3. Adult Reconstruction (Hip & Knee) MCQs

A 72-year-old female sustains a displaced femoral neck fracture after a mechanical fall. She is at high risk for avascular necrosis of the femoral head. Disruption of which of the following vessels is primarily responsible for this complication?

A 68-year-old male undergoes a total hip arthroplasty via a posterior approach for severe osteoarthritis. Postoperatively, he is counseled on hip precautions to prevent the most common early complication. Which combination of hip movements places this patient at the highest risk for this complication?

A 75-year-old female presents to the emergency department after a mechanical fall. On examination, her right lower extremity is shortened and externally rotated. Radiographs reveal a displaced intracapsular femoral neck fracture. If this fracture is treated with internal fixation, which of the following is the most significant complication associated with this specific injury?

During a total knee arthroplasty (TKA), after making the initial bony cuts and inserting trial components, the surgeon observes that the knee is excessively tight in flexion but perfectly balanced in extension. Which of the following surgical interventions is the most appropriate next step to correct this mismatch?

During a posterior-stabilized total knee arthroplasty for a severe varus deformity, the surgeon notes the knee is balanced in flexion but remains tight medially in extension. Which of the following structures should be released next to correct this specific asymmetry?

A 28-year-old female with a known history of Multiple Epiphyseal Dysplasia (MED) presents with severe, debilitating bilateral hip pain. Radiographs show end-stage secondary osteoarthritis of both hips with flattened femoral heads, loss of joint space, and incongruent joints. What is the most appropriate definitive management?

A 14-year-old male with Multiple Epiphyseal Dysplasia presents with bilateral hip pain. Radiographs show flattened, irregular capital femoral epiphyses with early signs of secondary osteoarthritis, but the acetabula are relatively well-preserved. If surgical intervention is considered to prolong the lifespan of the native hip, which of the following is the most appropriate rationale for an intertrochanteric osteotomy in this patient?

A 28-year-old female with a known diagnosis of Multiple Epiphyseal Dysplasia (MED) presents with severe, bilateral hip pain that limits her daily activities. Radiographs show advanced bilateral hip osteoarthritis with flattened femoral heads, but her acetabular depth is relatively preserved. Spine radiographs are normal. Which of the following is the most appropriate surgical intervention?

A 32-year-old patient with Autosomal Dominant Multiple Epiphyseal Dysplasia (MED) presents with end-stage hip osteoarthritis and requires bilateral total hip arthroplasties (THA). Which of the following intraoperative challenges is most characteristic for this specific patient population?

A 35-year-old male with a documented history of Multiple Epiphyseal Dysplasia (MED) presents with progressive, severe joint pain. He has symmetrical involvement of his shoulders, hips, and knees. Which joint is most likely to require the earliest arthroplasty in the natural history of this condition?

A 75-year-old female with a history of osteoporosis sustains a mechanical fall and presents with severe left groin pain. Her left lower extremity is shortened and externally rotated. Radiographs demonstrate a completely displaced, subcapital femoral neck fracture. She is independently ambulatory and lives alone. Which of the following surgical interventions is most appropriate to minimize the risk of reoperation and optimize her functional recovery?

A 78-year-old female with osteoporosis trips on a rug and falls onto her left hip. She is unable to bear weight. In the emergency department, her left lower extremity is noted to be shortened and externally rotated. Radiographs confirm a displaced intracapsular fracture of the proximal femur. What is the most significant complication associated with this specific fracture pattern if treated with internal fixation?

A 72-year-old female sustains a displaced femoral neck fracture. She is at high risk for avascular necrosis of the femoral head due to disruption of its primary blood supply. Which of the following vessels provides the predominant blood supply to the weight-bearing dome of the femoral head in an adult?

A 72-year-old female sustains a displaced femoral neck fracture after a mechanical fall. She is scheduled for a hemiarthroplasty. The high rate of avascular necrosis and nonunion associated with this fracture pattern, if treated with internal fixation, is primarily due to disruption of which of the following vessels?

A 72-year-old female sustains a displaced femoral neck fracture after a mechanical fall. She is scheduled for a hemiarthroplasty due to the high risk of avascular necrosis. Which of the following vessels provides the predominant blood supply to the adult femoral head, which is disrupted in this injury?

A 68-year-old male undergoes a primary total hip arthroplasty via a posterior approach for severe osteoarthritis. Six weeks postoperatively, he sustains a posterior dislocation while bending over to tie his shoes. To minimize the risk of this complication during the index procedure, the acetabular component should ideally be placed within the "safe zone." Which of the following represents the classic Lewinnek safe zone for acetabular cup positioning?

During a posterior-stabilized total knee arthroplasty, the trial components are placed. The knee is tight in flexion but balanced in extension. Which of the following adjustments is most appropriate to balance the knee?

In modern total hip arthroplasty, highly cross-linked polyethylene (HXLPE) is frequently infused with Vitamin E (alpha-tocopherol). What is the primary biochemical purpose of adding Vitamin E to the polyethylene?

A 65-year-old male undergoes a primary total hip arthroplasty using a highly cross-linked polyethylene liner. During the manufacturing process, the polyethylene is subjected to gamma irradiation followed by remelting. Which of the following best describes the biomechanical effect of the remelting process?

During a primary total knee arthroplasty, the surgeon assesses the gap kinematics with trial components in place. The extension gap is symmetric and perfectly balanced, but the flexion gap is tight. Which of the following adjustments is the most appropriate next step?