1.04 A 32-year old man sustained a closed tarsometatarsal fracture-dislocation, and a closed reduction is performed. Postreduction radiographs reveal a 3 mm offset at the first metatarsocuneiform joint. Management should not consist of:

1. A light dressing and immediate range of motion.

2. A removable brace 3. A below-knee cast.

1. In situ percutaneoeous pinning

2. ORIF

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Question 1.04 Answer 5

Tarsometatarsal joint complex fracture-dislocations may result from direct or indirect trauma. Direct injuries are usually the result of a crush and may involve associated compartment syndrome, significant soft-tissue injury, and open fracturedislocation. Indirect injuries are often the result of an axial load to the plantarflexed foot. Midfoot pain after even a minor forefoot injury should raise suspicion; up to 20% of tarsometatarsal joint complex injuries are missed on initial examination. An anteroposterior radiograph with abduction stress may reveal subtle injury, but computed tomography is the preferred imaging modality. The goal of treatment is the restoration of a pain-free, functional foot. The preferred treatment is open reduction and internal fixation, using screw fixation for the medial three rays and Kirschner wires for the fourth and fifth tarsometatarsal joints. Satisfactory outcome can be expected in approximately 90 % of patients.

Nonsurgical management of TMC injuries should be limited to those that are without fracture, nondisplaced, and stable under radiographic stress examination. As little as 2mm of displacement or the presence of a fracture within the TMC warrants fixation.

Although displaced or unstable TMC injuries have been treated by closed reduction and casting, loss of reduction was common and outcomes were variable, with a high incidence of poor results. Currently accepted surgical techniques involve either closed reduction with percutaneous Kirschner wire (K-wire) or screw fixation or open reduction with screw and/ or Kwire fixation.4-6 For fixation of the medial threeTMTjoints, screw fixation may be preferable to K-wires because ligamentous healing may require as much as 12 to 16 weeks of immobilization to occur, and K-wires can become loose, necessitating removal as early as 6 weeks. Regardless of the technique used, the goal should be anatomic reduction of the affected joints because numerous studies have documented that clinical outcome correlates with accuracy of reduction. J Am Acad Orthop Surg 2003;11:260-267

2.04 The results of TKA after closed lateral wedge tibial osteotomy are most often complicated by:

1. Extensor lag secondary to patella alta.

2. An increased need for medial soft-tissue releases.

3. Lateral femoral condyle hypoplasia

4. Decreased flexion secondary to patella baja.

5. Osseous insufficiency of the medial tibial plateau.

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Question 2.04 Answer 4

High tibial osteotomy is most commonly used for unloading of

unicompartmental osteoarthritis. Most report 80% satisfactory results 5 years and 60% at 10 years after osteotomy. 1965 Coventry descrifed a closing wedge osteotomy to correct varus deformity. The major complication is recurrence of deformity, which is decreased if not overcorrecteded to at least 8 degreees of valgus and the patient is not substantially overweight. Favorable results are predicted with age less than 60, purely unicompartmental, ligamentous stability and preop arc of at least 90 degrees.

Scuderi, Windsor and Insall reported 89% developed significant patella baja which they postulated might be caused by shortening of the patellar tendon after prolonged immobilization, new bone formation at the osteotomy in the area of the insertion of the patellar tendon, and fibrosis of the patellar tendon. It does not affect the success of the procedure or prohibit future TKA, but does make future TKA more difficult. Campbell's page 929-930

3.04 The biphasic nature of normal articular cartilage results in:

1. Stress shielding of the solid matrix.

2. Time-dependent behavior when subjected to constant load.

3. Time-dependent behavior when subjected to constant deformation.

4. Constant strain and stress that will rise and then plateau.

5. Support of load primarily by the stress developed in the solid matrix.

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Question 3.04 Answer 1

Biphasic Theory - normal collagen is composed of a solid (collagen) and liquid (water). Either one is incompressible. Compression with loading is achieved by movement of water around the collagen, therefore the "solid matrix" is stress shielded by the liquid one. Although cartilage has a constant porosity, under sudden loads there isn't enough time for the fluid to dissipate and the solid structure is shielded by the fliuid one. Correctly answering this question requires understanding the biphasic theory.

"Recognizing that fluid flow and deformation are interdependent has led to the modeling of cartilage as a mixture of fluid and solid components [59-61]. This is referred to as the biphasic model of cartilage. In this modeling, all of the solidlike components of the cartilage, proteoglycans, collagen, cells, and lipids are lumped together to constitute the solid phase of the mixture. The interstitial fluid that is free to move through the matrix constitutes the fluid phase. Typically, the solid phase is modeled as an incompressible elastic material, and the fluid phase is modeled as incompressible and inviscid, that is, it has no viscosity [60]. Under impact loads, cartilage behaves as a single-phase, incompressible, elastic solid; there simply isn't time for the fluid to flow relative to the solid matrix under rapidly applied loads. For some applications, a viscoelastic model is used to describe the behavior of cartilage in creep, stress relaxation, or oscillating shear. Although the mathematics of modeling cartilage is outside the scope of this chapter, some examples illustrate the fundamental fluid- solid interaction in cartilage."

CLINICAL RELEVANCE: VARIABLE PERMEABILITY

Deformation-dependent permeability may be a valuable mechanism for maintaining load sharing between the solid and fluid phases of cartilage. If the fluid flowed easily out of the tissue, then the solid matrix would bear the full contact stress, and under this increased stress, it might be more prone to failure.

http://connection.lww.com/products/oatis/documents/smch5.pdf

4.04 Which of the following findings is associated with the use of a standard adult backboard in young children with suspected spinal injury?

1. Decreased spinal blood flow

2. Decreased thoracic kyphosis

3. Increased cervical flexion

4. Difficulty in performing a thorough physical examination

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5. Restriction of abdominal musculature needed for respiration

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Question 4.04

J Am Acad Orthop Surg 1998;6:204-214

Answer 4

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5.04 Which of the following factors is the strongest predictor of clinical outcomes after decompression for lumbar spinal stenosis?

1. A distinct herniated intervertebral disk

2. Comorbd conditions

3. Facet hypertrophy as the cause of canal compromise

4. Gender

5. Associated spondylolithesis

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Question 5.04 Answer 2

Previous reviews have suggested that surgical treatment of lumbar stenosis is successful (defined as significant pain relief with a return to activities of daily living) in 80% to 85% of cases. However, other authors have found a much lower rate of successful results, perhaps attributable to differing definitions of a "successful result." In a retrospective review 4 years after lumbar decompression, Katz et al found "successful outcomes" (defined as relief of pain and no reoperation) in only 57% of cases. Factors associated with unsuccessful outcomes were multiple comorbidities, single-level decompressions, and a 5% annual incidence of degeneration at levels adjacent to the

decompression. In another shorter-term follow-up study of patients who underwent surgery for lumbar stenosis, the authors identified predominating low back pain as another factor associated with poor outcomes after surgical treatment of lumbar stenosis. J Am

Acad Orthop Surg 1999;7:239-249

6.04 ITEM DELETED A 72-year-old woman who was playing golf

inadvertently struck the ground during a drive and noted the sudden onset of pain and was unable to elevate her arm. Examination the following day revealed a lump in the area of her biceps muscle. Initial management consisted of a period of rest and anti-inflammatory drugs. Four weeks after the injury, she continues to have pain and weakness in elevation. What is the best course of action?

1. EMG of the axillary nerve

2. U/S of the long heard of the biceps

3. MRI

4. Physical therapy 5. Arthroscopic labral repair

back answer Question 04.6 DELETED

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7.04 What is the standard treatment for low-grade intramedullary osteogenic scarcoma?

1. Surgery only

2. Surgery and chemotherapy

3. Surgery and radiation therapy

4. Chemotherapy only

5. Radiation therapy only

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Question 7.04 Answer 1

Low-grade central osteosarcoma is a rare variant of osteosarcoma that often is mistaken for fibrous dysplasia. 1.2-1.9% of all cases of osteosarcoma. Approximately 25-55% of these tumors invade the surrounding adjacent soft tissue. If the tumor is not adequately resected early in its course, pulmonary metastasis may develop as a late complication. Low-grade intrameduallary osteosarcoma is microscopically similar to that of parosteal osteosrcoma, it is usually located in the metaphyseal bone about the knee joint in adults, (distal femur, 41%). Radiographically it created a sclerotic density in metaphyseal bone. Carries an excellent prognosis and is treated with local surgery alone. Medical therapy: The use of radiation therapy or chemotherapy in the treatment of low-grade central osteosarcoma is controversial because neither has been proven

beneficial. Surgical therapy: Wide excision, which may include amputation, is the treatment of choice because the recurrence rate after curettage or marginal excision is 80-100%. Of the tumors that recur, 15% are high-grade lesions.

Recurrence after wide local excision or amputation is negligible.

8.04 Which of the following factors is most likely to correlate with the formation of severe heterotopic ossification follwing knee dislocation?

1. Delay of more than 3 weeks in ligament reconstruction surgery

2. Open medial collateral reconstruction

3. Bicruciate reconstruction

4. Injury severity score

5. Reconstruction of more than two ligaments

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Question 8.04 Answer 4

OBJECTIVE: To determine the relationship of multiple variables, including the Injury Severity Score (ISS), closed head injury (CHI), and timing and type of surgery to formation of motion-limiting heterotopic ossification (HO) following knee dislocation. DESIGN: Longitudinal

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observational study. SETTING: University level 1 trauma center. PATIENTS/PARTICIPANTS: Thirty-five consecutive patients with 36 knee dislocations (OTA fracture and dislocation classification 40-D) admitted over a 26-month period. MAIN OUTCOME

MEASUREMENTS: Admission ISS, Glasgow Coma scale (GCS) scores, CHI, timing (> or < 3 weeks from injury) and type (open or arthroscopic) of surgery, number of cruciate ligaments reconstructed, medial surgical procedure, and eventual presence or absence of motion-limiting HO. RESULTS: A classification system for HO was developed ranging from none (type 0) to ankylosing (type IV) HO. Twenty-nine patients with type 0-III HO recovered an average range of motion of 126 degrees at an average of 14 months (group A). Six patients formed ankylosing type IV HO (group B). The ISS in group A ranged from 9 to 26. ISS in group B ranged from 26 to 50 (P < 0.001). Regarding the formation of type IV HO, the sensitivity of an ISS >/=26 was 100%, the specificity was 97%, and the positive predictive value was 86%.

Patients in group B had a greater incidence of documented CHI (P < 0.025). Timing and type of surgery, number of ligaments reconstructed, and whether or not the patient had a medial surgical procedure had no statistical influence on degree of HO formation. CONCLUSIONS: An ISS of 26 seems to be a discrete boundary above which patients with knee dislocation are at extremely high risk for type IV HO formation if undergoing surgical reconstruction and below which patients are likely spared this complication. The presence of a CHI is a significant factor in type IV HO formation, although harder to quantify. None of the remaining independent variables studied were significantly related to ankylosing type IV HO formation. J Orthop Trauma. 2003 May;17(5):338-45

9.04 What is the most common cause of failed reconstructions of the anterior cruciate ligament?

1. Technical error

2. Failure of graft incorporation

3. Patient selection

4. Significant reinjury

5. Premature return to sport

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Question 9.04

Answer = 1

Technical shortcomings are the most common cause of failure in patients who come to revision ACL reconstruction. In one series, technical failures, such as nonanatomic tunnel placement, inadequate notchplasty, improper graft tensioning, inadequate graft fixation, or insufficient graft material, were implicated in 77% of the revision cases.

Tunnel location dictates thesometry of the graft over a range of motion, and poorly placed tunnels can lead to increased graft tension. It has been estimated that 70% to 80% of technical failures are due to malpositioned tunnels. The ACL graft can withstand only a small amount of strain before deforming. Malpositioned grafts incur excessive tension and may be impinged or become lax, leading to failure. The most common error is improper positioning of the femoral tunnel. A femoral tunnel placed too far anterior and tensioned in extension will lead to excessive strain during flexion (Fig. 1). This results in overconstraint of the knee with loss of flexion or stretching of the graft. If the same anteriorly placed graft is tensioned in flexion,

the joint will not be constrained, but there will be unacceptable laxity in extension and failure. J Am Acad Orthop Surg 1999;7:189-198

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10.04 A partial laceration of the flexor tendon should be repaired when the percentage of tendon lacerated is more than

1. 10 %

2. 20 3.

40 4.

60

5. 80

back answer Question 10.04

Answer = 4

There has been debate regarding the appropriate management of partial tendon lacerations. Initial investigations created considerable controversy because they recommended that partial flexor tendon lacerations should not be repaired. Recent studies have demonstrated that partial lacerations of 60% or less need not be sutured, but that those greater than 60% should be repaired. The possibility of entrapment, rupture, and triggering of unrepaired partial tendon lacerations has also been reported. J Am Acad Orthop

Surg 1995;3:44-54

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11.04 Which of the following laboratory studies is predictive of wound healing prior to performing a lower extremity amputation?

1. Total protein level

2. Calcium level

3. Serum albumin level

4. Platelet count

5. ESR

back answer Question 11.04

Answer = 3

A serum albumin level of below 3.5 g/dl indicates malnourished patient. An absolute lymphocyte count below 1500/mm3 is a sign of immune deficiency. If possible, amputation surgery should be delayed in such patients. An absolute Doppler pressure of 70 mm Hg is the minimum inflow level. The ischemic index is the ratio of the Doppler pressure at the level being tested to the brachial systolic pressure. Genreally accepted to require an ischemic index of 0.5 or greater. Transcutaneous partial pressure of oxygen (TcpO2) is the present gold standard of vascular inflow. TcpO2 values of 40 mm Hg correlate with acceptable wound healing

(eliminates false positive predictions with using area under the Doppler waveform). Pressures less than 20 mm Hg are predictive of poor healing. Miller 505-6

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12.04 A 7-year-old boy who sustained a supracondylar humerus fracture has a gunstock deformity following removal of the cast. Surgical correction of the angular deformity with primarily result in improved

1. cosmesis of the arm

2. Range of motion of the elbow

3. pain relief in the elbow

4. functional outcome

5. rate of growth in the arm 12.04- 1 Cosmesis of the arm

Gunstock deformity or Cubitus varus is the most common complication following supracondylar humerus frx, originally, etiology of cubitus varus was thought to occur because of growth disturbance of distal humeral epiphysis; -this may be true but is uncommon; - current thinking is that it stems from malreduction of fx, with medial displacement, internal rotation, and extension of the distal fragment; - this then permits distal fragment to tilt into varus; - cubitus varus produces a cosmetic deformity but little function deficit; - during reduction, a small amount of medial or lateral displacement or small amount of anterior or posterior angulation may be tolerated, but any malrotation is not acceptable;

Baumann's Angle= humeral capitellar angle: angle between long axis of humeral shaft & growth plate of lateral condyle, will reliably predict final carrying angle after reduction; - normal is about 85-89 deg, but it is best to judge the carrying angle as compared to the uninjured side; - a deviation more than 5 deg compared to the opposite side should not be accepted; - increases in Bauman's angle will occur w/ residual varus and internal rotation deformities; Reference essentially said that lateral closing wedge osteotomy for correction of posttraumatic cubitus varus yielded good correction of deformity w/ minimal complications.

13.04 A 26-year-old man has activity-related swelling of the thigh and aching pain. He reports that symptoms improve with rest. Examination reveals a soft thigh mass. Axial T1 and T2 weighted MRI scans are shown in figures 1a and

1b. What is the most likely diagnosis?

1. Desmoid tumor

2. Hemangioma

3. Synovial Cyst

4. Sarcoma

5. Malignant fibrous histiocytoma 2- Hemangioma

Clinical Presentation: firm mass, may demonstrate reddish or blue color depending on tumor depth; mass may vary in size and may become larger (and more painful) w/ physical activity, or w/ standing but may reduce in size (and become less tender) once the patient is flat on the examining table; size will not reduce with simple elevation; look for associated dilated adjacent veins; some patients may demonstrate intermittent bleeding and ulceration

Cavernous hemangiomas: invasive tumors which often manifest as a deep soft tissue mass, often involving the thigh; intramuscular hemangiomas may become engorged with blood during activity sometimes causing pain, and in contrast, w/ rest the swelling and pain abate; may contain calcifications or phleboliths (seen on x-ray); check for palpable thrill or audible bruit; - superficial skin changes are often not present; despite their vascular origin, hemangiomas do not metastasize or undergo malignant transformation

Most are treated w/ non-operative management- compression stockings, embolization, local or systemic steroids sometimes helpful

Reference is a retrospective review of patients w/angiodysplastic lesions of the extremities which showed subcutaneous hemangiomas irritated sensory nerves, intramuscular lesions mimicked compartment syndromes, intraarticular lesions caused recurrent hemarthroses, and periarticular or large lesions resulted in hypertrophy or limb length discrepancy.

14.04 Which of the following actions diminishes intracapsular hip pressure following a transcervical femoral neck fracture?

1. Forcibly extending the hip to correct the major deformity

2. Forcibly internally rotating the hip to improve the retroversion

3. Placement of a distal femoral traction pin and initiation of balanced suspension

4. Applying 15lb traction to the affected extremity

5. Allowing the leg to assume a flexed, abducted, and externally rotated position

   14.04 5- Allowing the hip leg to assume a flexed, abducted, and externally rotated position

   Reference is a prospective clinical study where the intraarticular pressure of 55 patients with intracapsular femoral neck fractures was measured intraoperatively with the hip in different positions. Intraarticular hemarthrosis was quantified by a preoperative sonography examination. In 75% of the patients, increased intraarticular pressure caused by the hemarthrosis was found. The spontaneous median pressure increased significantly from 22 mm Hg with extension (28 mm Hg) and internal rotation of the hip joint (56 mm Hg). The lowest pressure was found in 70 degrees flexion (15 mm Hg). The median pressures increased within the first 24 hours after injury from 26 mm Hg in the first 6 hours to 46 mm Hg from 7 to 24 hours. Even in the first and second weeks after trauma, increased median pressures were detected (8.5 mm Hg and 13 mm Hg, respectively). No significant difference was found between undisplaced and displaced fracture types. Because increased joint pressure in other studies correlates with reduced perfusion of the femoral head, it can be deduced that reduction maneuvers without capsulotomy can compromise the circulation of the femoral head. Capsulotomy and osteosynthesis of the femoral neck at the earliest time possible is the best prophylaxis of tamponade. If the osteosynthesis is delayed, a preoperative sonography after admission and a control sonogram after 6 hours is recommended. In the event of relevant hemarthrosis, immediate therapeutic drainage is suggested for patients who will receive joint conserving osteosynthesis.

   Bonnaire F, Schaefer DJ, Kuner EH, Hemarthrosis and hip joint pressure in femoral neck fractures. Clin Orthop. 1998 Aug;(353):148-55

   15.04 Which of the following factors minimizes patellar maltracking in total knee arthroplasty?

   1. Increased posterior tibial slope

   2. Medialization of the patellar component

   3. Internal rotation of the femoral component

   4. Internal rotation of the tibial component

   5. Joint line elevation

15.04 2- Medialization of the patellar component Patellar complications of total knee arthroplasty remain the most common cause of

pain and reoperation. Laboratory studies have suggested that medialization of the patella will improve tracking of the patella on the trochlea of the femoral component. Reference: This study examined factors that influence patellar tracking after total knee arthroplasty. A total of 62 knees were evaluated radiographically for postoperative patellar tracking. Six factors were examined regarding their influence on postoperative patellar tracking. This study showed the effects of patellar component position, patellar resection angle, and lateral retinacular release on postoperative patellar tracking. There was no significant effect of the remaining 3 factors: the thickness of the patellar resection, preoperative patellar tilt, and rotational alignment of the femoral component. A medialized patellar component and obliquity of resection of the patella are effective for obtaining proper patellar tracking.

16.04 Pedical screw instrumentation to supplement posterolateral fusion after decompression for spinal stenosis can decrease the rate of which the following postoperative complications?

1. Pulmonary Embolus

2. Neurologic Injury

3. Pseudoarthrosis

4. Bleeding

5. Pain

   16.04 3- Pseudoarthrosis

   Reference was a randomized prospective clinical study of seventy-six patients who had symptomatic spinal stenosis associated with degenerative lumbar spondylolisthesis. All patients underwent posterior decompression with concomitant posterolateral intertransverse process arthrodesis. The patients were randomized to a segmental transpedicular instrumented or noninstrumented group. RESULTS: Sixtyseven patients were available for a 2-year follow-up. Successful arthrodesis occurred in 82% of the instrumented cases versus 45% of the noninstrumented cases.

   17.04 Figures 2a and 2b show the radiographs or a 4-year-old child who has a limp. Based on these findings, management should consist of

   1. irrigation and debridement

   2. subtalar arthrodesis

   3. a short leg walking cast

   4. a long leg non-weightbearing cast

5- core decompression of

17.04 3- a short leg walking cast

the tarsal bones

Kohler's disease is a self limiting avasulcar necrosis of the navicular; usually unilateral and affects children, most often boys; onset is at age 4 in boys and age 5 in girls; navicular is subjected to repetitive compressive forces during wt bearing which may be a risk factor for AVN; navicular is last bone in foot to ossify & delayed ossification appears to make the navicular more vulnerable to compressive damage; compressive forces can occlude the vessels of the soft ossification center rendering it avascular

Clinical Manifestations: -painful limp, shifting weight to lateral edge of foot to relieve pressure on longitudinal arch; pain tenderness, and swelling develop in the region of the navicular; contraction of tibialis posterior muscle may be painful

Radiologic Findings: navicular shows patchy areas of sclerosis and rarefication w/ loss of normal trabecular pattern; navicular may appear collapsed or in some cases will have normal shape with a uniform increase in density and minimal fragmentation; it is occassionally seen on opposite, asymptomatic foot

Treatment: symptomatic treatment is needed for the pain and swelling; soft longitundinal arch supporters, medial heel wedge, and limitation of strenuous activity; **if pain is severe or persists, a short leg walking cast may be used for 4 to 6 weeks**, followed by use of shoe modifications

Prognosis: - disease is self limiting & prognosis is excellent; navicular typically regains its normal shape before foot completes growth, and normal ossification is usually completed in two years

Symptomatic or true Kohler's disease must be differentiated clinically from asymptomatic radiographic changes resembling Kohler's osteochondrosis. The patients showed a significant decrease in morbidity with the use of a short-leg cast for an eight-week period. Whereas patients who were not treated in a short-leg cast had symptoms for an average duration of 15 months, treated patients had symptoms for less than three months.

18.04 When harvesting the flexor digitorum longus distally in the foot, which of the following tendons crosses immediately below it?

1. Flexor hallucis longus

2. Flexor hallucis brevis

3. Adductor hallucis

4. Abductor hallucis

5. Quadratus Plantae

   18.04 1- Flexor hallucis longus

   FDL and FHL pass through the second plantar muscle layer of the foot. At the ankle the FDL is more anterior (closer to the medial malleolus) than the FHL, however as they pass into the foot the FHL crosses deep to the FDL. So the FHL is closer to the 1st MT. The FHL is deep to ("below") the FDL and caution must be taken not to damage this structure when harvesting the FDL in the foot.

   19.04 A patient who underwent anterior cruciate ligament reconstruction with a central one third bone-patellar-bone autograft 1 week ago now reports swelling of the right knee. Examination reveals that the patient is afebrile, has a large knee effusion, has limited range of motion, and cannot perform a straight leg raise. Radiographs show only routine postoperative changes. What is the next most appropriate step in management?

   1. Electrodiagnostic testing

   2. KT-2000 testing

   3. Compression dressing

   4. MRI

   5. Knee aspiration

19.04 5- Knee aspiration

In cases of suspected septic arthritis after ACL reconstruction, laboratory studies and aspiration followed by culture testing should be performed liberally to avoid the otherwise frequently delayed diagnosis.

Matava MJ, Evans TA, Wright RW, Shively RA, Septic arthritis of the knee following anterior cruciate ligament reconstruction: results of a survey of sports medicine fellowship directors.

Arthroscopy. 1998 Oct;14(7):717-25

The results of this survey confirm the widely held belief that septic arthritis of the knee is a relatively rare complication following ACL reconstruction. Once an infection is encountered, culture-specific IV antibiotics and surgical joint irrigation with graft retention are recommended as initial treatment. Graft excision and hardware removal is considered only for those infections resistant to initial treatment and for the infected allograft.

20.04 Chondrocyte modulation is derived primarily from

1. neural pathways

2. cellular immune response

3. immunoglobulin activity

4. cell-to-cell contact

5. mechanotransduction

   20.04 5- Mechanotransduction

   Mechanical and electrochemical environments such as stress, strain, osmotic pressures and electrical potential have been reported to modulate the biosynthetic activities of chondrocytes within articular cartilage. Chondrocytes in articular cartilage respond to mechanical modulation by altering their biosynthetic activities, consistent with the type and duration of the mechanical input. This response may be an attempt by the cells to remodel their extracellular matrix so that it can meet the mechanical demands exerted upon it.

   The mechanical environment of the chondrocytes in articular cartilage is complex, and various physico-electrochemical signals are generated when articular cartilage is subjected to mechanical loads. Compressive loading of articular cartilage results initially in pressurization of the interstitial fluid, followed by the movement of fluid from regions of high to low fluid pressurization. As the pressure dissipates, greater amounts of the applied loads are borne by the solid matrix and chondrocytes. The movement of fluid and dissolved ions relative to fixed charges in the tissue generates streaming potentials and streaming currents that may also act as regulators of chondrocyte activities.

   Various in vitromechanical-loading models have shown that mechanical loads modulate chondrocyte biosynthetic activities in a dose- and frequency-dependent manner. Static loading of articular cartilage explants at stresses that exceed 0.2MPa is generally inhibitory to chondrocyte biosynthetic activities. However, at stresses 0.2MPa, gene expression and synthesis of cartilage ECM components may be stimulated, depending on the mode of loading. Cyclic or dynamic loading has been observed to stimulate the synthesis of cartilage ECM components. Even chondrocytes grown in hydrogels retain their abilities to respond to mechanical loading in a frequency- and dose-dependent manner. Despite these findings, the mechanisms through which chondrocytes perceive and transduce extracellular mechano-electrochemical signals are not well understood.

   21.04 A 35-year-old woman who has had chronic pain in her palm after falling 6 months ago now notes persistent paresthesias in her ring and small fingers. Current radiographs are shown in Figures 3a and 3b. Based on these findings, treatment should consist of

   1. arthrodesis of the fourth and fifth carpometacarpal joints

   2. lunotriquetral arthrodesis

   3. excision of the pisiform

   4. excision of the hook of the hamate

   5. neuroplasty of the ulnar nerve in Guyon's canal

21.04 4- Excision of the hook of the hamate

Hook of the Hamate Fracture- The most common symptom is pain in the palm that is aggravated by grasp. Weakness of grasp and dorsal wrist pain are also common. Ulnar nerve paresthesia or weakness and mild carpal tunnel syndrome are frequently present. Pain is accentuated w/ axial loading of ring and little finger metacarpals; dx is usually confirmed by point tenderness over hook 1 cm distal and radial to the pisiform; almost all patients complain of pain and tenderness on ulnar side of palm or on the dorsoulnar aspect of the wrist. Tenderness directly over the hamulus is always present, and grip strength typically is diminished.

Tenosynovitis, tendon fraying, or tendon rupture may be demonstrated in 25% of the cases and is not related to the use of steroids. In all cited studies excision produced generally excellent results, particularly in patients with an athletic injury or with no associated additional injury. A nonathletic injury or the presence of associated trauma adversely affected results.

Origin of the flexor digiti minimi brevis and opponens digiti minimi may cause a failure of a hamate fracture to heal; -nonathletic injury or crush injury adversely affects outcome

Immediate immobilization of acute fractures may result in fracture healing and obviate operative intervention. Open reduction and internal fixation is feasible but offers little advantage over excision.

*** Treat Hook of Hamate Fractures with excision***

22 . ITEM DELETED

• 23.04 A patient wishes to return to driving after undergoing surgery for a displaced fibular fracture of the right ankle. A return to normal braking time can be expected how many weeks after surgery?

1. Immediately

2. 2 weeks

3. 6 weeks

4. 9 weeks

5. 16 weeks

   23.04 A pt wishes to return to driving after undergoing surgery for a displaced fibular fracture of the right ankle. A return to nml braking

   time can be expected how many weeks after surgery?

   • IV - 9 wks

   • Answer is based on the following article:

   • Lower-Extremity Function for Driving an Automobile After Operative Treatment of Ankle Fracture. Kenneth A. Egol, MD et al JBJS 2003

   • A computerized driving simulator was developed andtested. Eleven healthy volunteers were tested once to establishnormal mean values (Group I), and a group of thirty-one volunteerswith a fracture of the right ankle were tested at six, nine,and twelve weeks following operative repair (Group II). Thesubjects were tested with a series of driving scenarios (city,suburban, and highway). Scores on the Short Form MusculoskeletalAssessment were recorded at six, nine, and twelve weeks andwere compared with the results of the driving test. The effect of the time of the visit and of the testing conditionon the braking times was investigated.

   • Conclusion: By nine weeks, the total braking time of patientswho have undergone fixation of a displaced right ankle fracturereturns to the normal, baseline value

   • 24.04 A 35-year-old man who is a known IV drug abuser has had increasing pain and swelling around his sternum for the past few weeks. Examination reveals painful swelling around the left sternoclavicular joint. Radiographs are normal. Laboratory studies show normal CBC and WBC counts, and the erythrocyte sedimentation rate is only minimally elevated. What is the most likely diagnosis?

     1. Osteolysis of the medial clavicle

     2. Idiopathic hyperostosis of the medial clavicle

     3. Transient anterior instability of the sternoclavicular joint

     4. Osteoarthritis of the sternoclavicular joint

     5. Septic arthritis of the sternoclavicular joint

24. A 35 yo man who is a known IV drug abuser has increasing pain and swelling around his sternum for the past few weeks.

Examination reveals painful swelling around left sternoclaviular joint. Radiograghs

are normal. Lab studies show normal CBC, WBC counts, and the ESR is only minimally elevated. What is the likely Diagnosis?

• V- Septic arthritis of the Sternoclavicular jt.

• IV drug abuser is the biggest tip off. Isolated SC jt pain is another tip off. He is on the young side of OA. The other choices should have associated radiographic changes also.

• See following table:

• 25.04 A 68 year old woman who underwent unicompartmental knee arthroplasty 2 years ago now reports progressively worsening

  pain during weightbearing activities. Radiographs are shown in Figures 4a and 4b. The cause of the failure is primarily related to

  1. patellofemoral arthritis

  2. ultra-high molecular weight polyethylene wear.

  3. a thin ultra-high molecular weight polyethylene insert.

  4. poor cement technique.

  5. mechanical properties of the bone.

  25.04 A 68 yo woman who underwent unicompartmental knee arthroplasty 2 years ago now reports progresssively worsening pain

  during wt. Bearing activities. Radiographs are shown in 4a, 4b. The cause of the failure is primarily related to

• V- Mechanical properties of the bone

• Weale et al.JBJS br 2000.

• The Author concludes that failure of unicompartmental knee replacement are caused by progressive osteoarthritis of the knee and/or failure of the prosthesis. Changes in alignment, eg. Knee falling into varus, was an important factor in failure of these prostheses. At five years most fell into varus. This was due to either poly wear or subsidence.

• In our case the knee is in obvious varus. While the space between the components is maintained, there is significant subsidence of the tibial component.

• 26. 04 The primary functional deficit in Sprengel's deformity is limitation of what shoulder motion?

  1. Internal rotation

  2. Abduction

  3. Adduction

  4. Flexion

  5. Extension

  26.04 The primary functional deficit in sprengel's deformity is limitation of what shoulder motion?

• II. Abduction

• Sprengel's deformity: Undescended scapula. Most common congenital anomaly of the shoulder in kids. Scapula is small, wide, and medially rotated.Limited scapulothoracic movement, especially abduction. 50% have fibrous band or bony bar from superior angle to posterior elements of C4-7.

• Common association with many congenital disorders particularly Klippel-feil

• 27. 04 Intramedullary nailing of proximal metaphyseal tibial fractures most commonly results in what type of deformity at the fracture site?

I- Varus and Flexion

1. Varus and extension

2. Valgus arid Flexion

3. Valgus and extension

4. Valgus and internal rotation

   27.04 Intramedullary nailing of proximal metaphyseal tibia fx most commonly result in what type of deformity at the fracture site?

   • III. Valgus and flexion

   • Fractures of the proximal third of the tibial shaft do not appear to respond as favorably to intramedullary nailing as do fractures in the distal 2/3 of the tibia. Valgus, apex anterior angulation, and residual displacement at the fracture site are common after nailing. Surgical errors of a medialized nail entry point and a posteriorly and laterally directed nail insertion angle contributed to malalignment.

   • Proximal third tibial fractures require a neutral to lateral entrance angle to ensure a more anatomic reduction and centromedullary nail orientation to offset the tendency for valgus angulation.

1. 04 Which of the following is considered the host common cause of recurrent ankle sprains in dancers?

   1. Poor proprioception

   2. Hypermobility of the subtalar joint

   3. Lateral ligament laxity

   4. Peroneal tendon weakness

   5. Posterior tibial tendon dysfunction

      28.04 Which of the following is considered the most common cause of recurrent ankle sprains in dancers?

      • IV- Peroneal tendon weakness

      • Ankle sprains are the most common acute skeletal injury in dancers. Typically inversion type injuries, they affect the lateral ligamentt complex along with the Anterior Tib-Fib Lig., and lateral talocalcaneal ligaments.

      • The peroneal tendons suppsedly help to control subluxation/motion at the ankle joint, especially with ruptures to the ATFL. Weak peroneals have been shown to cause varus subluxation of the ankle.

      • Lateral ligamnet laxity apparently causes rotational instability rather than varus instability.

2. 04 61-year-old man has had neck pain after slipping and falling in the bathtub 2 days ago. He is neurologically intact. The lateral radiograph shown in Figure 5 reveals no obvious fractures. What is the next most appropriate step in management?

   I- Flexion and extension radiographs

   1. Lumbar radiographs

   2. Myelography

   3. CT

   4. Gallium scan

   29.04 A 61 yo man has neck pain after slipping and falling in bathtub 2 days ago. He is neurologically intact. The lateral radiogragh

   shown in fig 5 reveals no obvious fractures. What is the next appropriate step in management?

   • IV- CT

   • Xray reveals a "bamboo spine" = ankylosing spondylitis.

   • The incidence of spine fx in AS pts is 4x that of the general population.

   • Furthermore, occult Fx of the spine are often missed on xray b/c:

     • Distorted anatomy

     • Increased density of ossified ligs

     • Poorly outlined disc spaces

     • Hx of previous minor trauma

     • Multiple noncontigous fx

   • Interestingly the author recommends MRI over CT but that is not one of the choices

30.04 A 49-year-old woman with knee pain undergoes arthroscopic excision of an isolated nodular area. AP and lateral radiographs reveal no osseous or soft-tissue abnormalities. An axial Ti-weighted MRI scan and low- and high-power photomicrographs are shown in Figures 6a through 6c. Management should now consist of

1 - observation.

1. irradiation.

2. wider excision of the involved synovium, followed by irradiation

3. wide resection of the knee joint and prosthetic reconstruction

4. above-knee amputation

   30.04 49 yo woman with knee pain undergoes arthroscopic excision of an isolated nodular area. AP and Lat Xrays reveal no osseous

   or

   soft tissue abnormalities. An Axial T1 weighted MRI scan and low and high powered photomicrographs are shown in 6A-6C. Management should now consist of

   • I.- observation

   • PVNS usually presents as a monoarticular arthritis that affects the knee in 80% of cases, followed in frequency by the hip, ankle, and calcaneocuboid joints. Patients typically complain of pain, locking, and recurrent swelling.

   • tumor cells in both lesions are polyhedral, moderately sized, and resemble synoviocytes.

   • Microscopic examination reveals masses of polygonal or round cells with pink cytoplasm and round nuclei Included among the invading synovial cells are multinucleated giant cells hemosiderin-laden macrophages, and fibroblasts . Hemosiderin can also be seen between cells, in synovial lining cells, and in polygonal cells. Foci of hemorrhage are common

   • Treatment for the localized form is marginal excision and for the diffuse form, total synovectomy. Radiotherapy in the diffuse lesion may be justified if surgery fails to control the process.

31. 04 What nerve runs in Hunter's canal?

1. Nerve to the rectus femoris

2. Cutaneous branch of the obturator nerve

3. Articular branch of the peroneal nerve

4. Saphenous

5. Posterior femoral cutaneous

31.04 What nerve runs in Hunter's canal?

• VI. Saphenous

• Hunter's canal, better known as the Adductor canal starts at at the apex of the femoral triangle where the sartorius and Adductor longus cross. The canal is formed in a space beween the vastus medialis and adductors. Its roof is the sartorius.

• Its contents include saphenous nerve, nv to the v. medialis as well as the femoral artery/vein.

• 32. 04 When compared with static exercise, dynamic exercise has an advantage in that it improves an athlete's cardiac output by increasing the 1- heart rate.

1. V02 max.

2. sympathetic tone.

3. stroke volume.

4. blood pressure.

   32.04 When compared with static exercise, dynamic exercise has an advantage in that it improves an athlete's cardiac output by

   increasing the

   • IV- stroke volume

   • Cardiac Output = Stroke volume X heart rate.

   • If you know the above formula you can eliminate most of the other choices.

   • Apparently HR does not increase significantly in athletes who perform dynamic (endurance) excercises. In fact they tend toward bradycardia.

33.04 Failure to splint the hand in an intrinsic-plus posture following a crush injury often leads to flexion contractures of the proximal interphalageal joints because of

1. increased fluid capacity of the PIP joints in flexion

2. intrinsic muscle contractures

3. intrinsic muscle atrophy

4. extrinsic imbalance from MCP joint extension

5. the loss of the normal CAM effect of the MCP joint

   33.04 Failure to splint the hand in an intrinsic plus posture following a crush injury often leads to

   flexion contractures of the PIP jts because of

   • IV. Extrinsic imbalance from MCP Jt extension

   • "Intrinsic minus" or "negative hand position" is a functionally disadvantageous position consisting of: MCP extension, IP flexion, thumb adduction, wrist flexion. It is the natural position that the hand assumes after injury.

   • The MCP joint is the key to the development of the "negative hand". The MCP joint capsule and collaterals have maximum laxity and consequently, greater fluid capacity when in extension. The initial response to any insult to the hand is swelling/ edema. After an injury, edema fluid fills the joints, hydraulically pushing the MCP into extension. This position increases flexor tension and decreases extensor tension. Consequently, the PIP/DIP jts are forced into flexion. Unlike the MCP, the PIP/DIP jts have the same fluid capacity in flexion/extension. The positions of the PIP/DIP therefore, are secondary to MCP position.

   • Long term immobilization in the Intrinsic minus position leads to joint contracture.

34.04

What is the most common complication associated with treatment of a closed midshaft tibial fracture with a reamed locked intramedullary nail?

1. Delayed union

2. Infection

3. Knee Pain

4. Interlocking screw breakage 5- Compartment syndrome

back answer Question 34.04 Answer 3

This question only asks you to compare the complication rates after operative treatment of tibial shaft fractures with an IM nail so nonoperative treatment does not have to be considered here. Note, though, that a similar question has appeared in the past asking to identify knee pain as a significantly increased incidence in IM nail vs non-operative treatment.

Knee pain is the most common complication associated with IM nailing of the tibia. OKU 7 cites an incidence from 10-60% and 2 studies quoted in Rockwood and Green offer numbers of 57% and 56.2% respectively. Patellar-splitting approaches yield higher incidences of knee pain than paratendon approaches. The exact cause of the knee pain remains unclear. Knee pain after IM nail is more common in young active patients.

Delayed union is not quoted as being a common complication of IM nailing. When comparing the time to union in Rockwood and Green's Tables 46-11, 46-12 (non-op cast treatment) to 46-18 (IM nailing of closed fractures) the numbers are comparable. Several studies on IM nailing of closed tibia fractures have infection rates from 05.2% (not a common complication). Screw breakage depends on the size of the nail and screws. Because nonreamed nails are often smaller they also have smaller screws and therefore the incidence of screw breakage has been higher in non-reamed nails vs. reamed nails. Most series have an incidence of 10-20% breakage (reamed 02.9%). Dr. Riemer has a published study showing that screw breakage is less common with titanium screws vs.

stainless (2.9% vs 25%). There is no clear clinical evidence that IM nailing of tibial fractures causes or increases the risk of compartment syndrome. There is some evidence that excessive traction during IM nailing may cause it.

Reference(s)

Koval KJ (ed): Orthopaedic Knowledge Update 7. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 479-488. Keating JF, Orfaly R, O'Brien PJ: Knee pain after tibial nailing. J Orthop Trauma 1997; 11:10-13

Toivanen JA, Vaisto O, Kannus P, Latvala K, Honkonen SE, Jarvinen MJ: Anterior knee pain after intramedullary nailing of fractures of the tibial shaft: A prospective, randomized study comparing two different nail-insertion techniques. J Bone Joint Surg AM 2002; 84:580-585.

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35.04

The Ponseti method of clubfoot treatment involves which of the following concepts?

1. Short leg casts for 6 to 8 weeks, followed by percutaneous heel cord tenotomy

2. Comprehensive posterior, medial, and lateral subtalar release preformed at age 3 months

3. Supination of the foot during initial cast correction

4. Abduction of the foot with counterpressure at the calcaneocuboid joint

5. Correction of equinus prior to correction of supination back answer Question 35.04 Answer 3

Congenital clubfoot (or Talipes equinovarus) deformities include equinus of the hindfoot, varus below the subtalar joint, cavus (plantarflexion of the forefoot on the hindfoot) and adduction of the foot. The Ponseti method developed by Dr. Ignacio V. Ponseti at the University of Iowa corrects all of the deformities of clubfoot simultaneously except for equinus, which is corrected in the final cast.

This technique uses serial long-leg casting (one per week for about 6-8 weeks) to stretch the ligaments of the tarsal bones thereby reversing the deformities. An achilles tenotomy is most often needed to correct equinus in the final step. There are no other operative releases done in this technique. To correct the adduction, the entire foot is serially put into more abduction. Dr. Ponseti makes it clear that counterpressure at the calcaneocuboid joint alone does not abduct the entire foot and actually puts a harmful external rotation force on the ankle mortise. Therefore, in the Ponseti method, the foot is abducted at the Lisfranc line, the navicular cuneiform joints, the Chopart line and the subtalar joint simultaneously and a counterpressure is placed on the lateral talar head to prevent external rotation.

Reference(s)

Ponseti IV: The Ponseti technique for correction of congenital clubfoot. J Bone Joint Surg Am 2002; 84:1889-1890.

Herzenberg JE, Radler C, Bor N: Ponseti versus traditional methods of casting for idiopathic clubfoot. J Pediatr Orthop 2002; 22:517-521.

Cummings RJ, Davidson RS, Armstrong PF, Lehman WB: Congenital clubfoot. Instr Course Lect 2002; 51:385-400.

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36.04

A 79-year-old man with a long-standing rotator cuff tear reports that the steroid injections he has been receiving no longer provide pain relief. A radiograph is shown in Figure 7. Treatment should now consist of

1. primary rotator cuff repair.

2. rotator cuff repair with an orthobiologic patch.

3. latissimus dorsi transfer.

4. shoulder arthrodesis.

5. humeral head arthroplasty.

back answer

Question 36.04 Answer 5

This question asks for appropriate surgical management of the presented condition. The clinical case is fairly classic for rotator cuff arthropathy- a seventy-some year old male (though usually occurs in females) with a long-standing massive RTC tear who is now failing conservative management. The provided radiograph confirms the diagnosis with superior migration of the humeral head due to the RTC tear, "acetabularization" of the acromio-gleno-humeral axis, subchondral sclerosis and cyst formation and osteophytes.

The cited references make the case for hemiarthroplasty for the treatment of rotator cuff arthropathy. Answers "1" and "2" are clearly wrong because by definition this condition has an irreparable RTC tear. Latissimus dorsi transfer was not mentioned at all in the cited articles. It has been used in cases of irreparable RTC tears to provide external rotation and head depressing forces. I speculate that this is a newer, less reliable treatment, is felt by the test writer to be as such or is used in less advanced disease (not in a patient like this with such obvious bony changes). Shoulder arthrodesis is not as good an option in this question for this patient to regain function especially since this patient has none of the common indications for this procedure (neuropathies, paralysis, failed arthroplasty, tumor resection, etc.)

Reference(s)

Collins DN, Harryman DT II: Arthroplasty for arthritis and rotator cuff deficiency. Orthop Clin North Am 1997; 28:225-239.

Zuckerman JD, Scott AJ, Gallagher MA: Hemiarthroplasty for cuff tear arthropathy. J Shoulder Elbow Surg 2000; 9:169-172.

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37.04

A 14-year-old boy who is a cross-country runner reports a 6-week history of medial knee pain that has prevented him from training.

Radiographs are normal. An MRI scan is shown in Figure 8. Management should consist of

1. a knee brace.

2. home physical therapy followed by a return to running.

3. protected weight bearing for 4 to 6 weeks.

4. intramedullary rodding of the tibia.

5. referral to an orthopaedic oncologist. back answer

Question 37.04 Answer 3

Given this clinical history and MRI scan, this young runner has a tibial stress fracture. The onset of symptoms is relatively acute, the patient has the most common mechanism namely high-impact exercise and the pain is located to both the area indicated on the MRI scan and the area most typical for a stress fracture of the tibia (the posterior medial cortex or compression side). Also, the plain films are negative as they often are with stress fractures. The fact that the plain films are normal also helps in ruling out a neoplastic process because one would expect some plain film changes for the apparent size of the "lesion" on MRI.

Per the grading system table and algorithm (included below) from the cited JAAOS article the treatment for this condition and the correct answer for this question is protected weight bearing for 4-6 weeks. Use of a knee brace is not discussed at all for treatment of tibial stress fractures. Physical therapy is also not the treatment especially if combined with a return to running - cessation of activity is what's needed. IM nailing of the tibia is a treatment for tibial stress fracture but usually only done after a solid non-operative trial is attempted (the cited study reported good results in 5 patients with "recalcitrant" fractures). We have already said we have a low suspicion for neoplasm so referral is unnecessary.

Reference(s)

Boden BP, Osbahr DC: High-risk stress fractures: Evaluation and treatment. J Am Acad Orthop Surg 2000; 8:344-353.

Ohta-Fukushima M, Mutoh Y, Takasugi S, Iwata H, Ishii S: Characteristics of stress fractures in young athletes under 20 years. J Sports Med Phys Fitness 2002; 42:198-206.

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38.04

Figure 9 shows the AP radiograph of a 56-year-old man who has had increasing wrist pain for the past 6 months. He denies any specific trauma to the wrist. What is the most likely diagnosis?

1. Osteonecrosis of the scaphoid

2. Gout

3. Rheumatoid arthritis

4. Scapholunate ligament disruption 5- Radial styloid malunion

   back answer

   Question 38.04 Answer 4

   This is just recognition of the signs of degenerative arthritis of the wrist - specifically the pattern of scapholunate advanced collapse (SLAC) which is the most common form of wrist arthritis. The cited articles detail the sequence of this pattern of arthritis. Progressive degenerative changes begin first between the scaphoid and the radial styloid (narrowing, sclerosis) which results in a sharpening of the normal curve of the styloid (seen in the radiograph). The degeneration progresses next along the remainder of the radioscaphoid articulation (also obvious on this radiograph). The third step in the sequence involves degenerative changes at the lunate/capitate joint (maybe beginning here). The radiolunate articulation remains unaffected in this condition (this is also noted in the picture). Therefore, scapholunate ligament disruption is the answer to this question. This disruption is what begins this process and a reconstruction of this integrity (of one kind or another) is what helps this condition. You probably either already know many or all of the radiographic findings for the other conditions listed or else these are easy to look up so I'll leave it at that.

   Reference(s)

   Watson HK, Ballet FL: The SLAC wrist: Scapholunate advanced collapse pattern of degenerative arthritis. J Hand Surg Am 1984; 9:358-365.

   Manske PR (ed): Hand Surgery Update. Rosemont, IL, American Academy of Orthopaedic Surgeons, 1994, p 96.

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   39.04

   An 11-year-old child has left knee pain. A radiograph, MRI scan, bone scan, and biopsy specimen are shown in Figures 10a through 10d. Which of the following has been shown to improve survival in this disease?

   1. Radiation therapy

   2. Chemotherapy

   3. Gene therapy

   4. Amputation

   5. Limb-sparing surgery back answer

Question 39.04 Answer 2

This patient has osteosarcoma. The patient's age, clinical history and the provided radiographs all point to this diagnosis. The histology slide confirms the diagnosis (osteoid production). Apparently, there are no metastases as evidenced by the bone scan.

Once the diagnosis is made, the question asks to consider which of the choices

improves survival. One of the reference sources is OKU 7 and the section of osteosarcoma sort of goes through

the history of treating this disease. It says "since the advent of multiagent chemotherapy, patient survival has improved dramatically". The most common agents used for osteosarcoma are high dose methotrexate, adriamycin and cis-platinum. Answers 4 and 5 (amputation and limb-sparing surgery respectively) are attractive answers and are also discussed extensively in the reference articles. Both are used currently in the treatment of this cancer but are used in conjunction with chemotherapy. Amputation used to be the gold-standard treatment before chemo and is still used for refractory disease. Although limb-sparing surgery is almost always attempted in conjunction with chemo in non-metastatic disease, it has not been shown to increase survival (over amputation alone). It also has better functional outcome but a higher rate of reoperation and no measurable quality of life benefit. Radiation therapy (answer 1) is not discussed as a treatment for osteosarcoma. Gene therapy (answer 3) is also not discussed but is possibly a future therapy.

Reference(s)

Koval KJ (ed): Orthopaedic Knowledge Update 7. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 155-181.

Rougraff BT, Simon MA, Kneisl JS, Greenberg DB, Mankin HJ: Limb salvage compared with amputation for osteosarcoma of the distal end of the femur: A long-term oncological, functional, and quality-of-life study. J Bone Joint Surg Am 1994; 76:649-656.

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40.04

A 24-year-old baseball pitcher who has had shoulder pain for the past 6 months undergoes glenohumeral arthroscopy. The anatomic finding shown in Figure 11 reveals a

1. Bankart lesion.

2. superior labral tear.

3. rotator cuff tear.

4. normal anatomic variant.

5. detached middle glenohumeral ligament

back answer

Question 40.04 4

The key to this question is the simply having the knowledge that there are recognized anatomic variants in the anterosuperior aspect of the glenoid labrum (this knowledge won't guarantee that you answer the question right but will keep option "4" open for consideration). The cited references discuss the described anatomic variants at the anterosuperior aspect of the glenoid labrum but do not discuss how one specifically identifies such a variant (I guess that just comes with experience; both having been shown them and having seen and identified them yourself). Three variants are mostly described: 1. sub-labral foramen 2. sub-labral foramen with cord-like middle glenohumeral ligament (MGHL) 3. absence of glenohumeral labral tissue at the anterosuperior glenoid with a cord-like MGHL. I don't know exactly which variant is shown here, but I am guessing it is the first (just a foremen) because I don't think the MGHL looks cord-like. As I said the articles don't explain how to identify this as a variant and I don't know that anyone could correctly and consistently identify variants versus the other choices based only on one still shot. So, I guess this is just test taking skills - knowing that these variants exist and assuming that it's the answer they want because why would they ask you to identify one of the other choices based on one intra-op photo (no x-rays, MRI, etc.).

Reference(s)

Rao AG, Kim TK, Chronopoulos E, McFarland EG: Anatomical variants in the anterosuperior aspect of the glenoid labrum: A statistical analysis of seventy-three cases. J Bone Joint Surg Am 2003; 85:653-659.

Steinbeck J, Liljanqvist U, Jerosch J: The anatomy of the glenohumeral ligamentous complex and its contributions to anterior shoulder stability. J Shoulder Elbow Surg 1998; 7:122-126.

41.04

When comparing the results of the surgical versus nonsurgical treatment of the thoracolumbar burst fracture in a neurologically intact patient without posterior ligament disruption, surgical treatment yields

1. superior radiographic results but a higher complication rate.

   Answer

2. superior radiographic results but equivalent clinical outcome scores.

3. superior clinical outcome scores and a lower complication rate.

4. equivalent clinical outcome scores.

5. a lower complication rate but equivalent clinical outcome scores. back answer

   Question 41.04 4

   The first cited article is from 1993 out of Spinethat basically showed that nonoperative treatment of thoracolumbar burst fractures without posterior instability and without neurological compromise is a perfectly acceptable treatment. The results show that deformity progression is only slight and that the canal remodels. The second citation from JBJS 2003 is a prospective, randomized study comparing operative vs. nonoperative treatment. Average kyphosis, average canal compromise improvement, average pain scores and return to work were all similar between the 2 groups. Patients with nonoperative treatment reported less disability. SF-36 and back pain questionnaires were similar but favored nonoperative treatment. Operative treatment had more complications. Based on these studies answer 4 is correct.

   Reference(s)

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   Wood K, Butterman G, Mehbod A, Garvey T, Jhanjee R, Sechriest V: Operative compared with nonoperative treatment of a thoracolumbar burst fracture without neurological deficit: A prospective, randomized study. J Bone Joint Surg Am 2003; 85:773-781.

   Mumford J, Weinstein JN, Spratt KF, Goel VK: Thracolumbar burst fractures: The clinical efficacy and outcome of nonoperative management. Spine 1993; 18:955-970.

   42.04

   A 6-year-old boy sustains multiple injures in a high-speed motor vehicle accident. In addition to his fractures, he has intra-abdominal injuries for which a splenectomy is required. To prevent subsequent sepsis from encapsulated organisms, long-term management will require

   1. daily antibiotic prophylaxis.

   2. splenic hormone replacement.

   3. Escherichia coli vaccine.

   4. bone marrow transplantation. 5- splenic transplantation.

      back answer

      Question 42.04 1

      I wouldn't want to be responsible for this care but if you want to treat these patients be my guest. Here are the recommendations from one of the cited articles:

      1. All splenectomised patients and those with functional hyposplenism should receive pneumococcal immunization and patients not previously immunized should receive Haemophilus Influenza type b vaccine. Patients not previously immunized should receive

         Answer

         Meningococcal Group C conjugate vaccine. Influenza immunisation should be given. Life long prophylactic antibiotics are still recommended ( oral Phenoxymethylpenicillin or Erythromycin ).

      2. Patients developing infection, despite measures, must be given systemic antibiotics and admitted urgently to the hospital.

      3. Patients should be given written information and carry a card to alert health professionals to the risk of overwhelming infection. Patients may wish to invest in an alert bracelet or pendant.

      4. Patients should be educated as to the potential risks of overseas travel, particularly with regards malaria and unusual infections, for example those resulting from animal bites.

      5. Patient records should be clearly labelled to indicate the underlying risk of infection. Vaccination and revaccination status should be clearly and adequately documented.

      Reference(s)

      Sponseller PD (ed): Orthopaedic Knowledge Update: Pediatrics 2. Rosemont, IL, American Academy of Orthopaedic Surgeons, 2002, pp 73-79.

      Davies JM, Barnes R, Milligan D: Update of guidelines for the prevention and treatment of infection in patients with an absent or dysfunctional spleen. Clin Med 2002; 2:440-443.

      Gandhi RR, Keller MS, Schwab CW, Stafford PW: Pediatric splenic injury: Pathway to play? J Pediatr Surg 1999; 34:55-58.

      43.04

      What is the most common reason for a poor outcome following a crush injury to the foot?

      1. Persistent neuritis

      2. Posttraumatic arthrosis

      3. Poor wound healing

         back to this question next question

      4. Clawtoe deformity 5- Infection

back answer

Question 43.04 1

Crush injuries to the foot are bad injuries. In the cited article less than half of the patients had a good functional outcome. The patients that did the best were the ones who strictly adhered to the treatment protocol (no surprise). But, even some of these had poor outcomes. Poor results usually resulted after delayed treatment, delayed soft tissue coverage, development of neuritis or RSD, or those involved in workers' comp/litigation (no surprise again). Recommended treatment includes prompt recognition and treatment of compartment syndrome, early soft tissue coverage and rigid skeletal stabilization.

Reference(s)

Myerson M, McGarvey WC: Crush injuries and compartment syndromes, in Myerson M (ed): Current Therapy in Foot and Ankle Surgery. St Louis, MO, Mosby-Year Book, 1993, pp 264-273.

Answer

Myerson MS, McGarvey WC, Henderson MR, Hakim J: Morbidity after crush injuries to the foot. J Orthop Trauma 1994; 8:343-349.

44.04

A patient sustained a Hawkins type II talar neck fracture and underwent open reduction and internal fixation. The patient now has residual decreased subtalar motion without pain and stands on the lateral border of the foot. What is the most likely cause of these findings?

1. Stiffness secondary to immobilization during treatment

2. Talar collapse secondary to osteonecrosis

3. Valgus malunion

4. Varus malunion

5. Nonunion

back answer

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Question 44.04 Answer 4

Talar neck fractures are serious injuries and poor results are disappointingly common. One fairly common complication is malunion (either varus or dorsal). Canale noted malunions in up to 27% of fractures and Lorentzen in up to 28%. Varus malunions change the mechanics of the foot and are difficult to treat. It results in the foot having a cavus attitude and causes the patient to walk on the lateral boarder of the foot. Decreased motion and pain may result because of the changes in biomechanics or in combination with arthritis of the joint. Though the patient in this question does not have pain, varus malunion can result in a painful callus on the lateral aspect of the foot as well as early fatigue. If combined with arthritis there can be even more pain. Stiffness due to immobilization (answer 1) is a concern but the key to this question is the "stands on the lateral boarder of the foot". Early ROM is advocated by some to avoid stiffness due to immobilization. Talar collapse would almost certainly be associated with pain. Valgus malunion is not described in these articles. Nonunion is possible but is not as common as delayed union or malunion and would also be associated with pain.

Reference(s)

Saunders R: Fractures and fracture-dislocations of the talus, in Coughlin MJ, Mann RA (eds): Surgery of the Foot and Ankle, ed 7. St Louis, MO, Mosby, 1999, pp 1465-1518.

Daniels TR, Smith JW: Talar neck fractures. Foot Ankle 1993; 14:225-234.

04.45. Wear of metal-on-metal articulations in total hip arthroplasty is characterized by which if the following findings?

1. Fewer number of particles/wear volume compared with ceramic/ceramic bearings

2. Increased incidence of cancer secondary to higher serum metal levels

3. Rapidly declining levels of serum metal levels following hip arthroplasty

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4. Ionically charged wear particles

5. Lower in vitro wear rates compared with ceramic/ceramic bearings

   • Answer 04.45 # 4

   • Poor reference for this question. You can arrive at the answer by strict process of elimination. A few things first. Keep in mind that ceramic/ceramic bearings have the lowest wear rates and thus produce fewer number of particles (1 and 5 out). Serum metal levels in metal-on-metal arthroplasties increase following surgery, as corrosion takes place (3 out). In the mid 90's there was a concern for malignancy in patients with metal-on-metal arthroplaties; however, studies have found gross variation in the incidence of cancer in patients with such arthroplasties, and no statistical significant difference. There is still no consensus concerning the long-term effects of metal-onmetal articulations (2 out).This leaves 4 as an attractive answer. We know that metals are subject to corrosion, which is a chemical reaction process that weakens the metal. All metals corrode; the severity of corrosion is determined by the chemical composition of the metal. There are three types of corrosion affecting implant materials: galvanic, crevice, and fatigue. Galvanic corrosion occurs when an electrical current is established between two metals that have different chemical compositions. To avoid catastrophic galvanic corrosion, stainless steel should never be used with either cobalt or titanium alloys. Crevice corrosion occurs when the fluid in contact with the metal becomes stagnant, which then becomes acidic secondary to oxygen depletion. Finally fatigue corrosion may occur if the passive oxide film on the implant surface has been scratched or cracked. Once fatigue corrosion begins, the implant weakens and may fail below the endurance limit of the material.

     Orthopaedic Knowledge Update: Hip & Knee Reconstruction 2. Rosemont, IL, Americal Academy of Orthopaedic Surgeons, 2000, pp 25-34. Jazrawi L, Kummer FJ, Di Cesare PE: Alternative Bearing Surfaces for Total Joint Arthroplasty. J Am Acad Orthop Surg 1998;6:198-203

     1. Which of the following findings is a predisposing factor for an acute lateral patellar dislocation?

        1. Hypoplastic medial femoral condyle

        2. Dysplastic vastus lateralis

        3. Patella baja

        4. Decreased Q angle

        5. Excessive internal rotation of the femur

   • Answer 04.46 # 5

   • Most acute patellar dislocations occur during the second decade. Lateral dislocations are by far the most common direction of injury. Patients with abnormal patellofemoral mechanics sustain patellar dislocations with less trauma and soft tissue injury compared with normal subjects. Predisposing factors for dislocation include hypoplastic lateral femoral condyle, dysplastic vastus medialus obliqus (VMO), patella alta, contracted iliotibial band, tight lateral retinaculum, valgus knee deformity, increased Q angle, ligamentous laxity, lateral insertion of patellar tendon on tibia, excess internal rotation of the femur / external rotation of tibia, previous patellar dislocations and injury to medial patellofemoral ligament (MPFL). Some authors favor open exploration of the MPFL following arthroscopic examination for acute patella dislocations.

Braham S, Vrahas MS, Fu FH: Knee fractures in the athlete. Orthop Clin North Am 2002;33:566-574

1. Which of the following substances is labeled with technetium Tc 99m in a conventional bone scan?

   1. calcium

   2. phosphate

   3. Alkaline phosphatase

   4. Biphosphonate

   5. Type I collagen

   Item deleted 04.47

2. What is the preferred type of graft for skin loss of the palmar aspect of the hand?

   1. Unmeshed split-thickness

   2. Meshed split-thickness

   3. Multiple pinch

   4. Full-thickness

   5. Full-thickness with attached subcutaneous fat

      • Answer 04.48 # 4

      • In general, soft tissue coverage in the hand should supply tissue that is thin, pliable, durable, and that allows for tendon gliding. The goal is to replace "like with like". Ideally, the reconstruction should allow for sensation, dynamic function, and restoration of form. Skin grafts are usually autografts and they are either splitthickness skin grafts (STSG) or full-thickness skin grafts (FTSG). Compared to STSG, full thickness grafts contract less, are more durable and flexible, and have better sensation. They are the preferred grafts for areas prone to shear and load such as fingertips, the palm, and areas over joints. STSG are better for dorsal hand wounds. STSG can be meshed or unmeshed. Meshed STSG have fewer problems with seromas, hematomas, and infections; therefore, they have better take. However, the appearance of unmeshed STSG is more aesthetically satisfying.

   Hand Surgery Update 3: Hand, Elbow, & Shoulder. Rosemont, IL, American Society for Surgery of the Hand, 2003, pp470-492.

3. What ligament is attached to the displaced distal tibial articular fracture shown in Figures12a and 12b?

   1. Anterior talofibular

   2. Anterior tibiofibular

   3. Posterior talofibular

   4. Posterior tibiofibular

   5. Calcaneofibular

      • Answer 04.49 # 4

      • Ankle (AP & lateral) x-rays show a non-displaced lateral malleolus fracture and a minimally displaced posterior malleolar fracture. Mortise is well preserved. No tibiotalar dislocation/subluxation. Medial malleolus seems intact. The injury to the posterior plafond component or

   posterior malleolus is a posterolateral avulsion fracture resulting from the pull of the posterior-inferior tibiofibular ligament. If this fragment constitutes >25-30% of the plafond surface, and/or is displaced more than 2 mm, the fragment needs internal fixation. The origin of the posterior tibiofibular ligament is broad, covering most of the horizontal distal surface of the tibia. As the ligament fibers sweep laterally and distally to insert on the fibula they fit over the trochlea.

   Orthopaedic Knowledge Update: Trauma 2. Rosemont, IL, Americal Academy of Orthopaedic Surgeons, 2000, pp 203-225

   Michelson JD: Ankle fractures resulting from rotational injuries. J Am Acad Orthop Surg 2003;11:403-412

4. A 35-year-old man with ankylosing spondylitis has progressive sagittal plane imbalance, difficulty with horizontal gaze, and thigh fatigue with standing. Radiographs are shown in Figures 13a and 13b. Maximum correction of the sagittal decompensation can be accomplished at a single level by which of the following procedures?

1. Smith-Peterson osteotomy (posterior closing wedge hinging on the posterior longitudinal ligament)

2. Transpedicular wedge resection osteotomy

3. Combined anterior and posterior surgery

4. Anterior opening wedge osteotomy

5. Vertebral column resection

• Answer 04.50 # 2

• In the radiographs we have AP / lateral spinal xrays of a patient with known ankylosing spondylitis. Of note, there are bilateral total hip arthroplasties. There is marked thoracic kyphosis, and mild thoracolumbar scoliosis. No evidence of acute fx/ dislocations. Notice that the question specifically states… maximum correction of the sagittal decompensationcan be accomplished at a single levelby which of the following procedures? Surgical correction of the kyphosis deformity with osteotomy was first done in 1945. Since then, surgeons have tried several different approaches and techniques to correct the stiff kyphosis. The transpedicular wedge osteotomy was described by Thomasen (1985) for the correction of deformity secondary to ankylosing spondylitis. In this technique the spinous process of L2 and the upper part of L3 are removed; the laminae of the second and the upper part of the third lumbar vertebrae are also removed as well as the articular processes of L2-3 and the pedicles of L2. A wedge fracture is created on the posterior wall of the vertebral body of L2. Then, plates are fixed to the spinous processes of T12-L1 and L3-4. Thomasen osteotomy places the apex of correction anteriorly, serving to shorten the spine and avoid anterior column lengthening. Advantages include the prevention of neural compression by creation of a large, shared neural foramen through removal of the pedicles, limited stretch of anterior structures, and cancellous bone healing. This technique provides maximum correction of the deformity, and can be accomplished at a single level. You either know it, or you don’t.

 

Berven SH, Deriven V, Smith JA, Emami A, Hu SS, Bradford DS: Management of fixed sagittal plane deformity: Results of the transpedicular wedge osteotomy. Spine 2001;26:2036-2043.

Thomasen E: Vertebral osteotomy for correction of kyphosis in ankylosing spondylitis.

Clin Orthop 1985;194:142-152