Total Hip Arthroplasty (THA) MCQs

A 65-year-old man undergoes primary total hip arthroplasty using a ceramic-on-ceramic bearing. At 2-year follow-up, he reports an audible squeaking sound from the hip during ambulation. What is the most significant biomechanical risk factor for this phenomenon?

A 40-year-old male bodybuilder feels a tearing sensation in his anterior elbow while lifting a heavy object. He has an abnormal Hook test. Operative repair is planned via a two-incision technique. Which complication is most uniquely associated with the two-incision technique compared to a single-incision anterior approach?

C orrection of the congenital gibbus in spina bifida must follow which of these surgical principles:

During a primary total hip arthroplasty (THA) using a posterior approach, the surgeon inadvertently places the acetabular component in excessive retroversion. Which of the following complications is this patient at greatest risk for developing postoperatively?

A 68-year-old patient undergoes a primary total hip arthroplasty (THA). Over the next 6 months, the patient experiences recurrent anterior hip dislocations. Which of the following combinations of component positioning is the most likely biomechanical cause of these recurrent anterior dislocations?

During a primary total hip arthroplasty through a posterior approach, the surgeon successfully increases the femoral offset by 8 mm using an extended offset stem without altering the vertical limb length. Which of the following is the most direct biomechanical consequence of this geometric change?

You are planning a primary total hip arthroplasty on a 45-year-old female with bilateral Crowe IV developmental dysplasia of the hip (DDH). To bring the femoral component down to the true acetabulum without causing severe sciatic nerve traction, you perform a transverse subtrochanteric shortening osteotomy. Which of the following femoral stem choices is absolutely critical to maximize the union rate of this osteotomy?

A 70-year-old female presents with severe lateral hip pain and an unremitting Trendelenburg gait two years after a THA via a Hardinge (direct lateral) approach. MRI demonstrates a massive, complete tear of the gluteus medius and minimus tendons with Goutallier Grade 4 fatty infiltration of the muscle bellies. What is the most reliable reconstructive surgical option to restore active abduction?

A 50-year-old female presents with persistent anterior groin pain exacerbated by active straight leg raising six months after an uncemented THA. Radiographs demonstrate well-fixed components with ideal alignment, appropriate version, and no anterior acetabular overhang. An ultrasound-guided injection of local anesthetic into the iliopsoas bursa provides complete, temporary pain relief. If conservative management fails, what is the best initial surgical intervention?

Ceramic-on-ceramic (CoC) bearings in THA are highly desirable due to extremely low wear rates but are associated with an audible 'squeaking' complication. Which biomechanical factor has been most strongly correlated with the development of squeaking in CoC hips?

A 45-year-old active male underwent a total hip arthroplasty (THA) 3 years ago. He presents to the clinic complaining of a high-pitched squeaking noise coming from his hip during flexion, such as when bending over to tie his shoes. Radiographs show well-fixed components. What is the most likely risk factor or etiology for this clinical presentation?

A patient with a primary THA complains of recurrent posterior dislocations. Component analysis via advanced imaging reveals that the acetabular cup is positioned in 20 degrees of abduction and 0 degrees of anteversion. What is the most appropriate primary surgical strategy to address this instability?

During a primary THA, the surgeon considers options for the modular femoral head. Increasing the femoral neck length without changing the neck-shaft angle of the stem will have which of the following biomechanical effects?

A 72-year-old female presents to the emergency room with a posterior dislocation of her THA. The index surgery was performed 4 weeks ago via a posterior approach. She states she dropped a pen and bent over deeply at the waist to pick it up. A successful closed reduction is performed in the ER. Post-reduction radiographs confirm the cup is positioned at 40 degrees of inclination and 20 degrees of anteversion. What is the most appropriate next step in management?

Intraoperatively during a primary THA using trial components, the surgeon performs a 'shuck' test (longitudinal traction) and notes excessive joint laxity of 8 mm. However, when the legs are placed parallel in full extension, clinical assessment clearly indicates that the operative leg is already 1.5 cm longer than the contralateral leg. The components are stable in extreme range of motion without impingement. To restore soft tissue tension without further exacerbating the leg length discrepancy, what is the optimal surgical adjustment?

A 54-year-old male with end-stage hip osteoarthritis has a concomitant 2.5 cm leg length discrepancy (the operative leg is shorter). During THA, the surgeon lengthens the leg by 2.5 cm to restore symmetry. Postoperatively, the patient develops a foot drop and parasthesias in the lateral lower leg. Electromyography (EMG) performed 4 weeks later would most likely demonstrate which finding if a stretch injury to the sciatic nerve occurred?

In total hip arthroplasty (THA), utilizing the posterior approach carries a higher risk of postoperative dislocation compared to the direct anterior approach. Which of the following anatomical structures is primarily repaired to mitigate this risk?

During a posterior approach to the hip (Kocher-Langenbeck), the medial circumflex femoral artery (MCFA) is at risk. Prior to branching to supply the femoral head, the main vessel classically passes between which two muscles posteriorly?

A surgeon is performing a primary THA using a direct lateral (Hardinge) approach. Which of the following structures is at greatest risk of denervation if the proximal split in the gluteus medius exceeds 5 cm from the greater trochanter?

A patient complains of a severely elongated leg immediately after a primary THA. Radiographs demonstrate an increased vertical distance from the teardrop to the lesser trochanter compared to the native contralateral side, with symmetric femoral offset. Which specific intraoperative error most likely occurred?