3. Adult Reconstruction (Hip & Knee) MCQs

In the mechanism of aseptic loosening following total joint arthroplasty, the biologic cascade triggered by polyethylene wear debris is primarily initiated by which of the following cell types phagocytosing the particles?

A 55-year-old patient who underwent total hip arthroplasty with a ceramic-on-ceramic bearing surface two years ago now complains of a loud, audible squeaking sound from the hip during normal walking. Which of the following biomechanical factors is most strongly associated with the initiation of this phenomenon?

Highly cross-linked polyethylene (HXLPE) was introduced in total hip arthroplasty to reduce osteolysis secondary to wear debris. Which of the following is a known adverse biomechanical consequence of increasing the radiation dose to maximize polyethylene cross-linking?

During a posterior approach to the hip for total hip arthroplasty, the preservation or meticulous repair of which of the following structures has been shown in the literature to be most critical in minimizing the risk of postoperative posterior dislocation?

A 50-year-old active male undergoes a total hip arthroplasty using a ceramic-on-ceramic bearing. Which of the following is the most notable disadvantage or complication specific to this bearing surface?

During a posterior-stabilized total knee arthroplasty (PS-TKA), the cam-post mechanism is designed to substitute for which resected structure?

When utilizing an uncemented total hip arthroplasty, the surgeon aims to achieve initial mechanical stability to promote osseointegration. What is the commonly accepted maximum threshold of micromotion at the bone-implant interface beyond which fibrous tissue formation predictably occurs instead of bone ingrowth?

Staphylococcus aureus is a predominant pathogen in periprosthetic joint infections. Which bacterial surface protein plays a critical role in evading the host immune system by binding to the Fc portion of IgG?

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  Which of the following neurovascular structures is at greatest risk during the introduction of acetabular component fixation screws during total hip replacement?

In total hip arthroplasty, increasing the perpendicular distance from the

center

line of the femur to the center of rotation of the femoral head (femoral offset) results in

A 65-year-old male presents with groin pain 5 years after undergoing an uncomplicated primary total hip arthroplasty utilizing a large diameter CoCr head on a titanium stem. Radiographs show a well-fixed stem and cup with no osteolysis. Laboratory tests show elevated serum cobalt levels, normal ESR, and normal CRP. Joint aspiration yields opaque fluid with negative cultures. What is the most likely diagnosis?

Which of the following is a recognized unique complication specific to ceramic-on-ceramic total hip arthroplasty bearing surfaces compared to other bearing options?

In modern total hip arthroplasty, highly cross-linked polyethylene (HXLPE) is commonly used to reduce wear rates. Which of the following manufacturing processes is utilized to eliminate free radicals generated during the cross-linking process and prevent subsequent in vivo oxidation?

A 68-year-old female presents with a painful total knee arthroplasty 2 years postoperatively. Aspiration reveals a synovial fluid WBC count of 35,000 cells/mcL with 92% PMNs. Components are well-fixed on radiographs. Which of the following is the most appropriate definitive management?

In total hip arthroplasty, the use of highly cross-linked polyethylene (HXLPE) has significantly reduced wear rates. Which of the following mechanical trade-offs is a direct consequence of increasing the radiation dose to maximize cross-linking?

A 68-year-old male presents with a painful total knee arthroplasty 3 years post-operatively. Which biomarker, measured in synovial fluid, directly binds to and neutralizes microbial cell membranes and is highly specific for periprosthetic joint infection?

During a primary posterior-stabilized total knee arthroplasty, the surgeon uses spacer blocks and notes that the knee is tight in flexion but balanced and stable in extension. Which of the following is the most appropriate next step to balance the knee?

The introduction of highly cross-linked polyethylene (HXLPE) in total hip arthroplasty has drastically reduced the incidence of osteolysis primarily by decreasing which specific mechanism of wear?

A 55-year-old active male underwent a total hip arthroplasty (THA) utilizing a ceramic-on-ceramic bearing surface. Two years postoperatively, he complains of an audible, high-pitched squeaking sound during hip movement, though he is generally pain-free. Which of the following technical factors is most strongly associated with this phenomenon?

A 68-year-old female presents with catching and a painful 'pop' at the anterior aspect of her knee when extending from a flexed position. This symptom began 14 months after she underwent a primary total knee arthroplasty (TKA). What is the most likely underlying etiology of her symptoms?