1. General Principles & Basic Science MCQs

Bone morphogenetic proteins (BMPs) primarily exert their osteoinductive cellular effects by initiating intracellular signaling through which of the following molecules?

Nitrogen-containing bisphosphonates are frequently used to alter bone metabolism in orthopaedic patients. They achieve their effect primarily by which of the following mechanisms?

Nitinol, commonly used in orthopaedic staples, stents, and suture anchors, is a shape-memory alloy composed primarily of which two elements?

Compared to conventional ultra-high-molecular-weight polyethylene (UHMWPE), highly cross-linked polyethylene used in total joint arthroplasty exhibits which of the following mechanical properties?

During material testing, a specimen undergoes a stress-strain analysis. The total area under the stress-strain curve up to the point of failure represents which of the following material properties?

A 70-year-old woman with severe osteoporosis is started on denosumab. This medication improves bone density by directly targeting and neutralizing which of the following?

Which of the following orthopedic implant materials possesses a modulus of elasticity most closely resembling that of human cortical bone?

According to Perren strain theory, what is the maximum allowable interfragmentary strain that permits primary (direct) bone healing to occur?

A patient undergoes revision of a metal-on-polyethylene total hip arthroplasty due to a grossly loose femoral stem. Intraoperatively, black debris and pitting are noted specifically at the modular head-neck junction.

What is the primary mechanism of this degradation?

During the incorporation of a massive structural cortical bone allograft, which cellular process occurs first during creeping substitution?

Polymethylmethacrylate (PMMA) bone cement is primarily utilized in total joint arthroplasty for implant fixation. Biomechanically, PMMA exhibits its greatest strength against which of the following forces?

A 65-year-old woman is prescribed teriparatide for severe osteoporosis. The anabolic effect of this medication on bone mass is primarily mediated by which of the following mechanisms?

Osteoclasts are responsible for bone resorption during remodeling. From which of the following cell lineages are mature osteoclasts derived?

During the clinical Lachman test, rapid translation of the tibia produces a stiffer response from the anterior cruciate ligament (ACL) than slow translation. This load-rate dependent behavior is characteristic of which material property?

Using a titanium screw through a 316L stainless steel plate in an aqueous physiologic environment increases the risk of which type of corrosion?

Which of the following constitutes the most abundant organic component of the extracellular matrix of human bone?

To reduce oxidative degradation of conventional UHMWPE after sterilization with gamma irradiation, modern manufacturing processes incorporate a thermal treatment known as remelting. What is the primary negative biomechanical consequence of this remelting process?

A 65-year-old active man undergoes a total hip arthroplasty using highly cross-linked polyethylene (HXLPE). While this material significantly reduces wear, the cross-linking and subsequent thermal melting processes reduce which of the following mechanical properties, predisposing thin components to failure?

To maximize the pullout strength of a cortical screw used in a diaphyseal fracture, which of the following design modifications is most effective?

A 60-year-old patient presents with a painful total hip arthroplasty 5 years after the index procedure. Aspiration is negative for infection. Revision surgery reveals black debris and macroscopic damage at the modular head-neck taper junction. Which type of corrosion is most likely responsible for this failure?