1. General Principles & Basic Science MCQs

Tranexamic acid (TXA) is widely utilized in orthopedic surgery to reduce perioperative blood loss. Which of the following describes its exact mechanism of action?

Periprosthetic joint infections are notoriously difficult to eradicate due to bacterial biofilm formation. Which phase of biofilm development involves the production of a protective extracellular polymeric substance (EPS) or glycocalyx?

To minimize stress shielding around a femoral stem in total hip arthroplasty, the implant's stiffness should ideally match that of cortical bone. Which of the following lists materials in order of decreasing Young's modulus (from stiffest to most flexible)?

Platelet-rich plasma (PRP) relies on the degranulation of platelet alpha granules to release growth factors that promote tissue healing. Which of the following growth factors is NOT typically found in high concentrations within these alpha granules?

When a tendon is subjected to tensile loading, the initial portion of the stress-strain curve exhibits a non-linear 'toe region' before becoming linear. What physiological change at the microscopic level corresponds to this toe region?

During the correction of a pediatric clubfoot using the Ponseti method, the tightened ligaments gradually elongate over time under the constant applied load of the cast. This phenomenon is an example of which viscoelastic property?

During muscle contraction, the maximum force generated by a single motor unit depends heavily on the type of contraction performed. Which type of muscle contraction is capable of generating the greatest absolute peak force?

The tidemark of articular cartilage serves what primary function and is located between which two zones?

Sclerostin, an inhibitor of bone formation, exerts its effect by binding to LRP5/6 and directly inhibiting which of the following signaling pathways?

When a stainless steel screw is placed through a titanium plate, which type of corrosion is most likely to occur, and which metal will undergo accelerated oxidation?

When a constant force is applied to a ligament over time, the ligament will gradually undergo continuous elongation. This viscoelastic property is known as:

Which of the following best characterizes Type I muscle fibers compared to Type IIb fibers?

The pullout strength of a cortical screw is most significantly increased by maximizing which of the following parameters?

Demineralized bone matrix (DBM) primarily relies on which of the following components for its osteoinductive properties?

In a healthy diarthrodial joint, which type of lubrication mechanism predominates during high-load, low-speed activities such as standing from a chair?

The non-Newtonian, shear-thinning behavior of normal synovial fluid, where viscosity decreases as the shear rate increases, is primarily conferred by which of the following molecules?

A patient sustains a peripheral nerve injury resulting in Wallerian degeneration distal to the injury site, but the endoneurium, perineurium, and epineurium remain completely intact. According to Seddon's classification, this injury is best described as:

Which of the following physical characteristics must an antibiotic possess to be effectively mixed into and eluted from polymethylmethacrylate (PMMA) bone cement?

Absolute stability of a fracture construct (e.g., rigid plate fixation with compression) leads to primary bone healing. This process occurs via cutting cones and directly bypasses which typical phase of secondary fracture healing?