444-2451.

Question 14

Which lower extremity muscle is first weakened in Charcot-Marie-Tooth (CMT) disease?

Explanation

DISCUSSION
Although many of the lower extremity muscles may be affected in CMT, those innervated by the longest axons have been shown to be affected first. In the lower extremity the muscles innervated by the longest axons are the intrinsic foot muscles. The tibialis anterior and the peroneus brevis may be severely affected but not before the foot intrinsics. The peroneus longus typically is spared, resulting in the cavus.
RECOMMENDED READINGS
Pareyson D, Marchesi C. Diagnosis, natural history, and management of Charcot-Marie-Tooth disease. Lancet Neurol. 2009 Jul;8(7):654-67. Review. PubMed PMID: 19539237. View Abstract at PubMed
Wenz W, Dreher T. Charcot-Marie-Tooth disease and the cavovarus foot. In: Pinzur MS, ed. Orthopaedic Knowledge Update: Foot and Ankle 4. Rosemont, IL: American Academy of Orthopaedic Surgeons; 2008:291-306.
CLINICAL SITUATION FOR QUESTIONS 60 THROUGH 63
Figure 60 is the standing radiograph of a 27-year-old man who played football throughout his teen years. During those years, he noted that he had less mobility of his left foot and ankle. He twisted his left foot and ankle 8 months ago and has tried over-the-counter nonsteroidal anti-inflammatory drugs and a brace. He now has pain and edema in the left sinus tarsi area. Upon examination the following arcs of motion are identified: ankle dorsiflexion-right, 5 degrees/left, 5 degrees; ankle plantar flexion-right, 30 degrees/left 30 degrees; foot inversion-right, 10 degrees/left, 5 degrees; foot eversion-right, 10 degrees/left 5 degrees.

Question 15

A 32-year-old woman has had pain and a visibly growing mass in the shoulder for 3 years but denies any history of trauma. Examination reveals a swollen, boggy shoulder mass. The AP radiograph and MRI scan are shown in Figures 20a and 20b. Figures 20c through 20e show a portion of the excised mass and the photomicrographs of the biopsy specimen. What is the most likely diagnosis?

Explanation

DISCUSSION: The radiographic findings are classic for synovial chondromatosis because of the small calcified opacities within the joint surrounding the synovium. The histologic findings show cartilaginous foci of metaplasia, which may be markedly cellular. However, unlike low-grade chondrosarcoma, it lacks cellular and nuclear pleomorphism.
REFERENCES: Murphy FP, Dahlin DC, Sullivan CR: Articular synovial chondromatosis. J Bone Joint Surg Am 1982;44:77-86.
Milgram JW: Synovial osteochondromatosis: A histopathological study of thirty cases. J Bone Joint Surg Am 1977;59:792-801.

Question 16

During a posterior cruciate ligament (PCL)-retaining total knee arthroplasty, a critical principle to remember is to

Explanation

DISCUSSION:
Maintenance of the joint line and accurately tensioning the PCL are critical in the proper execution of a PCL-retaining total knee arthroplasty. Appropriate tension helps ensure femoral rollback and avoid stiffness or instability. Raising the joint line to help ensure full extension should be avoided in cruciate-retaining knees, because doing so creates an unfavorable kinematic environment. The three important principles of surgical technique needed to maintain appropriate tensioning of the PCL include 1) choosing the proper femur size to reproduce the native femoral anterior/posterior dimension, 2) reproducing the joint line by resecting as much tibia from the healthy side as will be replaced by the smallest thickness of the tibial component and, 3) ensuring that full extension is achieved by soft-tissue releases and not by taking additional distal femur, as may be done in a posterior stabilized approach. Another important principle is to re-create the natural degree of the patient’s posterior tibial slope to avoid tightness in flexion.

Question 17

Treatment of this fracture should consist of

Explanation

DISCUSSION
Varus posteromedial rotatory instability is a complex injury pattern that starts with varus stress resulting in a fracture of the anteromedial coronoid. The anterior MCL attaches to the sublime tubercle, which is part of the anteromedial coronoid facet. The posterior MCL attaches to the posterior medial aspect of the ulna. The radial collateral and lateral ulnar collateral attach to the ulna at the crista supinatoris. The bony landmark is the sublime tubercle; as noted above, the crista supinatoris is lateral on the ulna. The radial notch is also lateral and is the articulation between the proximal ulna and proximal radius. The anteromedial coronoid facet is part of the coronoid, which extends more lateral and anterior than the anteromedial facet. The anteromedial facet represents the critical weight-bearing portion of the ulnohumeral joint. Damage to this structure causes posteromedial subluxation that often results in severe progressive arthritis. The coronoid is the larger structure of which the anteromedial coronoid facet is a portion. The posteromedial coronoid facet does not appear to be critical in weight bearing. The radial notch is not associated with increased stress with weight bearing. The treatment of displaced fractures of this structure is open reduction and internal fixation utilizing buttress plating. Closed treatment is acceptable only for nondisplaced fractures with appropriate radiographic follow-up. Suture fixation is not advocated because of inadequate strength.
RECOMMENDED READINGS
Pollock JW, Brownhill J, Ferreira L, McDonald CP, Johnson J, King G. The effect of anteromedial facet fractures of the coronoid and lateral collateral ligament injury on elbow stability and kinematics. J Bone Joint Surg Am. 2009 Jun;91(6):1448-58. doi: 10.2106/JBJS.H.00222.
Sanchez-Sotelo J, O'Driscoll SW, Morrey BF. Anteromedial fracture of the coronoid process of the ulna. J Shoulder Elbow Surg. 2006 Sep-Oct;15(5):e5-8. Epub 2006 Jul 26. Erratum in: J Shoulder Elbow Surg. 2007 Jan-Feb;16(1):127. PubMed PMID: 16979044.

Question 18

Which of the following methods is effective in correcting recurrent dislocation following total hip arthroplasty?

Explanation

DISCUSSION: Recurrent dislocation following total hip arthroplasty is a difficult problem to correct. Studies conducted by the Mayo Clinic show a failure rate of close to 40% with surgical treatment. A variety of methods have been successful, but no specific approach has been reported to be the most predictably successful. To select and institute the proper treatment option, the cause of the dislocation must be identified. Surgical options fall into several broad categories that include increasing soft-tissue tension (trochanteric advancement or longer neck lengths) or more stable articulation (larger diameter head component, bipolar prosthesis, or a constrained component). In a series of total hip arthroplasties done with a constrained cup, the loosening rates of the cup and the stem were reported to be 6% each, comparable to a reported series of complex revision total hip arthroplasties at a similar follow-up interval.
REFERENCES: Woo RY, Morrey BF: Dislocations after total hip arthroplasty. J Bone Joint Surg Am 1982;64:1295-1306.
Goetz DD, Capello WN, Callaghan JJ, Brown TD, Johnston RC: Salvage of a recurrently dislocating total hip prosthesis with use of a constrained acetabular component: A retrospective analysis of fifty-six cases. J Bone Joint Surg Am 1998;80:502-509.

Question 19

A 9-year-old girl has pain over the fifth toe that is aggravated by shoe wear. Clinical photographs are shown in Figures 28a and 28b. Treatment of this deformity should consist of

Explanation

DISCUSSION: The major obstacle to overcome in the surgical treatment of this cock-up deformity is recurrence. Dorsal releases can be performed; however, chronic dislocation of the fifth MTP joint usually needs to be addressed with plantar release as well. Chronic dorsal soft-tissue contractures may be overcome with translation of the toe into a plantar-based incision, as described originally by Cockin and accredited to Butler. This is the treatment of choice. Resection of the proximal phalanx improves symptoms but induces a secondary deformity; this procedure is usually reserved for skeletally mature individuals.
REFERENCES: Black GB, Grogan DP, Bobechko WP: Butler arthroplasty for correction of adducted fifth toe: A retrospective study of 36 operations between 1968 and 1982. J Pediatr Orthop 1985;5:439-441.
Paton RW: V-Y plasty for correction of varus fifth toe. J Pediatr Orthop 1990;10:248-249.
Coughlin MJ, Mann RA: Lesser toe deformities, in Coughlin MJ, Mann RA (eds): Surgery of the Foot and Ankle, ed 5. St Louis, MO, Mosby, 1986, pp 132-157.

Question 20

A 64-year-old woman sustains a fracture to her distal femur 5 years after undergoing total knee arthroplasty. When choosing between locked femoral plating and retrograde femoral nailing, which factor is important to consider based on this patient’s surgical record?

Explanation

CLINICAL SITUATION FOR QUESTIONS 128 THROUGH 130
Figure 128 is the radiograph of a 78-year-old nursing home resident who has hypertension and peripheral vascular disease. He has developed acute severe hip pain 20 years after undergoing a cementless total hip arthroplasty (THA) and subsequent revision for instability. He was previously ambulatory with a walker and now can no longer ambulate. His erythrocyte sedimentation rate is 8 mm/h (reference range [rr], 0-20 mm/h) and C-reactive protein level is

Question 21

Suprapatellar intramedullary nailing for tibia fractures when compared to infrapatellar nailing is associated with

Explanation

Discussion: Suprapatellar nailing has been very useful in the management of proximal tibia fractures, allowing a better reduction. Both arthroscopy and MRI have been utilized after suprapatellar nailing to evaluate for changes in the patellofemoral joints, and no significant changes can be attributed to this technique. In a comparative study between suprapatellar nailing and standard (infrapatellar) nailing, both techniques showed excellent range of motion and no significant differences between the methods. In a separate study, it was noted that patients who underwent suprapatellar nailing did not complain of anterior knee pain that is often seen with standard nailing.

Question 22

Radiographs of a pediatric patient reveal a suspected osteosarcoma of the distal femur. Additional staging studies should consist of

Explanation

DISCUSSION: CT of the abdomen and pelvis is not part of the staging of osteosarcoma. Staging studies should consist of CT of the chest, radiographs of the chest and primary tumor, MRI of the primary tumor, and a bone scan. The MRI should be obtained prior to the biopsy.
REFERENCE: O’Reilly R, Link M, Fletcher B, et al: NCCN pediatric osteosarcoma practice guidelines: The National Comprehensive Cancer Network. Oncology (Huntingt) 1996;10:1799-1806, 1812.

Question 23

Staged open reduction and internal fixation with free flap soft tissue reconstruction is the most appropriate definitive treatment method for which of the following tibial injuries?

Explanation

DISCUSSION: By definition, with Type IIIB injuries, there is exposed bone after debridement which will require a local or a free flap for coverage. Distal third IIIB tibial shaft fracture are unique in that they usually require a free flap or reverse sural rotational flap to obtain adequate coverage. As stated in Skeletal Trauma, "As local donor muscles in the distal third of the tibia are almost non-existent, closure of an open plafond fracture, or any extensive Type IIIB injury in this area will usually require free tissue transfer. The primary options are latissimus dorsi or rectus abdominus for large defects, and gracilis for smaller wounds." In addition to the flaps mentioned here, others, including fasciocutaneous flaps and radial forearm flaps, are also utilized with success in this area.
Typically, treatment of Type IIIB tibial shaft fractures should be staged. Initially tetanus prophylaxis, antibiotics with gram negative and positive coverage, and application of an external fixator with repeat I&D’s are employed for immediate fracture care. Plating is usually required in the presence of significant intra-articular fracture involvement.
Incorrect Answers: Typically, proximal third tibia fractures requiring soft tissue coverage can be treated with a gastrocnemius rotation flap and middle third tibia fractures with soft tissue defects can be reliably covered with a soleus rotation flap. Therefore, a free flap is rarely indicated in the proximal and middle tibia.

Question 24

A 55-year-old woman with a history of untreated idiopathic scoliosis has had neurogenic claudication for the past several months. MRI reveals spinal stenosis at L2-L3, L3-L4, and L4-L5. Radiographs show a 45° lumbar curve from T10 to L4, with a degenerative spondylolisthesis at L4-L5. Laminectomy at the stenotic levels and stabilization of the deformity are planned. Which of the following is NOT considered an absolute indication for extending the fusion to the sacrum, rather than stopping at L5?

Explanation

DISCUSSION: There are several indications for extending adult scoliosis fusions to the sacrum, rather than stopping in the lower lumbar spine. These indications include posterior column deficiencies at L5-S1, such as spondylolysis and laminectomy, and deformities extending to the sacrum, such as fixed tilt of L5-S1 or sagittal imbalance. MRI signal changes in the L5-S1 disk do not preclude stopping the fusion at L5. Some surgeons use diskography or diagnostic facet blocks to evaluate the integrity of the L5-S1 level prior to stopping the fusion at L5. Long scoliosis fusions stopping at L5 have a significant risk of failure, highlighting the importance of careful selection of fusion levels.
REFERENCES: Bradford DS, Tay BK, Hu SS: Adult scoliosis: Surgical indications, operative management, complications, and outcomes. Spine 1999;24:2617-2629.
Bridwell KH: Where to stop the fusion distally in adult scoliosis: L4, L5, or the sacrum? Instr Course Lect 1996;45:101-107.
Edwards CC II, Bridwell KH, Patel A, et al: Long adult deformity fusions to L5 and the sacrum: A matched cohort analysis. Spine 2004;29:1996-2005.

Question 25

When performing a gastrocnemius recession, what structure should be protected?

Explanation

DISCUSSION: When performing a gastrocnemius slide at the tendinous portion of the gastrocnemius insertion, the sural nerve and saphenous vein, which tend to run midline posterior at this level, must be protected and retracted laterally. An anatomic study of the sural nerve at this level localized the nerve superficial to the deep fascia overlying the gastrocnemius in 42.5% of the cases; deep to the superficial fascia in 57.5% of the cases, and directly applied to the gastrocnemius tendon in 12.5% of cases.
REFERENCES: Pinney SJ, Sangeorzan BJ, Hanen ST Jr: Surgical anatomy of the gastrocnemius resection (Strayer procedure). Foot Ankle Int 2004;25:247-250.
Hansen ST Jr: Functional Reconstruction of the Foot and Ankle. Philadelphia, PA, Lippincott Williams & Wilkins, 2000, pp 415-417.

Question 26

Figures 33a and 33b show the standing posteroanterior and lateral radiographs of a 59-year-old woman with adult idiopathic scoliosis. She underwent a prior decompressive laminectomy and fusion at L4-S1 to address lumbar stenosis. She now reports progressive lower back pain and a feeling of being shifted to the right. If surgical intervention is considered, what is the most important goal in improving her health-related quality of life (HRQL) outcomes? Review Topic

Explanation

Nonoperative management with NSAIDS and physical therapy is effective for 50% of patients
Surgical treatment is indicated in patients with diminished sensation
Surgical treatment is equivalent to nonoperative management in terms of pain and function
Good surgical outcome is associated with mainly back complaints
Size of disc herniations typically decrease over time without surgical intervention
The patient is presenting with a lumbar disc herniation at the L4-L5 level. The size of disc herniations decrease in most patients over time without surgical intervention.
Lumbar disc herniations are the result of recurrent torsional strain, which leads to small tears of the annulus fibrosus, ultimately allowing herniation of the nucleus pulposis. First line treatment consists of NSAIDS, muscle relaxants and physical therapy and is effective in 90% of patients. Second line treatment typically involves epidural and selective nerve root corticosteroid injections. Microdiscectomy is reserved for patients with more than 6 weeks of disabling pain that has failed nonoperative management, progressive weakness, or cauda equina syndrome.
In the Spine Patient Outcomes Research Trial (SPORT), Weinstein et al. investigated patient outcomes and satisfaction after operative and nonoperative management of lumbar disc herniations. While the randomized arm of the study did show statistically significant differences in the intent-to-treat analysis due to significant crossover of patients, the observational cohort revealed a significant improvement in pain, function, and disability for patients treated with surgery versus nonoperative measures.
Benson et al. looked at the natural history of massive herniated discs in 37 patients with 7-year follow up. They found a more than 60% reduction in disc size over this time period. Reduction in disc size did not correlate with clinical improvement.
Figure A and B are sagittal and axial T2 MRI images, respectively, showing a right sided lumbar disc herniation at the L4-L5 level.
Incorrect Answers:

Question 27

A 22-year-old college football player reports shortness of breath and dyspnea after a tackle. Examination reveals tachypnea, tachycardia, the trachea is shifted to the right, and there are decreased breath sounds on the left lung fields. The first line of treatment on the field should be

Explanation

DISCUSSION: The patient has a tension pneumothorax. This is a life-threatening emergency where air is trapped between the pleura and the lung, which prevents expansion of the lung. This causes hypoxia and cardiopulmonary compromise. The first line of treatment is to place a needle into the second intercostal space in the midclavicular line. The athlete should then be transported to the emergency department for chest tube placement. The athlete cannot return to play, and resuscitation is not necessary because he has not gone into cardiopulmonary arrest.
REFERENCES: Amaral JF: Thoracoabdominal injuries in the athlete. Clin Sports Med 1997;16:739-753.
Perron AD: Chest pain in athletes. Clin Sports Med 2003;22:37-50.

Question 28

Regarding the role of the orthopaedic surgeon in addressing domestic and family violence, all of the following statements are true EXCEPT:

Explanation

DISCUSSION: Reporting requirements for adult spousal or intimate partner abuse is not standardized among states and it is the responsibility of the orthopaedic surgeon to understand the laws of his or her
state. The AAOS Advisory statement gives information to assist in meeting the ethical and legal obligations on Domestic and Family Violence and Abuse.
Domestic and family violence affects over 10% of the US population (approximately 32 million Americans). Child abuse and neglect contributed to 1,400 fatalities in 2002 and there was 565,747 reports of suspected elder abuse.
Reporting of suspected child abuse is required in all states. The orthopaedic surgeon should hospitalize elderly victims who are in immediate danger and help develop a plan to insure their safety.

Question 29

A 50-year-old competitive tennis player sustained a shoulder dislocation after falling on his outstretched arm 3 weeks ago. He now reports that he has regained motion but continues to have painful elevation and weakness in external rotation. A subacromial cortisone injection provided 3 weeks of relief, but the pain has returned. Which of the following studies will best aid in diagnosis?

Explanation

DISCUSSION: Based on these findings, the most likely diagnosis is a rotator cuff injury and probable tear; therefore, MRI is the study of choice. CT is preferred for articular fractures. A bone scan is nonspecific and can identify inflammation or occult fracture. Joint aspiration is not likely to identify an effusion. Physical therapy and a functional capacity examination are used to identify weakness during recovery prior to a return to work or sports.
REFERENCES: Hawkins RJ, Bell RH, Hawkins RH, Koppert GJ: Anterior dislocation of the shoulder in the older patient. Clin Orthop 1986;206:192-195.
Matsen FA III, Thomas SC, Rockwood CA: Anterior glenohumeral instability, in Rockwood CA, Matsen FA III (eds): The Shoulder. Philadelphia, PA, WB Saunders, 1990, pp 526-622.

Question 30

The fracture shown in Figure 32 is strongly indicative of what diagnosis?

Explanation

DISCUSSION: Fractures that occur through the primary spongiosa at the subphyseal region of the metaphysis are highly specific for child abuse. On radiographic studies, the metaphyseal lucency in these injuries may appear as either the so-called “bucket-handle” or “metaphyseal corner” fracture. These fractures are not typical features of osteogenesis imperfecta or vitamin D-resistant rickets. The ingestion of lead may lead to thick, transverse bands of increased density at the distal metaphysis. Fractures in the subphyseal region of the metaphysis are not typically seen in children who have osteomyelitis.
REFERENCES: Kocher MS, Kasser JR: Orthopaedic aspects of child abuse. J Am Acad Orthop Surg 2000;8:10-20.
Kleinman PK, Marks SC, Blackbourne B: The metaphyseal lesion in abused infants: A radiologic-histopathologic study. Am J Roentgenol 1986;146:895-905.

Question 31

A 6-year-old boy has leg pain. A radiograph, MRI, CT, and bone scans, and a biopsy specimen are shown in Figures 14a through 14e. What is the most likely diagnosis?

Explanation

DISCUSSION: From an imaging point of view, all of the diagnoses are possible. Biopsy results and cultures are necessary to make the diagnosis. The biopsy specimen shows inflammatory cells and necrotic bone, consistent with osteomyelitis.
REFERENCES: Fletcher BD, Hanna SL: Pediatric musculoskeletal lesions simulating neoplasms. Magn Reson Imaging Clin N Am 1996;4:721-747.
Hanna SL, Fletcher BD, Kaste SC, Fairclough DL, Parham DM: Increased confidence of diagnosis of Ewing sarcoma using T2-weighted MR images. Magn Reson Imaging 1994;12:559-568.

Question 32

A patient who has had neck pain radiating down the arm for the past 4 weeks reports that the pain was excruciating during the first week. Management consisting of anti-inflammatory drugs and physical therapy has decreased the neck and arm symptoms from 10/10 to 3/10. He remains neurologically intact. MRI and CT scans are shown in Figures 5a and 5b. The best course of action should be

Explanation

DISCUSSION: Although the patient has a large herniated nucleus pulposus, the pain has decreased from 10/10 to 3/10 over a 4-week period and the patient is now free of any neurologic symptoms. It is quite likely that further nonsurgical management will continue to resolve his symptoms. In the absence of any neurologic deficits, there is no evidence that the patient is at significant risk for paralysis.
REFERENCES: Saal JS, Saal JA, Yurth EF: Nonoperative management of herniated cervical intervertebral disc with radiculopathy. Spine 1996;21:1877-1883.
Komori H, Shinomiya K, Nakai O, Yamaura I, Takeda S, Furuya K: The natural history of herniated nucleus pulposus with radiculopathy. Spine 1996;21:225-229.

Question 33

Figure 56 is the MR image of a 20-year-old Division I baseball pitcher who has a 1-month history of medial elbow pain in his throwing arm. He also notes a decrease in both control and pitching velocity. An examination reveals tenderness at the medial epicondyle that is exacerbated with valgus elbow stress. The strongest indication for ulnar collateral ligament (UCL) reconstruction is

Explanation

DISCUSSION
All responses represent findings that may be associated with chronic UCL insufficiency. Responses 1 and 3 reflect injury to the UCL itself. In most patients, particularly young patients, UCL reconstruction should not be considered until an appropriate trial of nonsurgical measures has failed. This trial should include, at a minimum, 6 weeks of throwing abstinence followed by rehabilitation to address pitching mechanics and shoulder motion deficits and core strengthening. Although the decision to enter the MLB draft may influence surgical decision making, a pitcher with a 1-month history of elbow symptoms should attempt nonsurgical therapy before making a surgical decision that is not based on clinical data.

Question 34

A full-term newborn has webbing at the knees, rigid clubfeet, a Buddha-like posture of the lower extremities, and no voluntary or involuntary muscle action at and below the knees. Radiographs of the spine and pelvis reveal an absence of the lumbar spine and sacrum. What maternal condition is associated with this diagnosis?

Explanation

DISCUSSION: The history, physical examination, and radiographic findings are consistent with type IV sacral agenesis or caudal regression syndrome. These children are born with no lumbar spine or sacrum. The T12 vertebra is often prominent posteriorly. Popliteal webbing and knee flexion contractures are common with this diagnosis. There is a higher incidence of this diagnosis when the mother has diabetes mellitus. Maternal drug abuse and alcoholism can produce phenotypically unique children but without the findings described here. Maternal idiopathic scoliosis is not associated with caudal regression syndrome.
REFERENCES: Chan BW, Chan KS, Koide T, et al: Maternal diabetes increases the risk of caudal regression caused by retinoic acid. Diabetes 2002;51:2811-2816.
Zaw W, Stone DG: Caudal regression syndrome in twin pregnancy with type II diabetes.

J Perinatol 2002;22:171-174.

Question 35

Based on the MRI scan shown in Figure 6, the abnormal signal is seen in what carpal bone?

Explanation

DISCUSSION: The MRI scan reveals an abnormal signal in the trapezoid, which lies adjacent to the capitate in the distal carpal row. The tumor is a giant cell tumor of bone.
REFERENCES: Cooney WP, Linscheid RL, Dobyns JH: The Wrist: Diagnosis and Operative Treatment. St Louis, MO, Mosby-Year Book, 1998, vol 1, pp 278-282.
Green DP, Hotchkiss RN, Pederson WC (eds): Operative Hand Surgery, ed 4. New York, NY, Churchill Livingstone, 1999, pp 2238-2240.

Question 36

A 36-year-old nurse has had redness, pain, and small vesicles on the pulp of her middle finger for the past 3 days. Management should consist of

Explanation

DISCUSSION: Small vesicles on the fingers of a health care worker suggest a herpetic infection, and the management of choice is observation. Incision and drainage may result in a bacterial infection. Marsupialization is used in the treatment of a chronic paronychia. Calcium gluconate is used for hydrofluoric acid burns, and copper sulfate is used for white phosphorus burns.
REFERENCES: Fowler JR: Viral Infections. Hand Clin 1989;5:613-627.
Jebsen PL: Infections of the fingertip: Paronychias and felons. Hand Clin 1998;14:547-555.

Question 37

During the early swing phase of the normal gait cycle, what lower extremity muscle is primarily contracting?

Explanation

DISCUSSION: Electromyography during walking reveals the tibialis anterior muscle is active during early swing, allowing the foot to clear the ground. All of the other muscles are quiet, as the limb moves forward through space with minimal muscular effort. The other muscles are primarily active during weight acceptance or push-off.
REFERENCES: Gage JR: An overview of normal walking. Instr Course Lect 1990;39:291-303.
Wootten ME, Kadaba MP, Cochran GV: Dynamic electromyography II: Normal patterns during gait. J Orthop Res 1990;8:259-265.

Question 38

What is the most common donor site complication following a free vascularized fibular graft for osteonecrosis of the femoral head?

Explanation

DISCUSSION: Urbaniak and Harvey reported donor site morbidity following free vascularized fibular graft in 198 consecutive patients. At a 5-year follow-up, they reported overall complications in 24% of the patients. The most common complication was a sensory deficit (11.8%), followed by motor weakness (2.7%), flexor hallucis longus contracture (2%), and deep venous thrombosis (less than 1%).
REFERENCE: Urbaniak J, Harvey E: Revascularization of the femoral head in osteonecrosis. J Am Acad Orthop Surg 1998;6:44-54.

Question 39

A 45-year-old man who is a smoker has a significant hemothorax and bilateral closed femoral fractures. On insertion of a chest tube, 1,100 mL of blood was returned. He has had 75 mL of chest tube output over the last 2 hours while being resuscitated in the ICU. His base deficit is now 2 and his urine output has been 3 mL/kg over the last hour. What is the next most appropriate step in management?

Explanation

DISCUSSION: Although this patient had a hemothorax, the bleeding has stopped and he has been resuscitated to a euvolemic status with a small base deficit and good urine output. External fixation of both femurs is an option but an unnecessary step in the treatment algorithm.
REFERENCES: Nork SE, Agel J, Russell GV, et al: Mortality after reamed intramedullary nailing of bilateral femur fractures. Clin Orthop Relat Res 2003;415:272-278.
Pape HC, Zelle BA, Hildebrand F, et al: Reamed femoral nailing in sheep: Does irrigation and aspiration of intramedullary contents alter the systemic response? J Bone Joint Surg Am 2005;87:2515-2522.

Question 40

A 35-year-old man has profound deltoid weakness after sustaining a traumatic anterior shoulder dislocation 6 weeks ago. Electromyographic (EMG) studies confirm an axillary nerve injury. Follow-up examination at 3 months reveals no recovery of function. What is the best course of action?

Explanation

DISCUSSION: Documenting the status of recovery at this time is appropriate; therefore, repeat EMG studies should be conducted to check for early signs of reinnervation. Timing of nerve exploration in this setting is debated, with authors suggesting exploration if there is no sign of recovery at 6 to 9 months.
REFERENCES: Perlmutter GS: Axillary nerve injury. Clin Orthop 1999;368:28-36.
Artico M, Salvati M, D’Andrea V, et al: Isolated lesions of the axillary nerves: Surgical treatment and outcome in twelve cases. Neurosurgery 1991;29:697-700.
Vissar CP, Coene LN, Brand R, et al: The incidence of nerve injury in anterior dislocation of the shoulder and its influence on functional recovery: A prospective clinical and EMG study. J Bone Joint Surg Br 1999;81:679-685.
Pasila M, Jarma H, Kiviluoto O, et al: Early complications of primary shoulder dislocations. Acta Orthop Scand 1978;49:260-263.

Question 41

A 13-year-old baseball pitcher presents with worsening medial-sided elbow pain. He pitches 7 months out of the year, throws 85 pitches per game and plays in two games per week. His fastball speed is approximately 75mph. He regularly plays outfield once he has been relieved of pitching. Which of the following is most likely contributing to his elbow pain? Review Topic

Explanation

Young athletes who throw greater than 80 pitches per game have an increased risk of shoulder and elbow injury. For a 13-year-old, the recommended maximum number of pitches per game is 75.
Little League elbow is a medial-sided overuse injury that occurs in the skeletally immature athlete. During execution of the baseball pitch, tremendous valgus and extension stresses occur at the elbow. Repetitive microtrauma can ultimately injure the medial epicondyle apophysis, ulnar collateral ligament or the flexor-pronator muscle mass. Limiting the number of pitches and innings played per game, as well as the number of months of competitive pitching per year, has been recommended to prevent these overuse injuries in the young athlete.
Olsen et al performed a case control study to determine risk factors associated with the development of shoulder and elbow injuries in adolescent baseball pitchers. Greater than 8 months of competitive pitching per year, more than 80 pitches per game and a fastball speed of greater than 85mph were all associated with increased risk of injury. Continued pitching despite arm fatigue and pain, being a starting pitcher, greater number of warm-up pitches, participating in showcases and regular use of NSAIDs were also associated with injury. The type of pitch (fastball, changeups and breaking balls) and continued play in a different position once being relieved was not associated with increased risk of injury.
Andrews et al authored a review article on ulnar collateral ligament injuries in throwing athletes. According to the USA Baseball Medical/Safety Advisory Committee, young baseball pitchers should avoid breaking pitches, such as curveballs and sliders, and avoid year-round baseball. A minimum of 3 months of complete rest from pitching per year is vital. Youth pitching coaches should be educated to ensure proper pitching mechanics are being reinforced.
Illustration A is a table depicting the recommended maximum number of pitches by age group.
Incorrect Answers:

Question 42

Figures 9a and 9b show the radiographs of a 75-year-old man who underwent a revision total knee arthroplasty with a long-stemmed tibial component. In rehabilitation, he reports fullness and tenderness in the proximal medial leg (at the knee). The strategy that would best limit this postoperative problem is use of

Explanation

DISCUSSION: The problem with this reconstruction is the medial protrusion of the base plate. The use of a base plate with an offset stem can prevent the protrusion and thus the impingement and pain. Allograft bone or smoothing the outline with cement would be just as prominent and likely to cause pain. An ingrowth surface may improve soft-tissue attachment but would still leave the implant protruding medially and likely to cause pain. A nonstemmed tibial base plate would lead to less medial protrusion but at the expense of a smaller area for load carriage on the proximal tibia.
REFERENCE: Gustke K: Cemented tibial stems are not requisite in revision. Orthopedics 2004;27:991-992.

Question 43

An otherwise healthy 16-year-old dancer reports a 1-month history of leg pain. AP and lateral radiographs of the distal femur are shown in Figures 67a and 67b. What is the next most appropriate step in management?

Explanation

DISCUSSION: The radiographs show a very ill-defined, aggressive, moth-eaten bony destruction involving the distal left femoral diaphysis just above the metaphyseal junction. The differential diagnosis includes Ewing’s sarcoma, osteosarcoma, lymphoma of bone, eosinophilic granuloma, osteomyelitis, and others. MRI would further define the lesion, and soft-tissue and intramedullary extension. There is aggressive periosteal reaction in the posteromedial aspect of the adjacent lesion with some multilayered components in the distal interface of the periosteum. The lateral radiograph shows cortical penetration and irregular periosteal reaction of the posterior margin, suggesting some posterior soft-tissue extension at this site as well.
REFERENCES: Gebhardt MC, Ready JE, Mankin HJ: Tumors about the knee in children. Clin Orthop Relat Res 1990;255:86-110.
Menendez LR (ed): Orthopaedic Knowledge Update: Musculoskeletal Tumors. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 175-186.

Question 44

A 30-year-old man sustains a head injury as well as a femur and pelvis fractures as the result of a rollover motor vehicle accident. He is initially comatosed, but recovers cognitive function after 10 days in the hospital. Soon after awakening he complains of wrist pain and an x-ray demonstrates a distal radius fracture. What is the most likely explanation for this delayed diagnosis?

Explanation

DISCUSSION: According to the cited article by Born et al, who prospectively studied the incidence of delayed recognition of skeletal injury at a Level I trauma center over an 18-month period, the majority of missed skeletal injuries result from failure to image the affected extremity. These authors identified 39 fractures in 26 of 1,006 consecutive blunt trauma patients that were not diagnosed in a timely fashion (delays ranging from 1-91 days). Although other factors contributed to the diagnostic failure (23% were visible on admission films and not recognized; 10% were not visible due to inadequate x-rays of appropriate limb; 13% had adequate x-rays but diagnosis could not be made from initial studies), 55% of the fractures that were delayed in diagnosis resulted from failure to image the affected extremity. They went on to conclude that, “although the delay of fracture identification was not felt to contribute to additional long-term cosmetic, functional, or neurologic problems,” continued radiographic surveillance is necessary to prevent diagnostic failure.

Question 45

A 60-year-old woman with a history of osteoporosis fell from a standing height and sustained a supracondylar distal humerus fracture with an intercondylar extension. Which of the following plate constructs yields the highest stiffness for fixation of the fracture?

Explanation

Optimal treatment of distal humeral fractures relies on reestablishment of a congruent articular surface with a fixation construct that is stable enough to allow for early range of motion. Several biomechanical studies have been performed to evaluate the biomechanical strength of various plating configurations. These studies have shown that dual plate configurations are more stable than single plates, regardless of the type of plate used. One third tubular plates have been shown to be significantly weaker than LC-DCP or reconstruction plates, resulting in weaker constructs, and clinically higher rates of hardware failure and nonunion. Whereas traditional teaching has suggested plating in perpendicular planes, recent biomechanical studies have demonstrated that parallel medial and lateral plates confer a greater rigidity to the construct than perpendicular plating schemes.

Question 46

A 5-year-old boy has a deformity of his right arm after falling from a jungle gym. A radiograph is shown in Figure 37. Management should consist of

Explanation

DISCUSSION: Monteggia fractures in children must be recognized. Early appropriate treatment is much easier than delayed reconstruction for a missed radial head dislocation. In younger children, attempts should be made to reduce the ulna fracture and radial head dislocation with traction and manual manipulation. Anterior Monteggia fractures are the most common, and in this variety the radius is much better stabilized in elbow flexion. Posterior Monteggia fractures are less common and may be managed in elbow extension. Closed reduction is much more successful in younger children; ulnar fixation with a rod or plate may be needed in older patients with unstable fractures. Annular ligament repair is rarely needed in the acute fracture.
REFERENCES: Wilkins KE: Changes in the management of Monteggia fractures. J Pediatr Orthop 2002;22:548-554.
Kay RM, Skaggs DL: The pediatric Monteggia fracture. Am J Orthop 1998;27:606-609.
Ring D, Jupiter JB, Waters PM: Monteggia fractures in children and adults. J Am Acad Orthop Surg 1998;6:215-224.

Question 47

Figure 70 is the radiograph of a 14-year-old girl with increasing posterior ankle pain, especially during pointe technique exercises. Nonsurgical measures such as modification, stretching, and injection have been unsuccessful. Which nerve is most vulnerable to injury during endoscopic excision of this lesion?

Explanation

DISCUSSION
The pathology is that of posterior ankle impingement, which is secondary to a symptomatic os trigonum. Endoscopic excision necessitates posteromedial and posterolateral ankle portals. Although plantar numbness has been described as a relatively common postsurgical complication, the neurovascular structure most commonly injured is the sural nerve.

Question 48

Figures 36a and 36b are the radiographs of a 79-year-old woman who has been experiencing increasing tibial pain 10 years after undergoing revision total knee arthroplasty. There is no evidence of infection. What is the most appropriate treatment?

Explanation

DISCUSSION
Stems are available for cemented and press-fit implantation. To be effective, press-fit stems should engage the diaphysis (Figures 36c and 36d). They also assist in obtaining correct limb alignment. Short metaphyseal-engaging stems are associated with failure rates between
16% and 29%. Cemented stems may be shorter than press-fit stems because they do not have to engage the diaphysis. Short, fully cemented stems offer the advantage of metaphyseal fixation. Hybrid stem fixation makes use of the metaphysis for cement fixation with metaphyseal cones or sleeves and diaphyseal-engaging press-fit stems.
RESPONSES FOR QUESTIONS 37 THROUGH 40
Lateral femoral cutaneous nerve
Lateral femoral circumflex artery
Superior gluteal nerve
Superior gluteal artery
Sciatic nerve
Femoral artery
Femoral vein
Femoral nerve
Saphenous branch of the femoral nerve
Profunda femoris artery
Inferior gluteal nerve
Match each description below with the anatomic structure listed above.

Question 49

Which of the following neurovascular structures is at greatest risk during the introduction of acetabular component fixation screws during total hip replacement?

Explanation

Wasielewski et al found on reviewing the literature that vascular injuries during acetabuIar screw placement are an uncommon yet devastating complication of total hip arthroplasty. Damage to the external iliac artery was the most frequent injury yet injury to the external iliac vein and the superior gluteal artery has also been reported Based upon their anatomic study and development of a quadrant
system they found that the posterior superior and posterior inferior quadrants of the acetabulum are the safest locations for screw placement because of better bone stock as well as less neurovascular structures as compared to the anterior quadrants.

Question 50

The teardrop shape marked with an asterisk in Figure 61 represents what anatomic structure?

Explanation

DISCUSSION: The teardrop can be visualized on the obturator outlet view of the pelvis and represents a thick column of bone that runs from the AIIS to the PSIS. Half pins for eternal fixation frames or screws can be inserted into this column for fixation of fractures.
REFERENCES: Gardner MJ, Nork SE: Stabilization of unstable pelvic fractures with supra-acetabular compression external fixation. J Orthop Trauma 2007;21:269-273.
Haidukewych GJ, Kumar S, Prpa B: Placement of half-pins for supra-acetabular external fixation: An anatomic study. Clin Orthop Relat Res 2003;411:269-273.
Kim WY, Hearn TC, Seleem O, et al: Effect of pin location on stability of pelvic external fixation. Clin Orthop Relat Res 1999;361:237-244.

Question 51

Central cord syndrome would most likely be seen in which of the following patients? Review Topic

Explanation

Central cord syndrome is an incomplete spinal cord injury most commonly seen in older patients following hyperextension cervical injury.
Central cord syndrome is most commonly caused by cervical hyperextension in older patients with underlying cervical spondylosis. It is thought to be due to compression between anterior osteophytes and posterior infolded ligamentum flavum during hyperextension. This preferentially affects the motor tracks closest to midline, and thus motor function is impaired greater than sensation, and upper extremities more affected than lower extremities (remember upper motor tracks are more central in the lateral corticospinal tract)
Nowak et al. present a review article on central cord syndrome. They cite the most common cause of central cord syndrome as a hyperextension mechanism in an elderly patient with preexisting spondylosis.
Gupta et al. present a review article on the management of spinal cord injuries. They discuss advances and ongoing study in acute management, surgical techniques, pharmacoptherapies, and cellular transplantation. They recommend a multidisciplinary approach to treating spinal cord injuries.
Dvorak et al. present results of long term follow-up after traumatic central cord syndrome. They found average improvement of ASIA motor scores (AMS) from 58.7 to 92.3. Bowel and bladder control returned in 81% and independent ambulation returned in 86%. Variables correlated with final AMS were AMS at injury, formal education, and presence of spasticity during follow-up.
Illustration A shows the blood supply to the spinal cord. Illustration B shows the area affected by central cord syndrome to help explain why it produces the described deficits.
Incorrect answers:
may be seen in the presence of congenital cervical stenosis. However, this is not the most common cause. Answer 4: Aortic aneurysm repair would more commonly lead to anterior cord syndrome.

Question 52

A 17-year-old girl who initially presented as a child with multiple skeletal lesions, café-au-lait spots, and precocious puberty now has bone pain. A recent bone scan reveals multiple areas of increased scintigraphic uptake, including bilateral proximal femurs. A radiograph is shown in Figure 19. Besides activity modification, what is the next best line of treatment for decreasing her pain?

Explanation

DISCUSSION: McCune-Albright syndrome is the combination of polyostotic fibrous dysplasia, café-au-lait lesions, and endocrine dysfunction. The most common endocrine presentation is precocious development of secondary sexual characteristics. Compared with bone lesions in patients without polyostotic disease, the skeletal lesions in patients with the syndrome tend to be larger, more persistent, and associated with more complications. Bisphosphonate therapy has been shown in several studies to decrease the pain associated with the skeletal lesions of fibrous dysplasia.
REFERENCES: DiCaprio MR, Enneking WF: Fibrous dysplasia: Pathophysiology, evaluation and treatment. J Bone Joint Surg Am 2005;87:1848-1864.
Zacharin M, O’Sullivan M: Intravenous pamidronate treatment of polyostotic fibrous dysplasia associated with McCune Albright syndrome. J Pediatr 2000;137:403-409.

Question 53

What is the most frequent location of entrapment of the deep peroneal nerve?

Explanation

DISCUSSION: The most frequently described entrapment of the deep peroneal nerve is the anterior tarsal tunnel syndrome. This syndrome refers to entrapment of the deep peroneal nerve under the inferior extensor retinaculum. Entrapment can also occur as the nerve passes under the tendon of the extensor hallucis brevis. Compression by underlying dorsal osteophytes of the talonavicular joint and an os intermetatarseum (between the bases of the first and second metatarsals) have previously been described in runners.
REFERENCES: Kopell HP, Thompson WA: Peripheral entrapment neuropathies of the lower extremity. N Engl J Med 1960;262:56-60.
Schon LC, Mann RA: Diseases of the nerves, in Coughlin MJ, Mann RA, Saltzman CL (eds): Surgery of the Foot and Ankle, ed 8. Philadelphia, PA, Mosby-Elsevier, 2007, vol 1, pp 675-677.

Question 54

Examination of a 13-year-old boy with asymptomatic poor posture reveals increased thoracic kyphosis that is fairly rigid and accentuates during forward bending. The neurologic examination is normal. Spinal radiographs show 10 degrees of scoliosis at Risser stage 2, and there is no evidence of spondylolisthesis. A standing lateral view of the thoracic spine is shown in Figure 41. The kyphosis corrects to 50 degrees. Management should consist of Review Topic

Explanation

The radiograph shows excessive thoracic kyphosis (normal 20 degrees to 50 degrees) with multiple contiguous vertebral wedging and end plate irregularity, all consistent with the diagnosis of Scheuermann’s kyphosis. The patient is skeletally immature; therefore, there is the potential for progression of the kyphotic deformity. Extension bracing has shown efficacy in the treatment of Scheuermann’s kyphosis that measures 50 degrees to 74 degrees, and has actually reduced the curvature permanently in some patients. A thoracolumbosacral orthosis may be used if the apex of kyphosis is at T7 or lower. Indications for surgical treatment are controversial, but spinal fusion most likely should not be considered for a painless kyphosis measuring less than 75 degrees.

Question 55

Which of the following nerves is most commonly injured during arthroscopy of the ankle?

Explanation

Neurological complications of account for approximately 49.1% of all complications in Ankle Arthroscopy. Nerve injuries resulted from direct trauma of portal placement. Nerves affected in order: 1) Superficial peroneal 2) Sural 3) Saphenous 4) Deep peroneal.

Question 56

Figures 10a and 10b show the radiographs of an athletic 9-year-old boy who has activity-related anterior knee pain with intact active knee extension. Examination reveals tenderness to palpation over the inferior pole of the patella. There is no effusion or ligamentous instability. Initial management should consist of

Explanation

DISCUSSION: The radiographs show fragmentation of the inferior pole of the patella. This finding, along with the clinical presentation, is most consistent with Sindig-Larsen-Johansson disease. This is an overuse syndrome commonly seen in boys ages 9 to 11 years. The differential diagnosis includes bipartite patella and patellar sleeve fracture. Like most overuse syndromes, Sindig-Larsen-Johansson disease responds to activity modification and nonsteroidal anti-inflammatory drugs. While symptoms usually resolve with short periods of activity restriction, radiographic findings may persist.
REFERENCES: Stanitski CL: Anterior knee pain syndromes in the adolescent. J Bone Joint Surg Am 1993;75:1407-1416.
Stanitski CL: Anterior knee pain syndromes in the adolescent, in Schafer M (ed): Instructional Course Lectures 43. Rosemont, Ill, American Academy of Orthopaedic Surgeons, 1994, pp 211-220.

Question 57

Storage of musculoskeletal allografts by cryopreservation is achieved by

Explanation

DISCUSSION: Cryopreservation uses chemicals to remove cellular water and controlled rate freezing to prevent ice crystal formation. The tissue is procured, cooled to wet ice temperature for quarantine, and then stored in a container with cryoprotectant solution of dimethyl
sulfoxide or glycerol which displaces the cellular water. The controlled rate freezing is then done to prevent ice crystal formation. Fresh allografts are not frozen in order to maintain maximum cellular viability, and this process limits the shelf life of osteochondral allografts. Freeze-drying involves replacement of water in the tissue with alcohol to a moisture level of
5% and then uses a vacuum process to remove the alcohol from the tissue. Preparation of fresh frozen grafts involves freezing the graft twice and packaging the tissue without solution at
minus 80 degrees C.
REFERENCES: American Association of Tissue Banks: Standards for Tissue Banking. MacLean, VA, American Association of Tissue Banks, 1999.
Vangsness CT Jr, Triffon MJ, Joyce MJ, et al: Soft tissue allograft reconstruction of the human knee: A survey of the American Association of Tissue Banks. Am J Sports Med 1996;24:230-234.
Brautigan BE, Johnson DL, Caborn DM, et al: Allograft tissues, in DeLee JC, Drez D Jr (eds): Orthopaedic Sports Medicine: Principles and Practice. Philadelphia, PA, WB Saunders, 2003, pp 205-213.

Question 58

A 23-year-old male college quarterback presents with acute left shoulder pain after being tackled. A radiograph of the injury is shown in figure A. After successful closed reduction, what shoulder position should be avoided in order to minimize the risk of a repeat injury? Review Topic

Explanation

The patient presents with a traumatic posterior shoulder dislocation and radiographic evidence of a reverse Hill-Sachs type injury. The patient should avoid adduction, 90 degrees flexion, and internal rotation in order to decrease the risk of re-dislocation.
Shoulder stability is achieved through the both dynamic and static stabilizers. The static stabilizers include the bony morphology of the joint, glenoid labrum, capsule, and glenohumeral ligaments. The contributions of the glenohumeral ligaments to shoulder stability are dependent upon the position of the humerus relative to the glenoid. Posterior stability is afforded to the joint by the superior glenohumeral ligament (SGHL) and the posterior band of the inferior glenohumeral ligament (IGHL). The SGHL specifically is taught and provides posterior stability with the shoulder in flexion, adduction, and internal rotation.
Kim et. al. reviewed their experience treating 27 athletes diagnosed with traumatic posterior shoulder instability and treated with arthroscopic posterior labral repair and capsular shift. Most patients were found to have an incompletely stripped posterior capsulolabral complex. After arthroscopic repair and shift, all 26 of the 27 patients treated had improved shoulder function and objective scores, a stable shoulder, and were able to return to sport.
Millett et. al. reviewed posterior shoulder instability. They describe the static restraints of the posterior shoulder as the SGHL, posterior band of IGHL, and the coraohumeral ligament (CHL). The SGHL and CHL are both taught in the position of flexion, adduction, and internal rotation, whereas the posterior band of the IGHL is taught in abduction. They describe posterior instability occuring secondary to overhead sports due to repetitive microtrauma causing gradual capsular failure.
Figure A is an axillary radiograph of the left shoulder demonstrating a posterior dislocation and an engaging reverse Hill-Sachs lesion.
Incorrect Answers:

Question 59

A 17-year-old girl has multidirectional instability of the shoulder. What is the most appropriate initial management? Review Topic

Explanation

Multidirectional instability of the shoulder is defined as symptomatic instability in two or more directions (anterior, posterior) but must include a component of inferior instability. Initial treatment should always include physical therapy and instruction in a home exercise program that emphasizes periscapular and rotator cuff strengthening to improve the dynamic stability of the glenohumeral joint. Immobilization has not been shown to be effective. Open capsular shift and arthroscopic capsular plication remain the surgical options when appropriate nonsurgical management fails (typically a minimum of 6 months of dedicated therapy and home program). Thermal capsulorrhaphy remains controversial but is not recommended by many clinicians because of reported complications including recurrent instability, axillary nerve injury, chondrolysis, and capsular injury.

Question 60

A 70-year-old man is experiencing neck pain, progressive weakness, and numbness in his arms and legs without bowel or bladder dysfunction or dysphagia. Upon examination, he has atrophy of his upper extremities but normal muscle bulk in his legs. Strength is diffusely 4/5 throughout. Cervical spine radiographs show spondylosis. Electromyography (EMG) reveals fibrillations with increased amplitude in the extensor carpi radialis and pronator teres. Nerve conduction studies demonstrate slowing conduction diffusely in the sural, peroneal, and ulnar nerves, and severe slowing in the median nerve. Testing of the tongue and thoracic paraspinal muscles does not show fibrillations or positive short waves. What is the most likely diagnosis? Review Topic

Explanation

Physical examination and presentation is consistent with possible cervical radiculopathy vs motor neuron disease. EMG findings are most consistent with cervical radiculopathy. There is denervation (fasciculations and positive short waves) of the C6 innervated muscles consistent with radiculopathy. However, evaluation of other body regions does not show evidence of denervation (tongue, thoracic paraspinal muscles). Fasciculations in the hand muscles were not widespread. Nerve conduction suggests the presence of a peripheral polyneuropathy with possible superimposed median neuropathy. Amyotrophic lateral sclerosis is a motor neuron disease that affects both upper and lower neurons. Presentation includes rapid progression of weakness, muscle atrophy, fasciculations, spasticity, dysarthria, dysphagia, and respiratory compromise.

Question 61

An 18-year-old football player reports acute pain and swelling after a direct injury to his plantar flexed foot. Examination reveals midfoot swelling and tenderness. Nonstanding radiographs are normal. What is the next most appropriate step in management?

Explanation

DISCUSSION: Differentiating between a midfoot sprain and Lisfranc diastasis is critical in the management of the athlete with an acute injury to the midfoot. Greater than 2 mm of displacement between the first and second metatarsals on a weight-bearing radiograph is an indication for anatomic reduction with internal fixation of the tarsometatarsal joints. If no subluxation is noted, treatment should consist of a non-weight-bearing cast for 6 weeks, followed by a gradual return

to activity.
REFERENCES: Mizel MS, Miller RA, Scioli MW (eds): Orthopaedic Knowledge Update: Foot and Ankle 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1998, pp 39-54.
Chiodo CP, Myerson MS: Developments and advances in the diagnosis and treatment of injuries with the transmetatarsal joint. Orthop Clin North Am 2001;32:11-20.

Question 62

A 13-year-old girl has had a firm mass and pain in her right shoulder for the past several weeks. She denies any history of trauma. A radiograph and MRI scan are shown in Figures 31a and 31b. Biopsy specimens are shown in Figures 31c and 31d. What is the most likely diagnosis?

Explanation

DISCUSSION: The patient has osteosarcoma. The radiograph suggests an aggressive primary tumor of bone, and the histology shows malignant cells surrounded by osteoid, classic for osteosarcoma. Ewing’s sarcoma histologically consists of small round blue cells. Osteochondroma and periosteal chondroma occur in the shoulder but have a different histologic pattern and a less aggressive radiographic appearance. Chondrosarcomas rarely occur in children.
REFERENCES: Simon MA, Springfield DS, et al: Osteogenic Sarcoma: Surgery for Bone and Soft Tissue Tumors. Philadelphia, PA, Lippincott Raven, 1998, p 266.
Wold LA, et al: Osteogenic Sarcoma: Atlas of Orthopaedic Pathology. Philadelphia, PA, WB Saunders, 1990, pp 14-15.

Question 63

-A 42-year-old woman has had right wrist pain for 2 years. She tried splint wear and naproxen and has had 3 steroid injections, each time experiencing less relief.

Explanation

Question 64

An 18-year-old collegiate football player injures his right shoulder during a tackle. He reports pain and numbness in the shoulder and numbness radiating to his fingers. His symptoms improve within 15 minutes and he has no residual symptoms. This condition is best known as

Explanation

DISCUSSION: The condition described in this case is known as a stinger or burner. It is caused by stretching the upper trunk of the brachial plexus in the C5 and C6 nerve roots. The symptoms are temporary and last 15 to 20 minutes. There are no residual deficits, unless the patient has had multiple repetitive injuries. Once motor and sensory examination findings and reflexes have normalized, the athlete can return to play. Acute spinal cord injury may cause temporary complete paralysis in the upper and lower extremities with resolution of symptoms within 24 hours. Central cord syndrome affects the upper more than lower extermities and affects mostly elderly patients. Nerve root avulsions lead to permanent deficits and have a poor prognosis for return of function. Guillain-BarDe syndrome is an autoimmune disease that presents as an ascending paralysis with weakness in the legs that spreads to the upper limbs and the face along with complete loss of deep tendon reflexes.
REFERENCES: Safran MR: Nerve injury about the shoulder in athletes. Part 2: Long thoracic nerve, spinal accessory nerve, burners/stingers, thoracic outlet syndrome. Am J Sports Med 2004;32:1063-1076. Aval SM, Durand P Jr, Shankwiler JA: Neurovascular injuries to the athlete’s shoulder: Part I. J Am Acad Orthop Surg 2007;15:249-256.

Question 65

A 35-year-old man with a history of spine surgery 5 years ago reports the recent development of frequent low back pain radiating to the legs. The patient blames a low-energy fall that occurred 9 months ago for the recent symptoms. Radiographs reveal previous interbody fusions of L4-L5 and L5-S1, with hardware present. The vertebrae appear well-fused and stable. What is the most likely cause of the low back pain? Review Topic

Explanation

It is increasingly recognized in the spine literature that fusion of two or more vertebrae produces increased range of motion in adjacent motion segments, resulting in increased stresses and, with time, degeneration of the adjacent disks. Loss of disk height would be an initial indication of disk degeneration. If the patient's fall had caused a fracture, the symptoms would have been immediate.

Question 66

Figure 53 shows the arteriogram of a 45-year-old man who has severe vasculitis. What do the findings show?

Explanation

DISCUSSION: The arterial supply to the hand is abundant and normally duplicated. The deep palmar arch as shown in this arteriogram typically receives its primary contribution from the radial artery which travels deep to the first dorsal compartment tendons and then returns to the volar aspect of the palm through the first web space. The superficial palmar arch receives its supply from the ulnar artery and is not visualized in this patient.
REFERENCE: Cooney WP, Linscheid RL, Dobyns JH (eds): The Wrist: Diagnosis and Operative Treatment. Philadephia, PA, Mosby-Year Book, 1998, p 110.

Question 67

Which stress fracture location is reported most frequently among ballet dancers?

Explanation

DISCUSSION
Stress fractures are a frequent overuse injury among professional ballet dancers. The most common location is at the proximal metaphyseal-diaphyseal junction of the second metatarsal. Repetitive stress injuries and fractures of the tibial sesamoid, tarsal navicular, and base of the fifth metatarsal occur among other athletes.
RECOMMENDED READINGS
O'Malley MJ, Hamilton WG, Munyak J, DeFranco MJ. Stress fractures at the base of the second metatarsal in ballet dancers. Foot Ankle Int. 1996 Feb;17(2):89-94. PubMed PMID: 8919407. View Abstract at PubMed
Micheli LJ, Sohn RS, Solomon R. Stress fractures of the second metatarsal involving Lisfranc's joint in ballet dancers. A new overuse injury of the foot. J Bone Joint Surg Am. 1985 Dec;67(9):1372-5. PubMed PMID: 4077907. View Abstract at PubMed
Gehrmann RM, Renard RL. Current concepts review: Stress fractures of the foot. Foot Ankle Int. 2006 Sep;27(9):750-7. Review. PubMed PMID: 17038292. View Abstract at PubMed

Question 68

During what phase of the throwing motion is the highest torque measured across the glenohumeral joint?

Explanation

DISCUSSION: Electromyography is used to evaluate muscular firing patterns about the shoulder during the throwing sequence. The rotator cuff muscles and biceps are relatively inactive during the acceleration phase, whereas the pectoralis major, serratus anterior, latissimus dorsi, and subscapularis show highest activity. By contrast, deceleration is accomplished by the rotator cuff musculature and the larger trunk muscles acting in concert to slow down the arm. It is during this phase of follow through that the highest torque is measured secondary to eccentric muscle contraction.
REFERENCES: Jobe FW, Moynes DR, Tibone JE, Perry J: An EMG analysis of the shoulder in pitching: A second report. Am J Sports Med 1984;12:218-220.
Pappas AM, Zawacki RM, Sulliva TJ: Biomechanics of baseball pitching: A preliminary report. Am J Sports Med 1985;13:216-222.
Altcheck DW, Dines DM: Shoulder injuries in the throwing athlete. J Am Acad Orthop Surg 1995;3:159-165.

Question 69

A 37-year-old man who works in a factory has isolated, lateral unicompartmental pain about his knee with activities. Nonsurgical management has failed to provide relief. The radiograph shown in Figure 45 reveals a tibiofemoral angle of approximately 15 degrees which is clinically correctable to neutral. What is the best surgical option in this patient?

Explanation

DISCUSSION: Patients with a valgus alignment about the knee can have lateral compartment arthritis. Similar to a high tibial osteotomy, a supracondylar femoral osteotomy is indicated in younger patients who have a more active lifestyle and isolated unicompartmental disease. In this young patient who works in a factory and has a valgus knee, a medial closing wedge supracondylar femoral osteotomy is the treatment of choice. The role of arthroplasty is limited in younger patients.
REFERENCES: Mathews J, Cobb AG, Richardson S, et al: Distal femoral osteotomy for lateral compartment osteoarthritis of the knee. Orthopedics 1998;21:437-440.
Cameron HU, Botsford DJ, Park YS: Prognostic factors in the outcome of supracondylar femoral osteotomy for lateral compartment osteoarthritis of the knee. Can J Surg 1997;40:114-118.

Question 70

A 20-year-old man with fascioscapulohumeral dystrophy has severe scapular winging of both shoulders. He can no longer abduct above 80 degrees, and it affects his activities of daily living. A clinical photograph is shown in Figure 26. Definitive management should consist of

Explanation

DISCUSSION: The patient’s history is typical of patients with severe fascioscapulohumeral dystrophy. The scapular winging can be so pronounced that there is significant loss of function of the upper extremity. The surgical options include transfer of the pectoralis major muscle with a tendon graft or scapulothoracic fusion. The latter is a technically demanding procedure but can provide a very stable platform for the upper extremity. Most patients will see increased elevation of the extremity once the scapula is stabilized. Pectoralis minor transfer has not been described and would not be effective.
REFERENCES: Shapiro F, Specht L: The diagnosis and orthopaedic treatment of inherited muscular diseases of childhood. J Bone Joint Surg Am 1993;75:439-454.
Bunch WH, Siegel IM: Scapulothoracic arthrodesis in fascioscapulohumeral muscular dystrophy: Review of seventeen procedures with three to twenty-one-year follow-up. J Bone Joint Surg Am 1993;75:372-376.

Question 71

During right knee anterior cruciate ligament (ACL) reconstruction, after drilling an appropriately positioned and referenced tibial tunnel, the surgeon finds that the transtibial guide is placing the femoral tunnel at 11:30 within the intercondylar notch. Which of the following choices will best enable appropriate graft placement in this clinical scenario? Review Topic

Explanation

Anatomic placement of the femoral tunnel is best achieved in this clinical scenario by drilling the femoral tunnel through the anteromedial portal or via a two-incision technique. Several recent studies have demonstrated the difficulty that may be encountered in restoring true ACL anatomy on the femoral side when placing a femoral tunnel through a transtibial technique. While this is not always the case and this technique may be reasonable and sufficient, it is important for orthopaedic surgeons to critically assess tunnel placement intraoperatively and postoperatively to
minimize errant tunnel placement, demonstrated in the literature as the most common cause of ACL failure and need for revision. In this not uncommon clinical scenario, simply converting to a two-incision ACL technique or drilling through the anteromedial portal with the knee hyperflexed will permit accurate femoral tunnel placement and increase the likelihood of an optimal clinical outcome. Femoral tunnel accuracy with these techniques is enhanced by a lower starting point in the intercondylar notch. Familiarity with these techniques is valuable for surgeons performing ACL reconstruction. Revising the tibial tunnel in this scenario would likely lead to bone compromise of the proximal tibia and may interfere with graft fixation and incorporation. Converting to a double-bundle ACL with a transtibial technique would not correct the vertical femoral tunnel. Hyperflexion of the knee may improve femoral tunnel placement to some extent, but is unlikely to allow anatomic placement of a femoral tunnel when the transtibial guide lies in a clearly excessive vertical position.

Question 72

What is the most appropriate treatment at this time?

Explanation

DISCUSSION
Prompt diagnosis and treatment of patients with spinal epidural abscess is crucial to maintain and/or improve neurologic function. This clinical scenario stresses the importance of advanced imaging studies. It is also important to recognize the imaging features of spinal epidural abscess. T1-weighted gadolinium-enhanced images show ring enhancement with a central nonenhancing, low-signal area. In such a case, urgent decompression is indicated. Because of the location of the abscess, which is anterior to the spinal cord, an anterior decompression and reconstruction (ie, fusion) is probably the best treatment plan. Steroids are contraindicated in the presence of an epidural abscess. IV antibiotics alone will not adequately treat a patient with a neurological deficit. A posterior laminectomy and fusion will not safely allow access to the abscess.
RECOMMENDED READINGS
Bluman EM, Palumbo MA, Lucas PR. Spinal epidural abscess in adults. J Am Acad Orthop Surg. 2004 May-Jun;12(3):155-63. Review. PubMed PMID: 15161168. View Abstract at PubMed Ghobrial GM, Beygi S, Viereck MJ, Maulucci CM, Sharan A, Heller J, Jallo J, Prasad S, Harrop JS. Timing in the surgical evacuation of spinal epidural abscesses. Neurosurg Focus. 2014 Aug;37(2):E1. doi: 10.3171/2014.6.FOCUS14120. PubMed PMID: 25081958. View Abstract
at PubMed
This is the last question of the exam.

Question 73

A 39-year-old female presents with the following motor vehicle crash with the injury seen in Figure A (immobilized in a pelvic binder). The iatrogenic neurologic injury most commonly caused by placement of the anterior construct for this injury, as shown in Figure B, would cause which of the following?

Explanation

This patient was treated with posterior stabilization, and an anterior subcutaneous internal fixator (ASIF). The most common neurologic injury seen following placement of the ASIF construct is irritation of the lateral femoral cutaneous nerve (LFCN), causing numbness and/or pain of the lateral thigh.
Unstable pelvic fractures can be treated in a multitude of ways. The ASIF construct is typically created by placing long pelvic screws or polyaxial pedicle screws in the supraacetabular region, similar to the supraacetabular pins for an anterior external fixator. Then a curved bar is placed subcutaneously and connected to the supraacetabular screws. They are typically removed after 3-4 months when fracture healing is complete.
Vaidya et al. present a retrospective review of the use of ASIF as definitive treatment of unstable pelvic fractures. All patients in the study tolerated the construct well. LFCN irritation was seen in 30% of patients, and resolved in all but one patient.
Müller et al. present a retrospective review of the use of posterior stabilization and ASIF. They report an acceptably low complication rate, and good to excellent outcomes in 64.5% of patients.
Figure A is a radiograph demonstrating a right APC3 and left APC2 pelvic injury, imaged in a pelvic binder. Figure B is a postoperative radiograph following posterior stabilization and ASIF.
Incorrect answers:

Question 74

A 55-year-old man reports increasing weakness in his arms that has progressed to his lower limbs, resulting in frequent tripping and falling. Examination reveals weakness in shoulder abduction and external and internal rotation bilaterally. Fasciculation is noted. He also has weakness in elbow flexion and extension bilaterally, and his grip strength is diminished. An electromyogram and nerve conduction velocity studies show decreased amplitude of compound motor action potential, slightly slowed motor conduction velocity, and denervation signs with decreased recruitment in all extremities. The sensory study is normal. Based on these findings, what is the most likely diagnosis?

Explanation

DISCUSSION: The major determinant of ALS (Lou Gehrig disease) is progressive loss of motor neurons. The loss usually begins in one area, is asymmetrical, and later becomes evident in other areas. The first signs of ALS may include either upper or lower motor neuron loss. Recognition of upper motor neuron involvement depends on clinical signs, but electromyography and nerve conduction velocity studies can help identify lower motor neuron involvement. Electrodiagnostic abnormalities in three or more areas are required to make a definitive diagnosis. The motor unit potentials (MUPs) changes in ALS include impaired MUPs recruitment, unstable MUPs, and abnormal MUPs size and configuration. A number of abnormal spontaneous discharges can occur with ALS, especially fibrillation potentials and fasciculation potentials. In ALS, the motor nerve conduction study will be abnormal, but a co-existing normal sensory study is definitive for this disease.
REFERENCES: de Carvalho M, Johnsen B, Fuglsang-Frederiksen A: Medical technology assessment: Electrodiagnosis in motor neuron diseases and amyotrophic lateral sclerosis. Neurophysiol Clin 2001;31:341-348.
Daube JR: Electrodiagnostic studies in amyotrophic lateral sclerosis and other motor neuron disorders. Muscle Nerve 2000;23:1488-1502.
Troger M, Dengler R: The role of electromyography (EMG) in the diagnosis of ALS. Amyotroph Lateral Scler Other Motor Neuron Disord 2000;1:S33-S40.

Question 75

A 20-year-old woman with a history of subtotal meniscectomy has a painful knee. What associated condition is a contraindication to proceeding with a meniscal allograft?

Explanation

DISCUSSION: Patients with significant joint malalignment place increased stresses on the allograft, and this malalignment must be corrected to decrease the likelihood of meniscal allograft failure. None of the other options would lead to failure of the allograft.
REFERENCE: Koval KJ (ed): Orthopaedic Knowledge Update 7. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, p 499.

Question 76

In the evaluation of somatosensory-evoked potential waveforms for intraoperative neuromonitoring for spinal surgery, the minimum criteria for determining potentially significant changes include Review Topic

Explanation

The established criteria for interpreting a significant change are 50% decrease in signal amplitude, 10% latency increase, and/or a complete loss of potential. Intraoperative spinal cord monitoring during spinal surgery generally consists of a combination of monitoring modalities. Somatosensory-evoked potentials in combination with intraoperative electromyography can provide adequate coverage of sensory and motor components of spinal cord and nerve root function. Significant changes in evoked potential waveform characteristics can reflect dysfunction of the ascending somatosensory system.

Question 77

Which of the following is true regarding plating of humeral shaft fractures compared to intramedullary nailing?

Explanation

DISCUSSION: Lin et al found less blood loss with intramedullary nailing than plating, but nailing was also associated with increased shoulder surgery due to disruption of the rotator cuff tendon during insertion. Meekers et al found a higher union rate, better functional results and a lower reoperation rate after plate and screw fixation versus nailing. They concluded that plating was superior in most cases of humeral shaft fracture, except for pathological fractures, very obese patients, and open fractures.

Question 78

Which of the following complications is uniquely associated with an anterior approach to the lumbosacral junction?

Explanation

DISCUSSION: Retrograde ejaculation is a sequela of injury to the superior hypogastric plexus. The structure needs protection, especially during anterior exposure of the lumbosacral junction. The use of monopolar electrocautery should be avoided in this region. The ideal exposure starts with blunt dissection just to the medial aspect of the left common iliac vein, sweeping the prevertebral tissues toward the patient’s right side. Although erectile dysfunction can be seen after spinal surgery, it is not typically related to the surgical exposure because erectile function is regulated by parasympathetic fibers derived from the second, third, and fourth sacral segments that are deep in the pelvis and are not at risk with the anterior approach. The other choices are complications of spinal surgery but are not uniquely associated with an anterior L5-S1 exposure.
REFERENCES: Flynn JC, Price CT: Sexual complications of anterior fusion of the lumbar spine. Spine 1984;9:489-492.
Watkins RG (ed): Surgical Approaches to the Spine, ed 1. New York, NY, Springer-Verlag, 1983, p 107.
An HS, Riley LH III: An Atlas of Surgery of the Spine. New York, NY, Lippincott Raven, 1998, p 263.

Question 79

At the time of revision knee arthroplasty, a surgeon performs a rectus snip to gain exposure to the knee. When compared with a standard parapatellar approach, what is the expected outcome?

Explanation

DISCUSSION:
Rectus snip during total knee arthroplasty has no effect on motion or strength at long-term follow-up. It has not been associated with extensor mechanism lag.

Question 80

An adult patient has an 8- x 4- x 10-cm soft-tissue mass located within the adductor compartment of the thigh. Staging studies should consist of

Explanation

DISCUSSION: The appropriate staging studies should consist of MRI and a radiograph of the primary lesion and CT of the chest. MRI is superior to CT for soft-tissue imaging. CT may be useful for evaluating the cortex of bone for invasion by tumor. Bone scans are not commonly used because soft-tissue sarcomas rarely metastasize to bone. CT of the abdomen and pelvis is not typically ordered except for possible liposarcoma. With liposarcoma, there may be a synchronous or metastatic retroperitoneal liposarcoma.
REFERENCES: Demetri GD, Pollock R, Baker L, et al: NCCN sarcoma practice guidelines: National Comprehensive Cancer Network. Oncology (Huntingt) 1998;12:183-218.
Pollock R, Brennan M, Lawrence W Jr: Society of Surgical Oncology practice guidelines: Soft-tissue sarcoma surgical practice guidelines. Oncology (Huntingt) 1997;11:1327-1332.

Question 81

A 24-year-old man has had pain in the left knee for the past several months. He reports that initially the pain was associated with weight-bearing activities, but it has now become more constant. He denies any swelling but reports a lateral fullness at the tibial plateau. Figures 23a through 23e show radiographs, a bone scan, and T1- and T2-weighted MRI scans. What is the most likely diagnosis?

Explanation

DISCUSSION: The radiographs reveal a lytic subchondral lesion that has a poorly defined margin and lacks mineralization. The bone scan confirms an active lesion that has central photopenia, producing the characteristic doughnut configuration. The MRI scans confirm the presence of a subchondral lesion that is modestly expansile at the lateral plateau and has low signal intensity on the T1-weighted image and a mixed high signal on the T2-weighted image. These features strongly suggest giant cell tumor of bone, more than 50% of which appear around the knee. Simple cyst is excluded by the MRI characteristics. Fibrous dysplasia is unlikely to be in a subchondral location and typically does not show this intensity of uptake on bone scan.
REFERENCES: Parsons TW: Benign bone tumors, in Fitzgerald RH, Kaufer H,

Malkani AL (eds): Orthopaedics. St Louis, MO, Mosby, 2002, pp 1027-1035.
Resnick D, Kyriakos M, Greenway GD: Tumors and tumor-like lesions of bone: Imaging and pathology of specific lesions, in Resnick D (ed): Diagnosis of Bone and Joint Disorders, ed 4. Philadelphia, PA, WB Saunders, 2002, vol 4, pp 3939-3962.

Question 82

A 27-year-old man has recurrent right shoulder instability. He first dislocated his shoulder in college while playing rugby and was treated nonsurgically. Since then, he has sustained nearly 1 dozen dislocations and says that his shoulder always feels “loose.” The shoulder recently dislocated in his sleep and while he was putting on clothes. Which factor is a contraindication to an arthroscopic soft-tissue repair?

Explanation

CLINICAL SITUATION FOR QUESTIONS 90 THROUGH 92
Figure 90 is the radiograph of a 14-year-old pitcher who plays in a year-round baseball program and has vague pain in his dominant shoulder. The pain occurs with throwing, and it has been worsening for 2 months. Pain typically occurs during the late cocking phase of throwing. He has no tenderness of the rotator cuff and 5/5 rotator cuff strength. His arc of motion is symmetric between his dominant and nondominant arms. The sulcus sign is negative.

Question 83

Reverse total shoulder arthroplasty improves kinematics in the rotator cuff deficient joint by what directional change to the center of rotation? Review Topic

Explanation

Surgical indications for reverse total shoulder arthroplasty are expanding. In the setting of rotator cuff tear arthroplasty in which the native humeral head migrates superiorly, these implants impart several kinematic advantages. Implant center of rotation medial to the former joint surface improves glenoid component stability as the resultant force vector passes through the component throughout the arc of motion. A stable and fixed fulcrum for elevation is provided by matched radius of curvature between the glenoid and humeral components. A more distal center of rotation increases resting length and tone of the deltoid muscle, improving its effectiveness as a shoulder elevator. Medialized joint center of rotation increases the moment arm of the deltoid, requiring less muscle force to produce a given torque. This results in decreased articular shear stress.

Question 84

Avascular necrosis

Explanation

Slide
A 9-year-old girl sustains an injury (Slide) as a result of a fall. What is her risk of avascular necrosis:

Question 85

A 39-year-old male falls off his bicycle and complains of neck pain and tingling in his fingers. Trauma series radiographs are seen in Figures A and B. Which of the following is likely to be true? Review Topic

Explanation

This patient has ankylosing spondylitis (AS). HLA-B27 is positive in 90% of patients with this disease. This tends to occur in younger patients (as opposed to DISH, which happens in older male patients).
Cervical spine fractures are not uncommon in ankylosing spondylitis because of osteoporosis and the long lever arm from fused vertebrae. They commonly occur because of hyperextension of the cervical spine (usually C5-7) and have a high rate of neurologic injury. AS fractures have a higher rate of neurologic injury than DISH fractures. Posterior decompression and stabilization with long constructs is necessary
Whang et al. reviewed spine injuries in 12 patients with AS and 18 patients with DISH. Most injuries involved C5-C7. Patients with AS were more likely to have severe neurologic injury (41% ASIA A) than DISH (44% ASIA E). There was 81% good-excellent outcome and 4 deaths related to halo vest use.
Caron et al. reviewed spine fractures in patients with ankylosing spine disorders (AS and DISH). AS patients were younger than DISH patients. Spinal cord injury was present in 58%. Surgery was performed on 67% and comprised instrumentation 3 levels above/below the injury. Mortality correlated with age. Mortality was 32%.
Westerveld et al. performed a systematic review on spine injuries in ankylosing spinal disorders. Most patients had sustained low energy trauma (fall from sitting/standing). In DISH, most fractures were through the vertebral body. In AS, vertebral body fractures equaled those through the disc. Surgery was performed for neurological deterioration, unstable fracture and the presence of an epidural hematoma.
Figure A shows a hyperextension injury at C6-7 (Type I, disc or Type IV,anterior disc, posterior body) cervical spine fracture in ankylosis spondylitis. Visible radiographic characteristics include osteopenia, bamboo spine, marginal syndesmophytes and ossfication of the disc space. Figure B is a chest radiograph showing thoracic syndesmophytes consistent with ankylosing spondylitis. Figure C shows bilateral sacroilitis and hip joint space narrowing typical of ankylosing spondylitis. Illustration A shows the Caron classification of spine fractures in ankylosing spondylitis (Type A, disc injury; Type B, body injury; Type C, anterior body, posterior disc injury; Type D, anterior disc, posterior body injury). Illustration B shows the difference between the marginal osteophytes of AS and nonmarginal osteophytes of DISH in the cervical spine. If you have osteophytes that are building up, and project out anterior to the anterior cortex of the vertebral bodies, like "flowing wax" it is DISH.
Incorrect Answers:
1:
This
is
characteristic
of
Klippel-Feil
syndrome

Question 86

An 18-year-old woman sustains a twisting injury of the knee while skiing. Figures 7a and 7b show the radiograph and coronal MRI scan of the knee. In addition to the injury shown, what is the most likely associated injury?

Explanation

DISCUSSION: The MRI scan shows a Segond fracture, which is a small avulsion of the lateral joint capsule from the anterolateral aspect of the proximal tibia. It is almost always associated with anterior cruciate ligament rupture and often with a tear of either the medial or lateral meniscus.
REFERENCES: Goldman AB, Pavlov H, Rubenstein D: The Segond fracture of the proximal tibia: A small avulsion that reflects major ligamentous damage. Am J Roentgenol 1988;151:1163-1167.
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 87

A patient with deficient anteroinferior bone stock undergoes a Latarjet procedure that transfers a portion of the coracoid to the glenoid rim and secures it with two screws. After surgery, the patient reports numbness on the anterolateral forearm. To verify the diagnosis, what muscle should be tested for strength?

Explanation

DISCUSSION: A Latarjet procedure is similar to a Bristow procedure, but with the Latarjet procedure a larger portion of the coracoid is transferred to the scapular neck at the anteroinferior glenoid. As in a Bristow procedure, if the fragment is pulled or twisted during the dissection or during fixation, the musculocutaneous nerve can be injured. With loss of biceps function, elbow flexion and forearm supination will be weaker.
REFERENCES: Ho E, Cofield RH, Balm MR, Hattrup SJ, Rowland CM: Neurologic complications of surgery for anterior shoulder instability. J Shoulder Elbow Surg 1999;8:266-270.
Boardman ND 3rd, Cofield RH: Neurologic complications of shoulder surgery. Clin Orthop 1999;368:44-53.
Allain J, Goutallier D, Glorion C: Long-term results of the Latarjet procedure for the treatment of anterior instability of the shoulder. J Bone Joint Surg Am 1998;80:841-852.

Question 88

Which of the following factors has been shown to increase mortality in poly-trauma patients with severe head injuries?

Explanation

DISCUSSION: The factor most likely to adversely affect long term outcome in poly-trauma patients with severe brain injury is intraoperative hypotension.
Chesnut et al demonstrated that hypotension (SBP <90mmHg) was profoundly detrimental, occurring in 35% of these patients and associated with 150% increase in mortality.
Pietropaoli et al reviewed 53 patients with severe head injuries and required early surgical intervention (surgery within 72 hours of injury). All patients were initially normotensive on arrival. There were 17 patients (32%) who developed intra-operative hypotension and 36 (68%) who remained normotensive throughout surgery. The mortality rate was 82% in the IH group and 25% in the normotensive group.

Question 89

What is the preferred treatment of displaced distal clavicle fractures in children less than eight years old?

Explanation

DISCUSSION: Pediatric distal clavicle fractures are typically treated non-operatively because of the great osteogenic capacity of the intact inferior periosteum. The coracoclavicular ligaments remain attached to the periosteum and new bone fills any remaining bony gaps within the periosteal sleeve. Recent articles by Nenopoulos et al recommend sling immobilization for the majority of fractures (84%) and only attempt surgical fixation for children >8 years old with severely displaced fractures (>2 cortical diameters). They found excellent function with conservative treatment and union in all fractures. Surgical care resulted in improved cosmetic appearance.

Question 90

Which of the following is a true statement regarding thoracic disk herniations? Review Topic

Explanation

Symptomatic herniations of the thoracic spine are much less common than those of the cervical or lumbar region. They tend to occur most commonly during the third to fifth decades of life and although they can be found at all levels, they are most
common in the lower third near the thoracolumbar region. Posterior laminectomy and disk excision has the highest rate of neurologic deterioration and is not recommended. Multiple studies have shown that herniated thoracic disks can be found at one or more levels in 40% of asymptomatic individuals.

Question 91

Figures 21a and 21b show the radiographs of a 12-year-old patient with an L4-level myelomeningocele who has scoliosis that has been slowly progressing for the past several years. There has been no loss of motor function. An MRI scan shows no syringomyelia or increased hydrocephalus. Management should consist of

Explanation

DISCUSSION: Scoliosis is a common occurrence in children with myelomeningocele, with the incidence increasing as the neurologic level moves cephalad. The rate of pseudarthrosis for isolated anterior or posterior fusions has been reported as high as 75%. The combination of anterior and posterior fusions with some type of instrumentation has been shown to decrease the rate of pseudarthrosis to 20%. Brace treatment in smaller curves can be used as a temporizing measure to delay surgery, but as with idiopathic scoliosis, the brace is ineffective for larger curves. Observation is not indicated with a curve of this magnitude.
REFERENCES: Ward WT, Wenger DR, Roach JW: Surgical correction of myelomeningocele scoliosis: A critical appraisal of various spinal instrumentation systems. J Pediatr Orthop 1989;9:262-268.
Muller EB, Nordwall A: Brace treatment of scoliosis in children with myelomeningocele. Spine 1994;19:151-155.

Question 92

A 35-year-old man reports a 2-year history of right groin pain. The pain is made worse with hip flexion, prolonged sitting, and cycling. A radiograph and MRI scan are shown in Figures 16a and 16b. Nonsurgical management has failed to provide relief. What is the best surgical option?

Explanation

DISCUSSION: The patient has cam-type femoral acetabular impingement. He still has a well-maintained joint space without significant degenerative changes, and given his age a joint preserving procedure would be the procedure of choice. A reverse periacetabular osteotomy may be considered in a retroverted acetabulum; however, that is not the case here. A femoral neck osteochondroplasty is required to remove the cam of bone and reshape the femoral head- neck junction to improve the femoral head/neck ratio (femoral head offset). Typically, in isolated cam impingement, cartilage damage in the anterior-superior acetabulum precedes labral damage. Labral debridement alone does not address the pathology of impingement. In cases where labral detachment is present, reattachment has been shown to be superior to labral resection.
REFERENCES: Espinosa N, Rothenfluh DA, Beck M, et al: Treatment of femoro-acetabular impingement: Preliminary results of labral refixation. J Bone Joint Surg Am 2006;88:925-935.
Parvizi J, Leunig M, Ganz R: Femoroacetabular impingement. J Am Acad Orthop Surg 2007;15:561-570. Trousdale RT: Acetabular osteotomy: Indications and results. Clin Orthop Relat Res 2004;429:182-187.

Question 93

-A 37-year-old woman has a 2-month history of weakness in thumb and finger extension, but has normal radial deviation during extension of the wrist. An MRI scan of her forearm shows no abnormality. She does not recall any traumatic event. Needle electromyography findings show fibrillations and reduced

Explanation

Question 94

A 13-year-old pitcher is hit in the left intercostal space by a line drive ball. He collapses, is apneic and unresponsive, and his radial pulse is absent. What is the next step in management? Review Topic

Explanation

Sudden death in athletes without structural cardiac damage is referred to as commotio cordis. This is an emergency. The immediate priorities are protection of the airway, starting CPR, and early cardioversion as this patient has an arrhythmia. It is hypothesized to occur from apnea, vasovagal reflex, or ventricular arrhythemia as reported by Maron and associates from the direct impact of the baseball during a vulnerable part of the cardiac rhythm. Janda and associates reported that soft-core baseballs may not differ from standard baseballs with regard to the risk of fatal chest-impact injury while playing baseball. High survival rates are associated with rapid treatment.

Question 95

-What is the most appropriate initial treatment?

Explanation

DISCUSSION FOR QUESTIONS 83 AND 84
Based upon the history and description of the wound, this patient has sustained a frostbite injury to the anterior skin without evidence of infection. Frostbite, a thermal injury to local tissues, can be classified into first-, second-, third-, and fourth-degree injuries. First-degree injuries are characterized by a central whitish area surrounded by erythema. Second- and third-degree injuries are characterized by blisters that appear within the first 24 hours. Second-degree blisters are clear or cloudy, while third-degree blisters are hemorrhagic. Fourth-degree injuries are characterized by tissue necrosis. Treatment of a frostbite injury should begin as soon as it is identified, even if severity has not been determined. Treatment includes protection against mechanical irritation and keeping the injured area away from heat. The limb should be elevated and clear blisters debrided; dark blisters should be drained but not debrided. Topical treatment includes aloe application every 6 hours (silver sulfadiazine for open wounds). Nonsteroidal anti-inflammatory drugs can be given along with PCN G (500,000 U) or clindamycin (600 mg) IV every 6hours for 48 to 72 hours as prophylaxis against infection.Multiple skin incisions on the front of the knee place the skin at healing risk after surgery.
Skin oxygenation is further compromised by a lateral release, which disrupts the superior lateral geniculate artery in the peripatellar vascular anastomosis. When addressing compromised perfusion to the skin, the orthopaedic surgeon may consider not performing a lateral release, using the medial parapatellar incision,and/or not using a tourniquet during surgery. In this patient, the use of cold therapy further compromised perfusion to the skin. This patient’s wound does not reflect infection, but rather frostbite from the compromised skin perfusion and the application of cold therapy.

The physiologic responses to the effects of freezing temperatures on limbs have been categorized into 4 phases. Phase I, cooling and freezing, is characterized by vasoconstriction and vasospasm. The freezing results in mechanical destruction of cell membranes in endothelial cells in small capillaries. Phase II,rewarming, initiates as heat absorbed by the limb begins an exothermic reaction as extracellular and intracellular crystals melt. Intracellular swelling occurs and small capillaries become highly permeable,resulting in extravasation of fluid and causing edema and blisters. Phase III is characterized by progressive tissue injury resulting from inflammation, vascular stasis, and thrombosis leading to ischemia.Phase IV is recovery that can progress along 3 potential pathways: complete healing, healing with later sequelae, or early tissue necrosis leading to gangrene.
CLINICAL SITUATION FOR QUESTIONS 85 THROUGH 87
Figure 85 is the radiograph of a 13-year-old right-handed baseball player who has experienced 2 months of right-dominant shoulder pain. As a pitcher, he says he cannot “throw hard” without pain, and he develops a dull ache if he throws more than 15 pitches.

Question 96

The CT scan reveals a nondisplaced greater trochanteric fracture. The patient is now experiencing severe pain. What is the most appropriate treatment at this time?

Explanation

DISCUSSION
This patient presents with significant polyethylene wear, which can lead to both osteolysis and synovitis. However, synovitis usually manifests as a mild to moderate chronic ache, which should explain the discomfort. Although infection should always be ruled out with new-onset pain, no clinical parameters suggest acute hematogenous infection. Similarly, without any mention of back pain or neuropathy, radicular pain from the spine is unlikely. If this patient has a nondisplaced greater trochanteric fracture noted on MR imaging, the optimal immediate mode of treatment is to not rush into surgery despite the mild osteolysis. The patient’s severe pain is likely attributable to the nondisplaced greater trochanteric fracture rather than wear-induced synovitis, which typically presents as a mild to moderate ache. It is recommended to
allow the fracture to heal to avoid fracture displacement. Once the fracture is healed, a revision surgery with liner exchange can be recommended. Based on this clinical scenario, the acetabular component is within what is largely considered the “safe-zone” in THA. Despite this patient’s dislocations, the preferred treatment modality is to revise to a constrained liner. This patient had a well-functioning hip for longer than 15 years. Therefore, conversion to a constrained liner is the best treatment.

Question 97

A 73-year-old man who underwent repair of the left rotator cuff 6 years ago reports good pain relief but notes residual weakness of the left shoulder, especially with overhead tasks. He denies having pain at night and has minimal discomfort with activities of daily living but is dissatisfied with his shoulder strength. Radiographs show an acromiohumeral interval of 2 mm. Appropriate management should consist of

Explanation

DISCUSSION: An exercise program to strengthen the deltoid and remaining rotator cuff will most likely offer the best results. Revision rotator cuff surgery yields better results in decreasing pain than improving strength and function, and this patient has only minimal pain. Tendon transfers, involving the use of the latissimus dorsi or teres major, have been used when the rotator cuff is deemed irreparable but are not indicated in elderly patients with minimal symptoms.
REFERENCES: Bigliani LU, Cordasco FA, McIlveen SJ, Musso ES: Operative treatment of failed repairs of the rotator cuff. J Bone Joint Surg Am 1992;74:1505-1515.
DeOrio JK, Cofield RH: Results of a second attempt at surgical repair of a failed initial rotator-cuff repair. J Bone Joint Surg Am 1984;66:563-567.
Gerber C, Vinh TS, Hertel R, Hess CW: Latissimus dorsi transfer for the treatment of massive tears of the rotator cuff: A preliminary report. Clin Orthop 1988;232:51-61.

Question 98

Histologically, synovial chondromatosis is characterized by

Explanation

DISCUSSION: Histologically, there is metaplastic cartilage arising from the synovium. These lobules of zonates hyaline cartilage are of variable size, are embedded within edematous synovium, and protrude into the joint. The lobules calcify and ossify, leading to the characteristic radiographic appearance. Inflammatory synovitis is not characteristic of synovial chondromatosis. The fluid is clear and serosanguin, not blood tinged.
REFERENCES: Milgram JM: Synovial osteochondromatosis: A histopathological study of thirty cases. J Bone Joint Surg Am 1977;l59:792-801.
Murphy FP, Dahlin DC, Sullivan CR: Articular synovial chondromatosis. J Bone Joint Surg Am 1962;44:77.

Question 99

A year-old man with insulin-dependent diabetes mellitus underwent primary total knee arthroplasty (TKA). A full-thickness skin slough measuring 3 cm by 4 cm developed, with postsurgical exposure of the patellar tendon. No change is observed in the appearance of the wound after 2 weeks of wet-to-dry dressing changes. What is the best next treatment step for the soft-tissue defect?

Explanation

DISCUSSION:
If wound healing does not occur and deep soft tissues such as the patellar tendon are exposed following TKA, local rotational flap is the procedure of choice. The procedure should be performed relatively early after the recognition of a soft-tissue wound-healing problem. In the setting of TKA, the gastrocnemius muscle is an excellent source of flaps for wound coverage of the proximal tibia.

Question 100

The main advantage of surgical repair of an acute Achilles tendon rupture, when compared with nonsurgical management, is reduced

Explanation

DISCUSSION: The literature supports similar clinical outcomes after surgical and nonsurgical methods. The chief difference lies in the complications between the groups. Surgical patients experience more wound problems but a significantly lower rerupture rate. Although suturing the tendon allows earlier mobility, the tendon healing time is unchanged. Nonsurgical methods are less expensive to provide.
REFERENCES: Maffulli N: Rupture of the Achilles tendon. J Bone Joint Surg Am 1999;81:1019-1036.
Cetti R, Christensen SE, Ejsted R, Jensen NM, Jorgensen U: Operative versus nonoperative treatment of Achilles tendon rupture: A prospective randomized study and review of the literature. Am J Sports Med 1993;21:791-799.
Nistor L: Surgical and non-surgical treatment of Achilles tendon rupture. J Bone Joint Surg Am 1981;63:394-399.

Full Question & Answer Text (for Search Engines)

Question 1:

Options:

Galvanic
Pitting
Fretting
Crevice

Correct Answer: Fretting

Explanation:

Question 2:

Bioabsorbable polymers are used in a wide range of orthopaedic devices, including anchors, staples, pins, plates, and screws. What is the primary drawback for bioabsorbable implants?

Options:

High cost
Increased rates of infection
High elastic modulus
Brittleness
Foreign body reaction

Correct Answer: Foreign body reaction

Explanation:

DISCUSSION: A number of bioabsorbable polymers are used in orthopaedic applications, and all have in common reports of foreign body reactions, which occur in more than 50% of patients in some series. In general, the high cost of these polymers is offset by the elimination of a second surgery to remove the implant. Bioabsorbable polymers are low strength in comparison to metallic alloys but of sufficient strength for many orthopaedic applications. The elastic modulus is not as high as many other orthopaedic biomaterials, making them suitable for applications where lower stiffness is an asset.
REFERENCES: Ambrose CG, Clanton TO: Bioabsorbable implants: Review of clinical experience in orthopedic surgery. Ann Biomed Eng 2004;32:171-177.
Bergsma JE, de Bruijn WC, Rozema FR, et al: Late degradation tissue response to poly
(L-lactide) bone plates and screws. Biomaterials 1995;16:25-31.

Question 3:

In revision total hip arthroplasty, an acetabular reconstruction cage is best indicated for which of the following patterns of bone loss?

Options:

Enlarged acetabular rim
Cavitary central defect
Superior migration of 2 cm
Deficient anterior wall
Pelvic discontinuity

Correct Answer: Pelvic discontinuity

Explanation:

Question 4:

In an effort to reduce costs, a limited MRI sequence is planned to detect a possible occult hip fracture. What is the anticipated fracture signal?

Options:

Bright on T 1 and T 2
Dark on T 1 and T 2
Dark on T 1 , bright on T 2
Bright on T 1 , dark on T 2
Enhancement by gadolinium

Correct Answer: Dark on T 1 , bright on T 2

Explanation:

DISCUSSION: At present, radiologists perform multiple MRI images to rule out all possible diagnoses. The ability to specify the anticipated changes on MRI should become more important as a means of reducing costs. MRI is sensitive to changes in free water (or hemorrhage) and thus this will appear dark on T
1
and bright on T
2
.
REFERENCES: Miller MD: Review of Orthopaedics, ed 3. Philadelphia PA, WB Saunders, 2000, p 116.
Guanche CA, Kozin SH, Levy AS, et al: The use of MRI in the diagnosis of occult hip fractures in the elderly: A preliminary review. Orthopedics 1994;17:327-330.

Question 5:

What type of injury is considered the major mechanism of cervical fracture, dislocation, and quadriplegia in contact sports and diving?

Options:

Flexion
Extension
Flexion-compression
Flexion-distraction
Flexion-rotation

Correct Answer: Flexion-compression

Explanation:

Question 6:

- A 14-year-old patient who has homocystinuria and is Risser 3 is referred for surgical treatment of scoliosis. In addition to the usual risks associated with posterior spinal fusion, the family should be advised that the patient ‘s underlying condition significantly increases the perioperative risk of

Options:

Spinal pseudoarthrosis
Spinal cord traction injury with paralysis
Arterial and venous thromboses
Superior mesenteric artery syndrome
Crankshaft phenomenon

Correct Answer: Arterial and venous thromboses

Explanation:

Question 7:

Options:

Allergic metal synovitis
Aseptic loosening of the acetabular component
Septic loosening of the acetabulum
Deconditioning following hip arthroplasty
Iliopsoas tendinitis

Correct Answer: Septic loosening of the acetabulum

Explanation:

DISCUSSION: The difference in the clinical results combined with the laboratory findings points to infection. While there is a significant risk of false-positive findings with aspiration, the fact that two successive aspirations grew the same organism strongly suggests infection. The radiograph shows that there is more radiolucency around the left acetabular component than the right component.
REFERENCES: White RE: Evaluation of the painful total hip arthroplasty, in Callaghan JJ, Rosenberg AG, Rubash HE (eds): The Adult Hip. Philadelphia, PA, Lippincott-Raven, 1998,
vol 2, pp 1377-1385.
Barrack RL, Harris WH: The value of aspiration of the hip joint before revision total hip arthroplasty. J Bone Joint Surg Am 1993;75:66-76.

Question 8:

Options:

MRI of her lumbar spine
Six weeks of physical therapy and anti-inflammatory medication
Determine the patients ankle brachial index
Cervical Spine MRI
Lumbar Epidural Injection

Correct Answer: MRI of her lumbar spine

Explanation:

Question 9:

Options:

semiconstrained total elbow arthroplasty.
ulnohumeral arthroplasty and anterior and posterior capsular releases.
closed reduction and external fixation.
open reduction, heterotopic bone excision, anterior and posterior capsular releases, and a hinged elbow fixator.
open reduction, heterotopic excision, anterior and posterior capsular releases, and pin fixation across the joint for 3 weeks.

Correct Answer: open reduction, heterotopic bone excision, anterior and posterior capsular releases, and a hinged elbow fixator.

Explanation:

Question 10:

Figure 36 shows the radiograph of a patient who has hip pain and is unable to ambulate. What is the most appropriate management for this patient?

Options:

Bisphosphonates
Protected weight bearing
Open reduction and internal fixation
Revision total hip arthroplasty
Resection arthroplasty

Correct Answer: Revision total hip arthroplasty

Explanation:

DISCUSSION: The patient has a periprosthetic fracture of the greater trochanter - Vancouver A. The reason for the fracture of the greater trochanter is the extensive periarticular osteolysis that has occurred as a result of polyethylene wear. The latter is demonstrated by eccentric seating of the large femoral head in the acetabulum. The most appropriate management is to reverse the osteolysis process, which involves exchange of the acetabular liner with or without revision of the other components depending on their fixation and position. The greater trochanter can also be fixed during revision surgery.
REFERENCES: Duncan CP, Masri BA: Fractures of the femur after hip replacement. Instr Course Lect 1995;44:293-304.
Parvizi J, Rapuri VR, Purtill JJ, et al: Treatment protocol proximal femoral periprosthetic fractures. J Bone Joint Surg Am 2004;86:8-16.

Question 11:

Figures 2a and 2b show the radiographs of a 72-year-old man with aseptic loosening of the tibial component of his total knee arthroplasty. Optimal management should include

Options:

tibial revision only, without stems or augmentations.
tibial revision only, with stems and augmentations.
revision of the tibial and femoral components, without stems or augmentations.
revision of the tibial and femoral components, with stems and augmentations.
primary arthrodesis.

Correct Answer: revision of the tibial and femoral components, with stems and augmentations.

Explanation:

DISCUSSION: The radiographs show massive subsidence of the lateral side of the tibia with severe tibial bone loss and a fractured proximal fibula. Reconstruction should consist of a large metal or bony lateral tibial augmentation, and a stem long enough to bypass the defect is required. The femoral and tibial components are articulating without any remaining polyethylene medially; therefore, the femoral component is damaged and needs revision.
The insertions of the lateral ligaments are absent, thereby rendering the lateral side of the knee predictably unstable. Also, the large valgus deformity compromises the medial collateral ligament. The posterior cruciate ligament is also likely to be deficient with this much tibial bone destruction. The patient requires a posterior stabilized femoral component at the minimum, and possibly a constrained femoral component. Retention of the femoral component, even though it may be well-fixed, jeopardizes the outcome.
REFERENCES: Lotke PA, Garino JP: Revision Total Knee Arthroplasty. New York, NY, Lippincott-Raven, 1999, pp 137-250.
Insall JN, Windsor RE, Scott WN, et al: (eds): Surgery of the Knee, ed 2. New York, NY, Churchill Livingstone, 1993, pp 935-957.
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 339-365.

Question 12:

A 14-year-old girl has had progressive heel pain for the past several months. Based on the radiograph, MRI scan, and biopsy specimens shown in Figures 37a through 37d, treatment should include

Options:

observation.
wide resection.
radiation therapy.
extended curettage.
chemotherapy.

Correct Answer: extended curettage.

Explanation:

DISCUSSION: An aneurysmal bone cyst is a benign, locally destructive lesion of bone. Most are seen in patients in the second decade of life. The clinical presentation varies, but most patients have pain, tenderness, swelling, and/or pathologic fracture. Radiographs show a radiolucent lesion sometimes with expansile remodeling of the cortex. MRI best detects the commonly seen fluid-fluid levels associated with this lesion. Histologic findings include
blood-filled spaces with bland fibrous connective tissue septa. The stroma has histiocytes, fibroblasts, scattered giant cells, hemosiderin, and occasional inflammatory cells. Treatment of these lesions consists of extended curettage, plus or minus the use of adjuvants (liquid nitrogen, phenol, argon beam coagulation), and finally filling the bone void (allograft or other bone substitute).
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.
Ramirez AR, Stanton RP: Aneurysmal bone cyst in 29 children. J Pediatr Orthop 2002;22:533-539.

Question 13:

Options:

observation and regular follow-up.
a custom-molded thoracolumbar orthosis.
anterior spinal fusion from T10 to L4.
anterior and posterior spinal fusion from T10 to L4.
posterior spinal fusion from T4 to L4.

Correct Answer: anterior spinal fusion from T10 to L4.

Explanation:

Question 14:

Which lower extremity muscle is first weakened in Charcot-Marie-Tooth (CMT) disease?

Options:

Peroneus brevis
Peroneus longus
Foot intrinsics
Tibialis anterior

Correct Answer: Foot intrinsics

Explanation:

DISCUSSION
Although many of the lower extremity muscles may be affected in CMT, those innervated by the longest axons have been shown to be affected first. In the lower extremity the muscles innervated by the longest axons are the intrinsic foot muscles. The tibialis anterior and the peroneus brevis may be severely affected but not before the foot intrinsics. The peroneus longus typically is spared, resulting in the cavus.
RECOMMENDED READINGS
Pareyson D, Marchesi C. Diagnosis, natural history, and management of Charcot-Marie-Tooth disease. Lancet Neurol. 2009 Jul;8(7):654-67. Review. PubMed PMID: 19539237.
View
Abstract at PubMed
Wenz W, Dreher T. Charcot-Marie-Tooth disease and the cavovarus foot. In: Pinzur MS, ed. Orthopaedic Knowledge Update: Foot and Ankle 4. Rosemont, IL: American Academy of Orthopaedic Surgeons; 2008:291-306.
CLINICAL SITUATION FOR QUESTIONS 60 THROUGH 63
Figure 60 is the standing radiograph of a 27-year-old man who played football throughout his teen years. During those years, he noted that he had less mobility of his left foot and ankle. He twisted his left foot and ankle 8 months ago and has tried over-the-counter nonsteroidal anti-inflammatory drugs and a brace. He now has pain and edema in the left sinus tarsi area. Upon examination the following arcs of motion are identified: ankle dorsiflexion-right, 5 degrees/left, 5 degrees; ankle plantar flexion-right, 30 degrees/left 30 degrees; foot inversion-right, 10 degrees/left, 5 degrees; foot eversion-right, 10 degrees/left 5 degrees.

Question 15:

Options:

Synovial chondromatosis
Pigmented villonodular synovitis
Synovial cell sarcoma
Tuberculosis
Chondrosarcoma

Correct Answer: Synovial chondromatosis

Explanation:

Question 16:

During a posterior cruciate ligament (PCL)-retaining total knee arthroplasty, a critical principle to remember is to

Options:

accurately tension the PCL.
use bony resection to adjust the joint line.
maintain a small amount of residual deformity.
use intraoperative fluoroscopy to ensure femoral roll back.

Correct Answer: accurately tension the PCL.

Explanation:

Question 17:

Treatment of this fracture should consist of

Options:

closed reduction, limited immobilization (1-2 weeks), and early functional rehabilitation.
limited immobilization in a long-arm cast (4 weeks) and early functional rehabilitation.
open reduction and internal fixation.
open reduction, capsular repair, and suture fixation of the bony fragment and ligament.

Correct Answer: open reduction and internal fixation.

Explanation:

DISCUSSION
Varus posteromedial rotatory instability is a complex injury pattern that starts with varus stress resulting in a fracture of the anteromedial coronoid. The anterior MCL attaches to the sublime tubercle, which is part of the anteromedial coronoid facet. The posterior MCL attaches to the posterior medial aspect of the ulna. The radial collateral and lateral ulnar collateral attach to the ulna at the crista supinatoris. The bony landmark is the sublime tubercle; as noted above, the crista supinatoris is lateral on the ulna. The radial notch is also lateral and is the articulation between the proximal ulna and proximal radius. The anteromedial coronoid facet is part of the coronoid, which extends more lateral and anterior than the anteromedial facet. The anteromedial facet represents the critical weight-bearing portion of the ulnohumeral joint. Damage to this structure causes posteromedial subluxation that often results in severe progressive arthritis. The coronoid is the larger structure of which the anteromedial coronoid facet is a portion. The posteromedial coronoid facet does not appear to be critical in weight bearing. The radial notch is not associated with increased stress with weight bearing. The treatment of displaced fractures of this structure is open reduction and internal fixation utilizing buttress plating. Closed treatment is acceptable only for nondisplaced fractures with appropriate radiographic follow-up. Suture fixation is not advocated because of inadequate strength.
RECOMMENDED READINGS
Pollock JW, Brownhill J, Ferreira L, McDonald CP, Johnson J, King G. The effect of anteromedial facet fractures of the coronoid and lateral collateral ligament injury on elbow stability and kinematics. J Bone Joint Surg Am. 2009 Jun;91(6):1448-58. doi: 10.2106/JBJS.H.00222.
Sanchez-Sotelo J, O'Driscoll SW, Morrey BF. Anteromedial fracture of the coronoid process of the ulna. J Shoulder Elbow Surg. 2006 Sep-Oct;15(5):e5-8. Epub 2006 Jul 26. Erratum in: J Shoulder Elbow Surg. 2007 Jan-Feb;16(1):127. PubMed PMID: 16979044.

Question 18:

Which of the following methods is effective in correcting recurrent dislocation following total hip arthroplasty?

Options:

Lateralization of the greater trochanter without advancement
Use of a shorter neck length
Use of a constrained acetabular component
Use of a small diameter head
High cup abduction angle

Correct Answer: Use of a constrained acetabular component

Explanation:

Question 19:

A 9-year-old girl has pain over the fifth toe that is aggravated by shoe wear. Clinical photographs are shown in Figures 28a and 28b. Treatment of this deformity should consist of

Options:

extensor digitorum longus tenotomy.
extensor digitorum longus tenotomy with dorsal fifth metatarsophalangeal (MTP) joint capsulotomy.
dorsal V-Y plasty for skin contracture, combined with extensor digitorum longus tenotomy and dorsal fifth MTP capsulotomy.
a dorsal and plantar racquet-shaped incision around the fifth toe, combined with extensor digitorum longus tenotomy and circumferential fifth MTP joint release (Butler procedure).
plantar proximal phalangeal resection.

Correct Answer: a dorsal and plantar racquet-shaped incision around the fifth toe, combined with extensor digitorum longus tenotomy and circumferential fifth MTP joint release (Butler procedure).

Explanation:

DISCUSSION: The major obstacle to overcome in the surgical treatment of this cock-up deformity is recurrence. Dorsal releases can be performed; however, chronic dislocation of the fifth MTP joint usually needs to be addressed with plantar release as well. Chronic dorsal soft-tissue contractures may be overcome with translation of the toe into a plantar-based incision, as described originally by Cockin and accredited to Butler. This is the treatment of choice. Resection of the proximal phalanx improves symptoms but induces a secondary deformity; this procedure is usually reserved for skeletally mature individuals.
REFERENCES: Black GB, Grogan DP, Bobechko WP: Butler arthroplasty for correction of adducted fifth toe: A retrospective study of 36 operations between 1968 and 1982. J Pediatr Orthop 1985;5:439-441.
Paton RW: V-Y plasty for correction of varus fifth toe. J Pediatr Orthop 1990;10:248-249.
Coughlin MJ, Mann RA: Lesser toe deformities, in Coughlin MJ, Mann RA (eds): Surgery of the Foot and Ankle, ed 5. St Louis, MO, Mosby, 1986, pp 132-157.

Question 20:

Options:

Previous surgical approach
Previous tourniquet time
Implant model
Presence of an anterior femoral notch

Correct Answer: Implant model

Explanation:

DISCUSSION
Treatment of periprosthetic supracondylar femoral fractures is complex and may involve the use of a retrograde intramedullary femoral nail or locked or unlocked femoral plate. Knowledge of certain measurements specific to the model of the implant, specifically to the minimal intercondylar distance and the position of the notch on the femoral component in relation to the intramedullary canal, is crucial when choosing a retrograde nail over a locked femoral plate. Although the surgical approach, presence of an anterior femoral notch, and previous tourniquet time are interesting to consider, none of these factors would preclude the ability to proceed with femoral intramedullary nailing.
CLINICAL SITUATION FOR QUESTIONS 128 THROUGH 130
Figure 128 is the radiograph of a 78-year-old nursing home resident who has hypertension and peripheral vascular disease. He has developed acute severe hip pain 20 years after undergoing a cementless total hip arthroplasty (THA) and subsequent revision for instability. He was previously ambulatory with a walker and now can no longer ambulate. His erythrocyte sedimentation rate is 8 mm/h (reference range [rr], 0-20 mm/h) and C-reactive protein level is

Question 21:

Suprapatellar intramedullary nailing for tibia fractures when compared to infrapatellar nailing is associated with

Options:

decreased knee range of motion.
increased incidence of malalignment.
less anterior knee pain.
changes in the patellofemoral joint.

Correct Answer: less anterior knee pain.

Explanation:

Question 22:

Radiographs of a pediatric patient reveal a suspected osteosarcoma of the distal femur. Additional staging studies should consist of

Options:

a radiograph and CT of the chest and a bone scan.
a radiograph and MRI of the primary tumor.
CT of the abdomen and pelvis.
CT of the abdomen, chest, and pelvis, radiographs of the chest and primary tumor, MRI of the primary tumor, and a bone scan.
CT of the chest, radiographs of the chest and primary tumor, MRI of the primary tumor, and a bone scan.

Correct Answer: CT of the chest, radiographs of the chest and primary tumor, MRI of the primary tumor, and a bone scan.

Explanation:

Question 23:

Staged open reduction and internal fixation with free flap soft tissue reconstruction is the most appropriate definitive treatment method for which of the following tibial injuries?

Options:

Type IIIB intra-articular distal tibia fracture
Type IIIB segmental midshaft tibia fracture
Type IIIB transverse midshaft tibia fracture
Type IIIB Schatzker I proximal tibia fracture
Type IIIB Schatzker IV proximal tibia fracture

Correct Answer: Type IIIB intra-articular distal tibia fracture

Explanation:

Question 24:

Options:

Advanced degenerative disk disease with facet arthrosis at L5-S1
Decreased T2 signal in the L5-S1 disk with normal facet joints
Previous laminectomy at L5-S1
Fixed tilt of L5 with severe unilateral facet arthrosis
Spondylolysis bilaterally at L5

Correct Answer: Decreased T2 signal in the L5-S1 disk with normal facet joints

Explanation:

Question 25:

When performing a gastrocnemius recession, what structure should be protected?

Options:

Tibial nerve
Sural artery
Plantaris
Posterior tibial artery
Sural nerve

Correct Answer: Sural nerve

Explanation:

DISCUSSION: When performing a gastrocnemius slide at the tendinous portion of the gastrocnemius insertion, the sural nerve and saphenous vein, which tend to run midline posterior at this level, must be protected and retracted laterally. An anatomic study of the sural nerve at this level localized the nerve superficial to the deep fascia overlying the gastrocnemius in 42.5% of the cases; deep to the superficial fascia in 57.5% of the cases, and directly applied to the gastrocnemius tendon in 12.5% of cases.
REFERENCES: Pinney SJ, Sangeorzan BJ, Hanen ST Jr: Surgical anatomy of the gastrocnemius resection (Strayer procedure). Foot Ankle Int 2004;25:247-250.
Hansen ST Jr: Functional Reconstruction of the Foot and Ankle. Philadelphia, PA, Lippincott Williams & Wilkins, 2000, pp 415-417.

Question 26:

Options:

Correction of the thoracolumbar curve
Sagittal balance
Coronal balance
Correction of the thoracic curve
Shoulder balance

Correct Answer: Correction of the thoracic curve

Explanation:

Sagittal balance is the most reliable predictor of clinical symptoms and HRQL outcomes on the SRS 29, SF-12, and Oswestry Disability Index. Coronal balance, shoulder balance, curve magnitude, and degree of curve correction are less critical in determining clinical symptoms and outcomes.
(SBQ12SP.24) A 39-year-old man presents to clinic with a 3-week history of low back pain that radiates to the right lower extremity. On examination, he has mildly decreased sensation over the dorsum of the foot and positive straight leg raise on the right side. MRI images are shown in Figure A and B. Which of the following is true regarding this patient's condition?
Review Topic
Nonoperative management with NSAIDS and physical therapy is effective for 50% of patients
Surgical treatment is indicated in patients with diminished sensation
Surgical treatment is equivalent to nonoperative management in terms of pain and function
Good surgical outcome is associated with mainly back complaints
Size of disc herniations typically decrease over time without surgical intervention
The patient is presenting with a lumbar disc herniation at the L4-L5 level. The size of disc herniations decrease in most patients over time without surgical intervention.
Lumbar disc herniations are the result of recurrent torsional strain, which leads to small tears of the annulus fibrosus, ultimately allowing herniation of the nucleus pulposis. First line treatment consists of NSAIDS, muscle relaxants and physical therapy and is effective in 90% of patients. Second line treatment typically involves epidural and selective nerve root corticosteroid injections. Microdiscectomy is reserved for patients with more than 6 weeks of disabling pain that has failed nonoperative management, progressive weakness, or cauda equina syndrome.
In the Spine Patient Outcomes Research Trial (SPORT), Weinstein et al. investigated patient outcomes and satisfaction after operative and nonoperative management of lumbar disc herniations. While the randomized arm of the study did show statistically significant differences in the intent-to-treat analysis due to significant crossover of patients, the observational cohort revealed a significant improvement in pain, function, and disability for patients treated with surgery versus nonoperative measures.
Benson et al. looked at the natural history of massive herniated discs in 37 patients with 7-year follow up. They found a more than 60% reduction in disc size over this time period. Reduction in disc size did not correlate with clinical improvement.
Figure A and B are sagittal and axial T2 MRI images, respectively, showing a right sided lumbar disc herniation at the L4-L5 level.
Incorrect Answers:

Question 27:

Options:

placement of a chest tube.
insertion of a large gauge needle into the second intercostal space.
cardiopulmonary resuscitation.
administration of adrenaline.
immediate transfer to the emergency department.

Correct Answer: insertion of a large gauge needle into the second intercostal space.

Explanation:

Question 28:

Regarding the role of the orthopaedic surgeon in addressing domestic and family violence, all of the following statements are true EXCEPT:

Options:

Report all cases of child abuse, as this is required by all states
Report all cases of adult spousal or intimate partner abuse, as this is required by all states
Hospitalize elderly victims who are in immediate danger and help develop a plan to ensure their safety
Advocate for appropriate legislation and public policy on violence and abuse related to health care
Orthopedic surgeons are responsible for knowing the reporting laws and procedures for suspected abuse

Correct Answer: Report all cases of child abuse, as this is required by all states

Explanation:

Question 29:

Options:

CT
Limited bone scan
MRI
Joint aspiration
Functional capacity examination

Correct Answer: MRI

Explanation:

Question 30:

The fracture shown in Figure 32 is strongly indicative of what diagnosis?

Options:

Osteogenesis imperfecta
Vitamin D-resistant rickets
Lead toxicity
Child abuse
Osteomyelitis

Correct Answer: Child abuse

Explanation:

Question 31:

A 6-year-old boy has leg pain. A radiograph, MRI, CT, and bone scans, and a biopsy specimen are shown in Figures 14a through 14e. What is the most likely diagnosis?

Options:

Ewing’s sarcoma
Osteomyelitis
Osteosarcoma
Eosinophilic granuloma
Fibrous dysplasia

Correct Answer: Osteomyelitis

Explanation:

Question 32:

Options:

immediate hospital admission and surgery because of the risk of paralysis.
surgery within 24 hours.
surgery within the next several days.
elective surgery at the next available surgical date.
additional nonsurgical management.

Correct Answer: additional nonsurgical management.

Explanation:

Question 33:

Options:

progressive ulnar neuropathy.
a decision to enter the Major League Baseball (MLB) draft.
pain with resisted wrist flexion.
failure to improve after prolonged nonsurgical treatment.

Correct Answer: failure to improve after prolonged nonsurgical treatment.

Explanation:

Question 34:

Options:

Alcoholism
Drug abuse
Down syndrome
Diabetes mellitus
Idiopathic scoliosis

Correct Answer: Diabetes mellitus

Explanation:

DISCUSSION: The history, physical examination, and radiographic findings are consistent with type IV sacral agenesis or caudal regression syndrome. These children are born with no lumbar spine or sacrum. The T12 vertebra is often prominent posteriorly. Popliteal webbing and knee flexion contractures are common with this diagnosis. There is a higher incidence of this diagnosis when the mother has diabetes mellitus. Maternal drug abuse and alcoholism can produce phenotypically unique children but without the findings described here. Maternal idiopathic scoliosis is not associated with caudal regression syndrome.
REFERENCES: Chan BW, Chan KS, Koide T, et al: Maternal diabetes increases the risk of caudal regression caused by retinoic acid. Diabetes 2002;51:2811-2816.
Zaw W, Stone DG: Caudal regression syndrome in twin pregnancy with type II diabetes.
J Perinatol 2002;22:171-174.

Question 35:

Based on the MRI scan shown in Figure 6, the abnormal signal is seen in what carpal bone?

Options:

Triquetrum
Lunate
Hamate
Trapezium
Trapezoid

Correct Answer: Trapezoid

Explanation:

Question 36:

A 36-year-old nurse has had redness, pain, and small vesicles on the pulp of her middle finger for the past 3 days. Management should consist of

Options:

observation.
marsupialization of the nail fold.
application of copper sulfate.
application of calcium gluconate.
incision and drainage of the pulp.

Correct Answer: observation.

Explanation:

Question 37:

During the early swing phase of the normal gait cycle, what lower extremity muscle is primarily contracting?

Options:

Tibialis posterior
Tibialis anterior
Vastus medialis
Adductor longus
Gastrocnemius

Correct Answer: Tibialis anterior

Explanation:

DISCUSSION: Electromyography during walking reveals the tibialis anterior muscle is active during early swing, allowing the foot to clear the ground. All of the other muscles are quiet, as the limb moves forward through space with minimal muscular effort. The other muscles are primarily active during weight acceptance or push-off.
REFERENCES: Gage JR: An overview of normal walking. Instr Course Lect 1990;39:291-303.
Wootten ME, Kadaba MP, Cochran GV: Dynamic electromyography II: Normal patterns during gait. J Orthop Res 1990;8:259-265.

Question 38:

What is the most common donor site complication following a free vascularized fibular graft for osteonecrosis of the femoral head?

Options:

Sensory deficit
Motor deficit
Flexor hallucis longus contracture
Deep venous thrombosis
Fibular fracture

Correct Answer: Sensory deficit

Explanation:

Question 39:

Options:

Continued skin traction
Skeletal traction of both femurs
External fixation of both femurs
Intramedullary nailing of one femur and external fixation and delayed nailing for the other femur
Intramedullary nailing of both femurs

Correct Answer: Intramedullary nailing of both femurs

Explanation:

DISCUSSION: Although this patient had a hemothorax, the bleeding has stopped and he has been resuscitated to a euvolemic status with a small base deficit and good urine output. External fixation of both femurs is an option but an unnecessary step in the treatment algorithm.
REFERENCES: Nork SE, Agel J, Russell GV, et al: Mortality after reamed intramedullary nailing of bilateral femur fractures. Clin Orthop Relat Res 2003;415:272-278.
Pape HC, Zelle BA, Hildebrand F, et al: Reamed femoral nailing in sheep: Does irrigation and aspiration of intramedullary contents alter the systemic response? J Bone Joint Surg Am 2005;87:2515-2522.

Question 40:

Options:

Surgical repair of the Bankart lesion
Exploration of the axillary nerve
MRI neurography
Repeat EMG studies
Continued observation and physical therapy

Correct Answer: Repeat EMG studies

Explanation:

Question 41:

Options:

The number of months he plays per year
The number of pitches he throws per game
The number of games he plays per week
His fastball speed
Playing in another position once being relieved of pitching

Correct Answer: Playing in another position once being relieved of pitching

Explanation:

Question 42:

Options:

a base plate with an offset tibial stem attachment.
a bone ingrowth surface on the augment.
a nonstemmed tibial base plate.
allograft bone instead of metal augments.
bone cement to smooth the outline of the proximal medial tibia.

Correct Answer: a base plate with an offset tibial stem attachment.

Explanation:

DISCUSSION: The problem with this reconstruction is the medial protrusion of the base plate. The use of a base plate with an offset stem can prevent the protrusion and thus the impingement and pain. Allograft bone or smoothing the outline with cement would be just as prominent and likely to cause pain. An ingrowth surface may improve soft-tissue attachment but would still leave the implant protruding medially and likely to cause pain. A nonstemmed tibial base plate would lead to less medial protrusion but at the expense of a smaller area for load carriage on the proximal tibia.
REFERENCE: Gustke K: Cemented tibial stems are not requisite in revision. Orthopedics 2004;27:991-992.

Question 43:

Options:

Immobilization/casting
Rest, limited weight bearing, and repeat radiographs in 4 weeks
MRI of the femur
Biopsy
Chemotherapy

Correct Answer: MRI of the femur

Explanation:

DISCUSSION: The radiographs show a very ill-defined, aggressive, moth-eaten bony destruction involving the distal left femoral diaphysis just above the metaphyseal junction. The differential diagnosis includes Ewing’s sarcoma, osteosarcoma, lymphoma of bone, eosinophilic granuloma, osteomyelitis, and others. MRI would further define the lesion, and soft-tissue and intramedullary extension. There is aggressive periosteal reaction in the posteromedial aspect of the adjacent lesion with some multilayered components in the distal interface of the periosteum. The lateral radiograph shows cortical penetration and irregular periosteal reaction of the posterior margin, suggesting some posterior soft-tissue extension at this site as well.
REFERENCES: Gebhardt MC, Ready JE, Mankin HJ: Tumors about the knee in children. Clin Orthop Relat Res 1990;255:86-110.
Menendez LR (ed): Orthopaedic Knowledge Update: Musculoskeletal Tumors. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 175-186.

Question 44:

Options:

wrist x-ray not initially obtained
x-ray obtained, but MRI necessary for diagnosis not obtained
forearm x-ray initially obtained did not show fracture
CT initially performed, but no 3-D images reconstructed
wrist x-ray initially obtained did not show fracture

Correct Answer: wrist x-ray not initially obtained

Explanation:

Question 45:

Options:

Single posterior Y plate
Single medial plate with bicortical locking screws
Dual plating with medial and posterolateral LC-DCP
Dual plating with medial and posterolateral one third tubular plates
Dual plating with medial and lateral LC-DCP

Correct Answer: Dual plating with medial and lateral LC-DCP

Explanation:

Question 46:

A 5-year-old boy has a deformity of his right arm after falling from a jungle gym. A radiograph is shown in Figure 37. Management should consist of

Options:

closed reduction of the ulna and transcapitellar pinning of the radial head.
closed reduction of the ulna and radial head dislocation.
closed reduction of the ulna and annular ligament repair.
open reduction of the radius and plating of the ulna.
open reduction of the ulna and immobilization in an extension cast.

Correct Answer: closed reduction of the ulna and radial head dislocation.

Explanation:

Question 47:

Options:

Sural
Deep peroneal
Medial plantar
Posterior tibial

Correct Answer: Sural

Explanation:

Question 48:

Options:

Retain the components and implant a tibial strut allograft
Revise the tibial component with a metaphyseal cone and metaphyseal uncemented stem
Revise the tibial component with a metaphyseal cone and a press-fit diaphyseal-engaging stem
Revise the tibial component with a long cemented diaphyseal-engaging stem

Correct Answer: Revise the tibial component with a metaphyseal cone and a press-fit diaphyseal-engaging stem

Explanation:

Question 49:

- Which of the following neurovascular structures is at greatest risk during the introduction of acetabular component fixation screws during total hip replacement?

Options:

Sciatic nerve
Superior gluteal artery
Profunda femoris artery
Femoral artery and nerve
External iliac artery and vein

Correct Answer: External iliac artery and vein

Explanation:

Question 50:

The teardrop shape marked with an asterisk in Figure 61 represents what anatomic structure?

Options:

Anterior superior iliac spine
Sciatic buttress
A column of bone running from the anterior inferior iliac spine (AIIS) to the posterior superior iliac spine (PSIS)
The most superior portion of the roof of the acetabulum
Iliopectineal line

Correct Answer: A column of bone running from the anterior inferior iliac spine (AIIS) to the posterior superior iliac spine (PSIS)

Explanation:

DISCUSSION: The teardrop can be visualized on the obturator outlet view of the pelvis and represents a thick column of bone that runs from the AIIS to the PSIS. Half pins for eternal fixation frames or screws can be inserted into this column for fixation of fractures.
REFERENCES: Gardner MJ, Nork SE: Stabilization of unstable pelvic fractures with supra-acetabular compression external fixation. J Orthop Trauma 2007;21:269-273.
Haidukewych GJ, Kumar S, Prpa B: Placement of half-pins for supra-acetabular external fixation: An anatomic study. Clin Orthop Relat Res 2003;411:269-273.
Kim WY, Hearn TC, Seleem O, et al: Effect of pin location on stability of pelvic external fixation. Clin Orthop Relat Res 1999;361:237-244.

Question 51:

Central cord syndrome would most likely be seen in which of the following patients? Review Topic

Options:

year-old male following hyperextension cervical injury
year-old male following penetrating trauma to the neck
year-old male following hyperflexion cervical injury
year-old male following surgical aortic aneurysm repair
year-old male without a traumatic mechanism

Correct Answer: year-old male without a traumatic mechanism

Explanation:

Question 52:

Options:

Bisphosphonates
Calcitonin
Parathyroid hormone
Vitamin D and calcium
Methotrexate

Correct Answer: Bisphosphonates

Explanation:

DISCUSSION: McCune-Albright syndrome is the combination of polyostotic fibrous dysplasia, café-au-lait lesions, and endocrine dysfunction. The most common endocrine presentation is precocious development of secondary sexual characteristics. Compared with bone lesions in patients without polyostotic disease, the skeletal lesions in patients with the syndrome tend to be larger, more persistent, and associated with more complications. Bisphosphonate therapy has been shown in several studies to decrease the pain associated with the skeletal lesions of fibrous dysplasia.
REFERENCES: DiCaprio MR, Enneking WF: Fibrous dysplasia: Pathophysiology, evaluation and treatment. J Bone Joint Surg Am 2005;87:1848-1864.
Zacharin M, O’Sullivan M: Intravenous pamidronate treatment of polyostotic fibrous dysplasia associated with McCune Albright syndrome. J Pediatr 2000;137:403-409.

Question 53:

What is the most frequent location of entrapment of the deep peroneal nerve?

Options:

Tendon of the extensor hallucis brevis
Inferior extensor retinaculum
Osteophytes of the talonavicular joint
Os intermetatarseum
Base of the fifth metatarsal

Correct Answer: Inferior extensor retinaculum

Explanation:

DISCUSSION: The most frequently described entrapment of the deep peroneal nerve is the anterior tarsal tunnel syndrome. This syndrome refers to entrapment of the deep peroneal nerve under the inferior extensor retinaculum. Entrapment can also occur as the nerve passes under the tendon of the extensor hallucis brevis. Compression by underlying dorsal osteophytes of the talonavicular joint and an os intermetatarseum (between the bases of the first and second metatarsals) have previously been described in runners.
REFERENCES: Kopell HP, Thompson WA: Peripheral entrapment neuropathies of the lower extremity. N Engl J Med 1960;262:56-60.
Schon LC, Mann RA: Diseases of the nerves, in Coughlin MJ, Mann RA, Saltzman CL (eds): Surgery of the Foot and Ankle, ed 8. Philadelphia, PA, Mosby-Elsevier, 2007, vol 1, pp 675-677.

Question 54:

Options:

electrical stimulation.
a Charleston bending brace at night.
an extension-type spinal orthosis.
posterior spinal fusion with instrumentation.
anterior spinal release and posterior spinal instrumentation.

Correct Answer: an extension-type spinal orthosis.

Explanation:

Question 55:

Which of the following nerves is most commonly injured during arthroscopy of the ankle?

Options:

Sural
Saphenous and its branches
Posterior tibial and its branches
Deep peroneal and its branches
Superficial peroneal and its branches

Correct Answer: Superficial peroneal and its branches

Explanation:

Question 56:

Options:

long leg cast immobilization for 6 weeks.
open reduction and internal fixation.
activity restrictions and nonsteroidal anti-inflammatory drugs.
cessation of sports for 6 to 18 months.
diagnostic arthroscopy.

Correct Answer: activity restrictions and nonsteroidal anti-inflammatory drugs.

Explanation:

Question 57:

Storage of musculoskeletal allografts by cryopreservation is achieved by

Options:

replacing water in the tissue with alcohol to a moisture level of 5% and then using a vacuum process to remove the alcohol from the tissue.
maintaining maximum cellular viability of fresh tissue without long-term storage.
using chemicals to remove cellular water and controlled rate freezing to prevent ice crystal formation.
freezing the graft twice and packaging the tissue without solution at minus 80 degrees C.
freezing the graft in water without an antibiotic solution soak during quarantine, with final storage in liquid nitrogen.

Correct Answer: using chemicals to remove cellular water and controlled rate freezing to prevent ice crystal formation.

Explanation:

Question 58:

Options:

Abduction to 90 degrees with maximal external rotation
Forward elevation to 170 degrees with neutral rotation
Cross-body adduction at 90 degrees flexion, with internal rotation
Extension with maximal internal rotation
Flexion to 90 degrees with maximal external rotation

Correct Answer: Abduction to 90 degrees with maximal external rotation

Explanation:

Question 59:

A 17-year-old girl has multidirectional instability of the shoulder. What is the most appropriate initial management? Review Topic

Options:

Immobilization in a sling and swathe
Open capsular shift
Arthroscopic capsular plication
Thermal capsulorrhaphy
Physical therapy and home exercises

Correct Answer: Physical therapy and home exercises

Explanation:

Question 60:

Options:

Amyotrophic lateral sclerosis
Cubital tunnel syndrome
Normal aging
Cervical radiculopathy

Correct Answer: Cervical radiculopathy

Explanation:

Question 61:

Options:

Gradual return to play
Physical therapy program
Custom orthosis
Non-weight-bearing cast
Weight-bearing AP radiograph

Correct Answer: Weight-bearing AP radiograph

Explanation:

DISCUSSION: Differentiating between a midfoot sprain and Lisfranc diastasis is critical in the management of the athlete with an acute injury to the midfoot. Greater than 2 mm of displacement between the first and second metatarsals on a weight-bearing radiograph is an indication for anatomic reduction with internal fixation of the tarsometatarsal joints. If no subluxation is noted, treatment should consist of a non-weight-bearing cast for 6 weeks, followed by a gradual return
to activity.
REFERENCES: Mizel MS, Miller RA, Scioli MW (eds): Orthopaedic Knowledge Update: Foot and Ankle 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1998, pp 39-54.
Chiodo CP, Myerson MS: Developments and advances in the diagnosis and treatment of injuries with the transmetatarsal joint. Orthop Clin North Am 2001;32:11-20.

Question 62:

Options:

Osteosarcoma
Ewing’s sarcoma
Osteochondroma
Chondrosarcoma
Periosteal chondroma

Correct Answer: Osteosarcoma

Explanation:

Question 63:

-A 42-year-old woman has had right wrist pain for 2 years. She tried splint wear and naproxen and has had 3 steroid injections, each time experiencing less relief.

Options:

Examination revealed tenderness at and just proximal to the radial styloid, with pain exacerbated with thumb flexion and wrist ulnar deviation. What
is the best next step in treatment?
Physical therapy
Continued splint wear
Repeat injection into the first dorsal wrist compartment
Incision of the first dorsal wrist compartment at the volar edge
Incision of the first dorsal wrist compartment at the dorsal edge

Correct Answer: Repeat injection into the first dorsal wrist compartment

Question 64:

Options:

acute and transient spinal cord injury.
central cord syndrome.
nerve root avulsion.
Guillain-Barre syndrome.
stinger/burner.

Correct Answer: stinger/burner.

Explanation:

Question 65:

Options:

Increased range of motion and strains at L3-L4
A herniated disk due to the fall
A compression fracture
Development of pseudarthrosis due to failure of the previous fusions
Loosening of the hardware that was used for the previous fusions

Correct Answer: Increased range of motion and strains at L3-L4

Explanation:

Question 66:

Figure 53 shows the arteriogram of a 45-year-old man who has severe vasculitis. What do the findings show?

Options:

A patent ulnar artery and deep palmar arch
A patent ulnar artery and superficial palmar arch
A patent radial artery and deep palmar arch
A patent radial artery and superficial palmar arch
A patent radial artery and an ulnar artery aneurysm

Correct Answer: A patent radial artery and deep palmar arch

Explanation:

DISCUSSION: The arterial supply to the hand is abundant and normally duplicated. The deep palmar arch as shown in this arteriogram typically receives its primary contribution from the radial artery which travels deep to the first dorsal compartment tendons and then returns to the volar aspect of the palm through the first web space. The superficial palmar arch receives its supply from the ulnar artery and is not visualized in this patient.
REFERENCE: Cooney WP, Linscheid RL, Dobyns JH (eds): The Wrist: Diagnosis and Operative Treatment. Philadephia, PA, Mosby-Year Book, 1998, p 110.

Question 67:

Which stress fracture location is reported most frequently among ballet dancers?

Options:

Base of the second metatarsal
Base of the fifth metatarsal
Tibial sesamoid
Central third of the tarsal navicular

Correct Answer: Base of the second metatarsal

Explanation:

DISCUSSION
Stress fractures are a frequent overuse injury among professional ballet dancers. The most common location is at the proximal metaphyseal-diaphyseal junction of the second metatarsal. Repetitive stress injuries and fractures of the tibial sesamoid, tarsal navicular, and base of the fifth metatarsal occur among other athletes.
RECOMMENDED READINGS
O'Malley MJ, Hamilton WG, Munyak J, DeFranco MJ. Stress fractures at the base of the second metatarsal in ballet dancers. Foot Ankle Int. 1996 Feb;17(2):89-94. PubMed PMID: 8919407.
View Abstract at PubMed
Micheli LJ, Sohn RS, Solomon R. Stress fractures of the second metatarsal involving Lisfranc's joint in ballet dancers. A new overuse injury of the foot. J Bone Joint Surg Am. 1985 Dec;67(9):1372-5. PubMed PMID: 4077907.
View Abstract at PubMed
Gehrmann RM, Renard RL. Current concepts review: Stress fractures of the foot. Foot Ankle Int. 2006 Sep;27(9):750-7. Review. PubMed PMID: 17038292.
View Abstract at PubMed

Question 68:

During what phase of the throwing motion is the highest torque measured across the glenohumeral joint?

Options:

Wind-up
Cocking
Early acceleration
Late acceleration
Follow through

Correct Answer: Follow through

Explanation:

Question 69:

Options:

Unicompartmental arthroplasty
Total knee arthroplasty
Lateral closing wedge proximal tibial osteotomy
Medial opening wedge proximal tibial osteotomy
Medial closing wedge supracondylar femoral osteotomy

Correct Answer: Medial closing wedge supracondylar femoral osteotomy

Explanation:

DISCUSSION: Patients with a valgus alignment about the knee can have lateral compartment arthritis. Similar to a high tibial osteotomy, a supracondylar femoral osteotomy is indicated in younger patients who have a more active lifestyle and isolated unicompartmental disease. In this young patient who works in a factory and has a valgus knee, a medial closing wedge supracondylar femoral osteotomy is the treatment of choice. The role of arthroplasty is limited in younger patients.
REFERENCES: Mathews J, Cobb AG, Richardson S, et al: Distal femoral osteotomy for lateral compartment osteoarthritis of the knee. Orthopedics 1998;21:437-440.
Cameron HU, Botsford DJ, Park YS: Prognostic factors in the outcome of supracondylar femoral osteotomy for lateral compartment osteoarthritis of the knee. Can J Surg 1997;40:114-118.

Question 70:

Options:

a rehabilitation program to strengthen his remaining scapular muscles.
a scapular brace to keep his scapula reduced.
scapulothoracic fusion.
pectoralis minor muscle transfer.
latissimus dorsi muscle transfer.

Correct Answer: scapulothoracic fusion.

Explanation:

Question 71:

Options:

Revise the tibial tunnel to be more oblique.
Revise the tibial tunnel to be more posterior.
Convert to a transtibial double-bundle ACL.
Prepare the femoral tunnel via an anteromedial portal or two-incision technique.
Hyperflex the knee and place the femoral tunnel with the transtibial guide.

Correct Answer: Prepare the femoral tunnel via an anteromedial portal or two-incision technique.

Explanation:

Question 72:

What is the most appropriate treatment at this time?

Options:

IV steroids and antibiotics
IV antibiotics
Anterior decompression and fusion
Posterior laminectomy and instrumented fusion

Correct Answer: Anterior decompression and fusion

Explanation:

DISCUSSION
Prompt diagnosis and treatment of patients with spinal epidural abscess is crucial to maintain and/or improve neurologic function. This clinical scenario stresses the importance of advanced imaging studies. It is also important to recognize the imaging features of spinal epidural abscess. T1-weighted gadolinium-enhanced images show ring enhancement with a central nonenhancing, low-signal area. In such a case, urgent decompression is indicated. Because of the location of the abscess, which is anterior to the spinal cord, an anterior decompression and reconstruction (ie, fusion) is probably the best treatment plan. Steroids are contraindicated in the presence of an epidural abscess. IV antibiotics alone will not adequately treat a patient with a neurological deficit. A posterior laminectomy and fusion will not safely allow access to the abscess.
RECOMMENDED READINGS
Bluman EM, Palumbo MA, Lucas PR. Spinal epidural abscess in adults. J Am Acad Orthop Surg. 2004 May-Jun;12(3):155-63. Review. PubMed PMID: 15161168.
View Abstract at PubMed
Ghobrial GM, Beygi S, Viereck MJ, Maulucci CM, Sharan A, Heller J, Jallo J, Prasad S, Harrop JS. Timing in the surgical evacuation of spinal epidural abscesses. Neurosurg Focus. 2014 Aug;37(2):E1. doi: 10.3171/2014.6.FOCUS14120. PubMed PMID: 25081958.
View
Abstract
at PubMed
This is the last question of the exam.

Question 73:

Options:

Weakness of hip flexion
Weakness of ankle dorsiflexion
Numbness of the medial thigh
Numbness of the lateral thigh
Numbness of the perineum

Correct Answer: Weakness of hip flexion

Explanation:

Question 74:

Options:

Syrinx of the cervical spine
Intracranial mass
Myasthenia gravis
Amyotrophic lateral sclerosis (ALS)
Fascioscapulohumeral dystrophy

Correct Answer: Amyotrophic lateral sclerosis (ALS)

Explanation:

Question 75:

A 20-year-old woman with a history of subtotal meniscectomy has a painful knee. What associated condition is a contraindication to proceeding with a meniscal allograft?

Options:

Grade I posterior cruciate ligament tear
Grade II medial collateral ligament tear
Lateral meniscal tear
5 degrees of genu varum
x 5-mm patellar chondral lesion

Correct Answer: 5 degrees of genu varum

Explanation:

Question 76:

Options:

10% decrease in amplitude, 50% decrease in latency.
10% decrease in amplitude, 50% increase in latency.
0% loss of amplitude, transient increase in latency.
50% decrease in amplitude, 10% increase in latency.
50% decrease in amplitude, 10% decrease in latency.

Correct Answer: 50% decrease in amplitude, 10% increase in latency.

Explanation:

Question 77:

Which of the following is true regarding plating of humeral shaft fractures compared to intramedullary nailing?

Options:

worse functional results
higher need for subsequent surgeries
less blood loss
higher union rates
increased postoperative shoulder stiffness

Correct Answer: worse functional results

Explanation:

Question 78:

Which of the following complications is uniquely associated with an anterior approach to the lumbosacral junction?

Options:

Nerve root injury
Erectile dysfunction
Dural tear
Pulmonary embolism
Retrograde ejaculation

Correct Answer: Retrograde ejaculation

Explanation:

Question 79:

At the time of revision knee arthroplasty, a surgeon performs a rectus snip to gain exposure to the knee. When compared with a standard parapatellar approach, what is the expected outcome?

Options:

Improvement in range of motion
Reduction in range of motion
Increase in extensor mechanism lag
No differences in motion and strength

Correct Answer: No differences in motion and strength

Explanation:

DISCUSSION:
Rectus snip during total knee arthroplasty has no effect on motion or strength at long-term follow-up. It has not been associated with extensor mechanism lag.

Question 80:

An adult patient has an 8- x 4- x 10-cm soft-tissue mass located within the adductor compartment of the thigh. Staging studies should consist of

Options:

MRI and a radiograph of the thigh and CT of the chest.
MRI of the thigh, a chest radiograph, and a CT of the pelvis.
MRI of the thigh, a total body bone scan, a chest radiograph, and a CT of the pelvis.
MRI of the thigh, a total body bone scan, a chest radiograph, and a CT of the abdomen and pelvis.
a CT of the chest and thigh, a total body bone scan, and a chest radiograph.

Correct Answer: MRI and a radiograph of the thigh and CT of the chest.

Explanation:

Question 81:

Options:

Stress fracture
Simple bone cyst
Fibrous dysplasia
Infection
Giant cell tumor

Correct Answer: Giant cell tumor

Explanation:

DISCUSSION: The radiographs reveal a lytic subchondral lesion that has a poorly defined margin and lacks mineralization. The bone scan confirms an active lesion that has central photopenia, producing the characteristic doughnut configuration. The MRI scans confirm the presence of a subchondral lesion that is modestly expansile at the lateral plateau and has low signal intensity on the T1-weighted image and a mixed high signal on the T2-weighted image. These features strongly suggest giant cell tumor of bone, more than 50% of which appear around the knee. Simple cyst is excluded by the MRI characteristics. Fibrous dysplasia is unlikely to be in a subchondral location and typically does not show this intensity of uptake on bone scan.
REFERENCES: Parsons TW: Benign bone tumors, in Fitzgerald RH, Kaufer H,
Malkani AL (eds): Orthopaedics. St Louis, MO, Mosby, 2002, pp 1027-1035.
Resnick D, Kyriakos M, Greenway GD: Tumors and tumor-like lesions of bone: Imaging and pathology of specific lesions, in Resnick D (ed): Diagnosis of Bone and Joint Disorders, ed 4. Philadelphia, PA, WB Saunders, 2002, vol 4, pp 3939-3962.

Question 82:

Options:

A 270-degree labral tear
His intention to continue contact sport activities
Anterior bony loss measuring 30% of inferior glenoid width
An inferior glenohumeral ligament avulsion (HAGL) lesion

Correct Answer: Anterior bony loss measuring 30% of inferior glenoid width

Explanation:

DISCUSSION
There is much debate in the literature regarding optimal techniques for treatment of shoulder instability. Although some studies suggest that open stabilization may result in lower recurrence rates in contact athletes, this approach is now under scrutiny. Extensive labral involvement (posterior labral involvement in this scenario) is likely more accessible via arthroscopic methods. Although HAGL lesions may be more easily accessible via an open approach (particularly for inexperienced arthroscopists), numerous authors describe successful repair via arthroscopic techniques. Among these responses, the strongest indication for an open approach, including possible bony transfer, is high-grade glenoid bone loss. Although the critical amount of bone loss is a topic of debate, most surgeons and authors suggest a cutoff of 20% to 25%.
CLINICAL SITUATION FOR QUESTIONS 90 THROUGH 92
Figure 90 is the radiograph of a 14-year-old pitcher who plays in a year-round baseball program and has vague pain in his dominant shoulder. The pain occurs with throwing, and it has been worsening for 2 months. Pain typically occurs during the late cocking phase of throwing. He has no tenderness of the rotator cuff and 5/5 rotator cuff strength. His arc of motion is symmetric between his dominant and nondominant arms. The sulcus sign is negative.

Question 83:

Reverse total shoulder arthroplasty improves kinematics in the rotator cuff deficient joint by what directional change to the center of rotation? Review Topic

Options:

Medial
Lateral
Posterior
Proximal

Correct Answer: Medial

Explanation:

Question 84:

Avascular necrosis

Options:

Slipped epiphysis
This patient has a subtle grade 1 slipped capital femoral epiphysis. He is a male Risser 0 and is overweight. He has decreased internal rotation of the involved hip in flexion. The plain pelvis radiograph shows slightly less epiphyseal height on the left side, slight posterior metaphyseal overlap, and increased irregularity of the physis. MRI confirms a lucent plane in the physis and surrounding edema. A plain film (Slide 3) confirms the diagnosis. In situ fixation was performed on this patient.

Correct Answer: Slipped epiphysis

Explanation:

Slide
A 9-year-old girl sustains an injury (Slide) as a result of a fall. What is her risk of avascular necrosis:

Question 85:

Options:

Examination would likely reveal a short neck, low posterior hairline and limited neck motion.
Serum human leukocyte antigen B27 is likely to be positive.
He is likely to be of Japanese descent.
The disease is defined by flowing ossification of the anterior longitudinal ligament at 4 consecutive levels.
Rheumatoid factor is likely to be positive.

Correct Answer: Rheumatoid factor is likely to be positive.

Explanation:

Question 86:

Options:

Medial collateral ligament rupture
Patellar dislocation
Patellar tendon rupture
Anterior cruciate ligament rupture
Posterior cruciate ligament rupture

Correct Answer: Anterior cruciate ligament rupture

Explanation:

DISCUSSION: The MRI scan shows a Segond fracture, which is a small avulsion of the lateral joint capsule from the anterolateral aspect of the proximal tibia. It is almost always associated with anterior cruciate ligament rupture and often with a tear of either the medial or lateral meniscus.
REFERENCES: Goldman AB, Pavlov H, Rubenstein D: The Segond fracture of the proximal tibia: A small avulsion that reflects major ligamentous damage. Am J Roentgenol 1988;151:1163-1167.
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 87:

Options:

Axillary
Abductor pollicis brevis
Supinator
Triceps
Biceps

Correct Answer: Biceps

Explanation:

Question 88:

Which of the following factors has been shown to increase mortality in poly-trauma patients with severe head injuries?

Options:

Delayed fixation of fractures
Decreased intracranial pressure
Intra-abdominal injury
Intra-operative hypotension
Decreased platelet count

Correct Answer: Delayed fixation of fractures

Explanation:

Question 89:

What is the preferred treatment of displaced distal clavicle fractures in children less than eight years old?

Options:

Closed reduction and pinning of the fracture
Open reduction and plating
Sling immobilization
Coracoclavicular ligament reconstruction
Open reduction and suture fixation

Correct Answer: Closed reduction and pinning of the fracture

Explanation:

Question 90:

Which of the following is a true statement regarding thoracic disk herniations? Review Topic

Options:

Are most commonly discovered during the fifth to seventh decades of life
Occur with similar frequency as cervical disk herniations
Occur most commonly in the midthoracic or apical region of the spine
Can be found in 40% of asymptomatic individuals
Are best treated surgically with posterior laminectomy and excision

Correct Answer: Can be found in 40% of asymptomatic individuals

Explanation:

Question 91:

Options:

follow-up with repeat radiographs in 6 months.
brace treatment.
posterior spinal fusion with instrumentation.
anterior and posterior spinal fusion with instrumentation.
anterior spinal fusion with instrumentation.

Correct Answer: anterior and posterior spinal fusion with instrumentation.

Explanation:

Question 92:

Options:

Arthroscopic labral debridement
Reverse periacetabular osteotomy
Resurfacing hip arthroplasty
Femoral neck osteochondroplasty and resection of the detached labrum
Femoral neck osteochondroplasty and reattachment of the labrum

Correct Answer: Femoral neck osteochondroplasty and reattachment of the labrum

Explanation:

Question 93:

Options:

recruitment in the extensor pollicis longus, abductor pollicis longus, extensor digitorum communis, and extensor carpi ulnaris muscles. Which nerve is most likely compressed?
Median
Radial
Anterior interosseous
Posterior interosseous
Lateral antebrachial cutaneous

Correct Answer: Anterior interosseous

Question 94:

Options:

Protect the airway and use smelling salts
Protect the airway, move to the shade, and place in reverse Trendelenburg
Protect the airway and protect from seizure activity
Protect the airway, start CPR, and prepare to cardiovert
Protect the airway, and move patient slowly to a spine board

Correct Answer: Protect the airway, start CPR, and prepare to cardiovert

Explanation:

Question 95:

-What is the most appropriate initial treatment?

Options:

Run a wound culture and return to the operating room for arthrotomy, irrigation, and debridement.
Return to the operating room, blister debridement, split-thickness skin grafting, and prophylactic intravenous (IV) penicillin G (PCN G) every 6 hours
Return to the operating room, blister debridement, apply topical aloe, and prophylactic IV PCN G every 6 hours
Bedside blister debridement, apply topical aloe, and prophylactic IV PCN G every 6 hours

Correct Answer: Bedside blister debridement, apply topical aloe, and prophylactic IV PCN G every 6 hours

Explanation:

DISCUSSION FOR QUESTIONS 83 AND 84
Based upon the history and description of the wound, this patient has sustained a frostbite injury to the anterior skin without evidence of infection. Frostbite, a thermal injury to local tissues, can be classified into first-, second-, third-, and fourth-degree injuries. First-degree injuries are characterized by a central whitish area surrounded by erythema. Second- and third-degree injuries are characterized by blisters that appear within the first 24 hours. Second-degree blisters are clear or cloudy, while third-degree blisters are hemorrhagic. Fourth-degree injuries are characterized by tissue necrosis. Treatment of a frostbite injury should begin as soon as it is identified, even if severity has not been determined. Treatment includes protection against mechanical irritation and keeping the injured area away from heat. The limb should be elevated and clear blisters debrided; dark blisters should be drained but not debrided. Topical treatment includes aloe application every 6 hours (silver sulfadiazine for open wounds). Nonsteroidal anti-inflammatory drugs can be given along with PCN G (500,000 U) or clindamycin (600 mg) IV every 6hours for 48 to 72 hours as prophylaxis against infection.Multiple skin incisions on the front of the knee place the skin at healing risk after surgery.
Skin oxygenation is further compromised by a lateral release, which disrupts the superior lateral geniculate artery in the peripatellar vascular anastomosis. When addressing compromised perfusion to the skin, the orthopaedic surgeon may consider not performing a lateral release, using the medial parapatellar incision,and/or not using a tourniquet during surgery. In this patient, the use of cold therapy further compromised perfusion to the skin. This patient’s wound does not reflect infection, but rather frostbite from the compromised skin perfusion and the application of cold therapy.
The physiologic responses to the effects of freezing temperatures on limbs have been categorized into 4 phases. Phase I, cooling and freezing, is characterized by vasoconstriction and vasospasm. The freezing results in mechanical destruction of cell membranes in endothelial cells in small capillaries. Phase II,rewarming, initiates as heat absorbed by the limb begins an exothermic reaction as extracellular and intracellular crystals melt. Intracellular swelling occurs and small capillaries become highly permeable,resulting in extravasation of fluid and causing edema and blisters. Phase III is characterized by progressive tissue injury resulting from inflammation, vascular stasis, and thrombosis leading to ischemia.Phase IV is recovery that can progress along 3 potential pathways: complete healing, healing with later sequelae, or early tissue necrosis leading to gangrene.
CLINICAL SITUATION FOR QUESTIONS 85 THROUGH 87
Figure 85 is the radiograph of a 13-year-old right-handed baseball player who has experienced 2 months of right-dominant shoulder pain. As a pitcher, he says he cannot “throw hard” without pain, and he develops a dull ache if he throws more than 15 pitches.

Question 96:

The CT scan reveals a nondisplaced greater trochanteric fracture. The patient is now experiencing severe pain. What is the most appropriate treatment at this time?

Options:

Liner exchange
Revision of the entire acetabular component
Revision of both the femoral and acetabular components
Partial weight-bearing activity for 4 to 6 weeks

Correct Answer: Partial weight-bearing activity for 4 to 6 weeks

Explanation:

Question 97:

Options:

an exercise program.
revision rotator cuff repair using local tissue transposition.
revision rotator cuff repair using allograft.
latissimus dorsi transfer.
combined latissimus dorsi and teres major transfer.

Correct Answer: an exercise program.

Explanation:

Question 98:

Histologically, synovial chondromatosis is characterized by

Options:

exuberant synovitis (Pannus).
loose fragments of articular cartilage embedded in the synovium.
ossified cartilage nodules embedded in the synovium.
the presence of granulomas in the synovium.
hemosiderin deposition in the synovium.

Correct Answer: ossified cartilage nodules embedded in the synovium.

Explanation:

Question 99:

Options:

Continued dressing changes
Split-thickness skin graft C. Full-thickness skin graft D. Local rotational flap

Correct Answer: Continued dressing changes

Explanation:

Question 100:

The main advantage of surgical repair of an acute Achilles tendon rupture, when compared with nonsurgical management, is reduced

Options:

stiffness of the ankle joint.
risk of deep venous thrombosis.
risk of rerupture.
cost of care.
tendon healing time.

Correct Answer: risk of rerupture.

Orthopedic Surgery Board Review MCQs: Arthroplasty, Trauma & Spine Part 255

OITE & ABOS Orthopedic MCQs: Hip, Arthroplasty & Trauma Part 242

Key Takeaway

About This Board Review Set

How to Use the Interactive Quiz

Topics Covered in Part 242

Sample Questions from This Set

Why Active MCQ Practice Works

Chapter Index