Total Hip Arthroplasty (THA) MCQs

A 55-year-old female presents with groin pain 5 years after a metal-on-metal THA. Labs show elevated cobalt and chromium. MARS MRI shows a large cystic mass. What histologic finding is most characteristic of this condition?

A 55-year-old active male undergoes THA with a ceramic-on-ceramic bearing. At 2 years postop, he complains of a squeaking noise with deep flexion. Radiographs show a well-fixed cup. What is the most significant risk factor for this phenomenon?

A 65-year-old woman presents with persistent lateral hip pain and a severe Trendelenburg gait 1 year after a THA via a lateral (Hardinge) approach. MRI demonstrates a chronic, full-thickness, completely retracted tear of the gluteus medius and minimus with severe fatty infiltration. What is the most appropriate surgical management?

During a posterior (Kocher-Langenbeck) approach to the hip, protection of the main blood supply to the femoral head is critical. The deep branch of the medial femoral circumflex artery (MFCA) courses between which two muscles?

During a direct lateral approach (Hardinge) to the hip, the gluteus medius is split. What is the precise anatomic footprint of the gluteus medius tendon insertion on the greater trochanter?

During a posterior approach to the hip, protecting the medial circumflex femoral artery (MFCA) is critical. The main branch of the MFCA runs most consistently between which two muscles before piercing the hip capsule?

During a posterior approach to the hip (Kocher-Langenbeck), which two muscles form the interval where the deep branch of the medial circumflex femoral artery is most at risk?

A 9-year-old girl with a history of right femoral shaft fracture treated non-operatively now has a 3 cm leg length discrepancy. According to the multiplier method, which of the following data points is strictly required to predict her discrepancy at skeletal maturity?

A 10-year-old girl is evaluated for a leg length discrepancy following a distal femoral physeal fracture 2 years ago. A scanogram reveals the injured limb is 3 cm shorter than the normal limb. Based on the multiplier method, her predicted leg length discrepancy at maturity is 4.5 cm. Which of the following is the most appropriate surgical management plan?

Figure 14 shows the radiograph of an 80-year-old male presenting with thigh pain. Radiographs demonstrate a periprosthetic fracture around a loose femoral stem with poor proximal bone stock. What is the most appropriate management?

A 58-year-old male undergoes a direct anterior approach THA. Postoperatively, he complains of burning pain and numbness over the anterolateral aspect of his thigh, but his quadriceps motor function is completely intact. Which nerve was most likely injured during the surgical exposure?

Increasing femoral offset during total hip arthroplasty without changing the vertical leg length will have which of the following biomechanical effects?

A 72-year-old woman presents with severe groin pain 10 years after THA. Radiographs show a medialized acetabular component with a fracture line through the Kohler line and inferior translation of the lower half of the hemipelvis. What is the most appropriate classification and treatment concept for this defect?

A patient experiences recurrent posterior dislocations of their total hip arthroplasty, especially when rising from a low chair. Radiographic evaluation shows the acetabular component is placed in 25 degrees of anteversion and 40 degrees of inclination. The femoral stem is retroverted by 10 degrees. What is the primary cause of instability?

During a posterior approach to the hip, what is the key anatomical structure that serves as the posterior border of the gluteus medius and protects the superior gluteal neurovascular bundle from injury?

A 55-year-old woman complains of new-onset severe groin pain with active straight leg raise 1 year after an uncomplicated THA. A diagnostic injection of bupivacaine into the psoas bursa under ultrasound guidance completely relieves her pain. What is the most likely radiographic finding associated with this condition?

A 68-year-old man undergoes a primary right THA. At his 6-week postoperative visit, he complains his right leg feels "too long." Clinical exam reveals level anterior superior iliac spines (ASIS) with block testing, but the patient perceives a prominent discrepancy. What is the most appropriate initial management?

An 80-year-old patient with advanced Parkinson's disease requires a primary THA for severe osteoarthritis. To minimize the significant risk of postoperative dislocation in this specific patient population, which acetabular component design modification is most appropriate?