Menu

3. Adult Reconstruction (Hip & Knee) MCQs

Practice Set 317 of 326

This practice set contains high-yield board review questions covering key concepts in 3. Adult Reconstruction (Hip & Knee). Each clinical scenario is designed to test your diagnostic and management skills relevant to this subspecialty.

Question 6321

Topic: 3. Adult Reconstruction (Hip & Knee)

A 15-year-old boy with Hemophilia B presents with recurrent hemarthroses of the right knee despite adequate factor prophylaxis. Radiographs show early joint space narrowing without significant subchondral collapse. Which of the following is the most appropriate next step?

. Total knee arthroplasty
. Arthroscopic synovectomy
. Open synovectomy
. Radiosynovectomy
. Arthrodesis

Correct Answer & Explanation

. Radiosynovectomy

Explanation

Radiosynovectomy (using isotopes like Phosphorus-32 or Yttrium-90) is highly effective for decreasing the frequency of hemarthroses in patients with refractory hemophilic synovitis but minimal cartilaginous damage.

Question 6322

Topic: 3. Adult Reconstruction (Hip & Knee)

A 28-year-old man with Hemophilia B requires a total knee arthroplasty for end-stage hemophilic arthropathy. To safely perform this surgery, what is the target factor IX activity level for the perioperative period (surgery day to post-op day 3)?

. 10-20%
. 30-40%
. 60-80%
. 80-100%
. > 150%

Correct Answer & Explanation

. 80-100%

Explanation

For major orthopedic surgeries like TKA in hemophilia patients, factor levels should be corrected to 80-100% immediately preoperatively. It should be maintained near that level for the first 3-5 postoperative days to prevent catastrophic bleeding.

Question 6323

Topic: 3. Adult Reconstruction (Hip & Knee)

A 35-year-old man with severe Hemophilia A presents with a slowly enlarging, painless mass in his right thigh over the past two years. Imaging reveals an encapsulated cystic mass with intramural calcification eroding into the femur. What is the most likely diagnosis?

. Soft tissue sarcoma
. Hemophilic pseudotumor
. Chronic osteomyelitis
. Myositis ossificans
. Echinococcal cyst

Correct Answer & Explanation

. Hemophilic pseudotumor

Explanation

Hemophilic pseudotumors are encapsulated hematomas that progressively expand due to recurrent bleeding. They can cause pressure necrosis, erode adjacent bone, and become massive, requiring complex multidisciplinary surgical management.

Question 6324

Topic: 3. Adult Reconstruction (Hip & Knee)

A 13-year-old obese boy presents with left knee pain and a limp. Examination of the left hip reveals obligatory external rotation when the hip is passively flexed. Radiographs of the pelvis show a 'slip' of the proximal femoral epiphysis. What is the most appropriate definitive treatment?

. Spica cast immobilization
. Closed reduction and internal fixation
. In situ single screw fixation
. Proximal femoral osteotomy
. Total hip arthroplasty

Correct Answer & Explanation

. In situ single screw fixation

Explanation

Correct Answer: In situ single screw fixationSlipped Capital Femoral Epiphysis (SCFE) is best treated with in situ fixation to prevent further slippage and promote physeal closure. This is typically achieved using a single cannulated screw placed in the center of the epiphysis. Closed reduction is contraindicated as it increases the risk of avascular necrosis.

Question 6325

Topic: 3. Adult Reconstruction (Hip & Knee)

A 6-year-old male child presents with a progressive valgus deformity of his right knee and a palpable mass. Reviewing the classic imaging of Dysplasia Epiphysealis Hemimelica

, what is the most appropriate primary surgical principle if a mechanical block and significant deformity are present?

. En bloc wide resection with 2 cm margins.
. Intra-articular excision of the overgrowth while preserving the native epiphysis and joint surface.
. Arthroscopic joint debridement and synovectomy only.
. Immediate total joint arthroplasty.
. Observation until skeletal maturity followed by corrective osteotomy.

Correct Answer & Explanation

. Intra-articular excision of the overgrowth while preserving the native epiphysis and joint surface.

Explanation

Surgical management of symptomatic DEH involves careful excision of the bony overgrowth to relieve mechanical blocks and correct deformity. It is critical to meticulously preserve the normal native epiphyseal cartilage to prevent early secondary osteoarthritis.

Question 6326

Topic: 3. Adult Reconstruction (Hip & Knee)

A 7-year-old girl presents with proximal muscle weakness, a heliotrope rash over her eyelids, and firm, painful subcutaneous nodules over her extensor surfaces. Radiographs reveal extensive soft tissue calcifications.

Which of the following orthopedic complications is most likely to necessitate surgical intervention in this specific patient?

. Progressive idiopathic-like scoliosis
. Calcinosis cutis causing joint contractures
. Avascular necrosis of the femoral head
. Atlantoaxial instability
. Pathologic fractures from cystic bone lesions

Correct Answer & Explanation

. Calcinosis cutis causing joint contractures

Explanation

The patient has juvenile dermatomyositis with calcinosis cutis, a common and morbid complication. These painful subcutaneous calcifications can ulcerate, become infected, or cause severe joint contractures that may require surgical excision to restore range of motion.

Question 6327

Topic: Total Hip Arthroplasty (THA)

A 35-year-old female presents with a trimalleolar ankle fracture. Preoperative CT scan reveals a large, displaced posterior malleolus fragment involving 35% of the articular surface, necessitating direct visualization and posterior-to-anterior screw fixation with a buttress plate. To optimally facilitate this specific surgical approach, which of the following patient positions is most appropriate?

. Supine with a bump under the ipsilateral hip
. Supine with the leg externally rotated
. Prone or lateral decubitus
. Lithotomy position
. Supine with the knee flexed to 90 degrees over a radiolucent triangle

Correct Answer & Explanation

. Prone or lateral decubitus

Explanation

Correct Answer: CWhen a posterior malleolus fracture requires direct visualization and fixation (e.g., due to a large fragment size, articular comminution, or the need for buttress plating), a direct posterior or posterolateral approach is indicated. The text notes that if a significant posterior malleolus fracture requires a direct posterior approach, the patient may need to be positioned prone or in the lateral decubitus position. The supine position with a bump is standard for lateral and medial malleolus access but does not provide adequate exposure for a direct posterior approach.

Question 6328

Topic: 3. Adult Reconstruction (Hip & Knee)

A 62-year-old male with severe post-traumatic ankle osteoarthritis is being evaluated for a total ankle arthroplasty (TAA). Which of the following conditions is considered an absolute contraindication to performing a TAA in this patient?

. Body mass index (BMI) of 32 kg/m2
. Concomitant subtalar osteoarthritis
. Avascular necrosis involving greater than 50% of the talar body
. A history of a remote tibial shaft fracture treated with an intramedullary nail
. Age younger than 65 years

Correct Answer & Explanation

. Avascular necrosis involving greater than 50% of the talar body

Explanation

Avascular necrosis of more than 50% of the talar body is an absolute contraindication to total ankle arthroplasty because it leads to early component subsidence and catastrophic failure. Other absolute contraindications include active infection, Charcot neuroarthropathy, and severe peripheral vascular disease.

Question 6329

Topic: 3. Adult Reconstruction (Hip & Knee)

A 7-year-old boy with spastic quadriplegic cerebral palsy presents with worsening right hip pain. Radiographs reveal a Reimer's migration percentage of 55% on the right and 15% on the left. The right hip has broken the Shenton line. What is the most appropriate surgical intervention?

. Adductor and psoas tenotomies only
. Botulinum toxin injections to the adductors
. Varus derotational osteotomy (VDRO) of the proximal femur with a pelvic osteotomy
. Total hip arthroplasty
. Girdlestone resection arthroplasty

Correct Answer & Explanation

. Varus derotational osteotomy (VDRO) of the proximal femur with a pelvic osteotomy

Explanation

In children with cerebral palsy, a migration percentage >50% generally indicates a progressive subluxation or dislocation that requires comprehensive bony reconstruction. This typically involves a femoral VDRO combined with a pelvic (Dega or San Diego) osteotomy to stabilize the hip.

Question 6330

Topic: 3. Adult Reconstruction (Hip & Knee)

A 6-year-old boy with spastic quadriplegic cerebral palsy presents for evaluation. Pelvic radiographs demonstrate a left hip migration percentage of 50%, with breaking of the Shenton line. Which surgical intervention is most appropriate to provide a durable hip reconstruction?

. Bilateral adductor and iliopsoas tenotomies alone
. Proximal femoral varus derotational osteotomy (VDRO) with pelvic osteotomy
. Total hip arthroplasty
. Girdlestone resection arthroplasty
. Chiari shelf osteotomy alone

Correct Answer & Explanation

. Proximal femoral varus derotational osteotomy (VDRO) with pelvic osteotomy

Explanation

In children with cerebral palsy and a hip migration percentage >40%, soft-tissue releases alone are inadequate. Comprehensive bony reconstruction with a proximal femoral VDRO and a concomitant pelvic osteotomy is the gold standard.

Question 6331

Topic: 3. Adult Reconstruction (Hip & Knee)
A 32-year-old man presents with chronic dorsal wrist pain and decreased grip strength. Radiographs demonstrate sclerosis and fragmentation of the lunate. This condition is most classically associated with which of the following anatomic variants?
. Ulnar positive variance
. Ulnar negative variance
. Madelung deformity
. Scapholunate coalition
. Triquetral hypoplasia

Correct Answer & Explanation

. Ulnar negative variance

Explanation

The patient has Kienbรถck's disease (avascular necrosis of the lunate). This condition is classically associated with ulnar negative variance, which is thought to increase the shear and compressive forces transmitted across the radiolunate joint, predisposing the lunate to microtrauma and subsequent avascular necrosis.

Question 6332

Topic: 3. Adult Reconstruction (Hip & Knee)

A 35-year-old active man undergoes a total hip arthroplasty (THA). The surgeon selects a ceramic-on-ceramic bearing surface to minimize wear. Which of the following is a unique clinical complication specifically associated with this bearing surface?

. Accelerated osteolysis from submicron particulate debris
. Audible squeaking during range of motion
. Trunnionosis with elevated serum cobalt levels
. Cold flow (creep) deformation over time
. Early catastrophic failure from stripe wear

Correct Answer & Explanation

. Audible squeaking during range of motion

Explanation

Ceramic-on-ceramic bearings offer excellent wear characteristics but are uniquely associated with "squeaking" (an audible noise) in a small percentage of patients. This is often related to edge loading, micro-separation, or resonance within the hardware components.

Question 6333

Topic: 3. Adult Reconstruction (Hip & Knee)

An 8-year-old boy with spastic diplegic cerebral palsy presents for routine hip surveillance. Radiographs show a Migration Percentage of 50% bilaterally with an intact Shenton line, but a neck-shaft angle of 155 degrees. What is the best management strategy?

. Observation with serial radiographs every 6 months
. Bilateral adductor tenotomies alone
. Varus derotational osteotomy (VDRO) and pelvic osteotomy
. Bilateral total hip arthroplasty
. Proximal femoral resection (Girdlestone procedure)

Correct Answer & Explanation

. Varus derotational osteotomy (VDRO) and pelvic osteotomy

Explanation

A migration percentage over 40-50% in an older child with CP indicates severe hip subluxation and bony dysplasia. Soft tissue release alone is inadequate; VDRO combined with a pelvic osteotomy is required to restore joint congruency.

Question 6334

Topic: 3. Adult Reconstruction (Hip & Knee)



A 60-year-old male with a history of recurrent painful joint attacks presents with chronic deformities of his toes. Radiographs are obtained. What is the radiologic hallmark of this condition?

. Marginal erosions with profound periarticular osteopenia
. Punched-out lytic lesions with overhanging sclerotic margins
. Subchondral cysts with asymmetric joint space narrowing and osteophytes
. Pencil-in-cup deformity with acro-osteolysis
. Central erosions with a gull-wing appearance

Correct Answer & Explanation

. Punched-out lytic lesions with overhanging sclerotic margins

Explanation

Chronic tophaceous gout classically presents on radiographs with punched-out lytic lesions and overhanging sclerotic margins, often referred to as 'rat bite' erosions. Unlike rheumatoid arthritis, joint spaces are typically preserved until very late in the disease process, and periarticular osteopenia is absent.

Question 6335

Topic: 3. Adult Reconstruction (Hip & Knee)

A 62-year-old male with a history of gout undergoes an elective total knee arthroplasty. On postoperative day 3, he develops acute, severe pain, swelling, and erythema of the operated knee. Aspiration yields cloudy fluid with 35,000 WBCs/mm3 and negatively birefringent crystals. Gram stain is negative. What is the most appropriate next step?

. Immediate open arthrotomy and polyethylene exchange
. Intravenous vancomycin and cefepime
. Initiation of indomethacin or systemic steroids
. Initiation of allopurinol 300mg daily
. Two-stage revision arthroplasty

Correct Answer & Explanation

. Initiation of indomethacin or systemic steroids

Explanation

Acute postoperative gout flares can closely mimic acute periprosthetic joint infection. The presence of negatively birefringent crystals and a negative Gram stain supports acute gout, which is initially managed medically with NSAIDs or corticosteroids, avoiding unnecessary surgery.

Question 6336

Topic: Total Hip Arthroplasty (THA)

The Paley multiplier method is used to predict leg length discrepancy at maturity. What demographic variable is the standard multiplier strictly dependent upon?

. Current weight
. Chronological age and sex
. Skeletal age and sex
. Bone age independently
. Height percentiles

Correct Answer & Explanation

. Chronological age and sex

Explanation

The Paley multiplier method is primarily based on chronological age and sex. It is a simple and highly accurate tool for predicting limb length discrepancy at maturity, avoiding the need for bone age calculations in most congenital cases.

Question 6337

Topic: Total Hip Arthroplasty (THA)

A 12-year-old boy is undergoing deformity correction for a mid-diaphyseal tibial procurvatum deformity. According to Paley's Rule 1 of osteotomy, if the osteotomy and the axis of correction of angulation (ACA) are both located at the center of rotation of angulation (CORA), what will be the radiographic outcome of the correction?

. Pure angulation occurs without translation of the bone segments.
. Angulation occurs with obligatory translation of the bone segments at the osteotomy site.
. The mechanical axis will remain deviated parallel to the anatomical axis.
. Translation occurs without angulation, creating a bayonet apposition.
. The correction will induce an iatrogenic leg length discrepancy.

Correct Answer & Explanation

. Pure angulation occurs without translation of the bone segments.

Explanation

Osteotomy Rule 1 states that when the osteotomy and the ACA are placed at the CORA, pure angulation occurs. The mechanical and anatomical axes are realigned without any translation at the osteotomy site.

Question 6338

Topic: Total Hip Arthroplasty (THA)

An 8-year-old girl presents with a congenital femoral deficiency. Her current leg length discrepancy (LLD) is 3.0 cm. Using the Paley Multiplier method, and knowing the multiplier for a girl at age 8 is approximately 1.5, what is her predicted LLD at skeletal maturity?

. 2.0 cm
. 3.0 cm
. 4.5 cm
. 6.0 cm
. 7.5 cm

Correct Answer & Explanation

. 4.5 cm

Explanation

The Paley Multiplier method predicts limb length discrepancy at maturity by multiplying the current discrepancy by a chronological age- and sex-specific multiplier. In this case, 3.0 cm x 1.5 = 4.5 cm.

Question 6339

Topic: Total Hip Arthroplasty (THA)

A 15-year-old patient is undergoing distraction osteogenesis for a 4 cm tibial leg length discrepancy using an Ilizarov circular fixator. At the 4-week clinic visit, radiographs show premature consolidation of the regenerate bone at the osteotomy site. Which of the following technical errors most likely contributed to this complication?

. A latency period of 3 days prior to distraction.
. A distraction rate of 1.5 mm per day.
. Performing the osteotomy with a Gigli saw rather than a drill and osteotome.
. A distraction rate of 0.5 mm per day.
. Rhythm of distraction set to 0.25 mm four times a day.

Correct Answer & Explanation

. A distraction rate of 0.5 mm per day.

Explanation

Premature consolidation occurs when the bone heals faster than it is pulled apart, most commonly due to a distraction rate that is too slow (e.g., 0.5 mm/day) or a latency period that is too long. The standard distraction rate is typically 1 mm/day divided into 4 increments.

Question 6340

Topic: Total Hip Arthroplasty (THA)

A 9-year-old girl presents with a congenital leg length discrepancy (LLD). Her current discrepancy is 3 cm. According to the Paley Multiplier Method, the multiplier for a girl at age 9 is 1.4. Assuming no surgical intervention, what is her anticipated LLD at skeletal maturity?

. 3.0 cm
. 3.5 cm
. 4.2 cm
. 5.0 cm
. 5.6 cm

Correct Answer & Explanation

. 4.2 cm

Explanation

The Paley Multiplier Method predicts limb length discrepancy at maturity by multiplying the current discrepancy by an age- and gender-specific multiplier. For this patient: 3 cm x 1.4 = 4.2 cm.

Test Yourself

Switch to an interactive, timed exam simulation to truly master this topic.

On this Page