1. General Principles & Basic Science MCQs

Rituximab is a biologic disease-modifying antirheumatic drug (DMARD) occasionally utilized in patients with refractory Rheumatoid Arthritis. What is the specific cellular target of Rituximab?

In biomechanical evaluation of tendons, the phenomenon where a tendon subjected to a constant displacement demonstrates a gradual decrease in measured tension over time is best described by which of the following terms?

Demineralized bone matrix (DBM) is widely used in orthopedic surgery to augment fracture healing and spinal fusion. DBM relies primarily on which of the following biological properties?

The introduction of highly cross-linked polyethylene in total hip arthroplasty has dramatically reduced wear rates. However, the process of cross-linking using irradiation negatively impacts the mechanical properties of the polyethylene. Which step is most commonly added to the manufacturing process to eliminate free radicals and prevent in vivo oxidation?

A surgeon plans to use a stainless steel screw with a titanium plate for fracture fixation. Which of the following best describes the primary mechanism of early implant failure associated with this specific metallurgical combination?

Absolute stability with interfragmentary compression is achieved in a transverse radial shaft fracture using a dynamic compression plate. Which of the following histological processes is predominantly responsible for the subsequent bone healing?

A 65-year-old male presents with increasing head size and bowing of his tibiae. Radiographs show thickened cortices and a "cotton wool" appearance of the skull. Which of the following describes the primary cellular defect initiating this condition?

In normal articular cartilage, which zone contains the highest concentration of collagen, with fibrils specifically arranged parallel to the joint surface to resist shear forces?

A patient sustains a severe stretch injury to a peripheral nerve resulting in loss of axonal continuity and endoneurial tube disruption, but preservation of the perineurium and epineurium. According to Sunderland's classification, what grade is this injury?

In the pathogenesis of orthopedic implant-related infections, which of the following describes the crucial step mediating the irreversible attachment of Staphylococcus aureus to an implant surface?

A 45-year-old woman with untreated celiac disease presents with diffuse bone pain and proximal muscle weakness. Laboratory studies reveal low serum calcium, low phosphorus, elevated alkaline phosphatase, and elevated parathyroid hormone. Which of the following is the most likely diagnosis?

During the biological repair process of a surgically repaired flexor tendon, at which time point post-repair does the site typically reach its lowest tensile strength, rendering it most susceptible to iatrogenic rupture?

A 55-year-old male presents with a severely painful, swollen first metatarsophalangeal joint. Joint aspiration yields negatively birefringent, needle-shaped crystals under polarized light microscopy. Which of the following medications is most appropriate for the acute management of his symptoms?

During a voluntary concentric muscle contraction, calcium ions are released from the sarcoplasmic reticulum into the sarcoplasm. To initiate the sliding filament mechanism, these calcium ions must directly bind to which of the following proteins?

A 32-year-old female presents with progressive knee pain. Radiographs reveal an eccentric, lytic, epiphyseal lesion in the distal femur. Biopsy shows mononuclear cells and numerous multinucleated giant cells. Which targeted medical therapy is most appropriate for an unresectable lesion of this type?

According to Wolff's Law, bone remodels in response to mechanical stress. Which of the following mechanical properties accurately describes bone's ability to exhibit different stiffness and strength depending on the speed (rate) at which a load is applied?