Practice Set 1 of 88
This practice set contains high-yield board review questions covering key concepts in Biomechanics & Biomaterials. Each clinical scenario is designed to test your diagnostic and management skills relevant to this subspecialty.
During medial ulnar collateral ligament (UCL) reconstruction via the docking technique, where is the precise isometric point for the ulnar tunnel placement?
. At the sublime tubercle
During normal knee kinematics, the popliteus muscle plays a vital role in initiating knee flexion from a fully extended position. What is its primary biomechanical action during this phase?
. External rotation of the femur on the tibia in a closed chain
During a total hip arthroplasty, the surgeon opts to use a highly cross-linked polyethylene liner to reduce wear rates. What is the primary mechanism by which cross-linking improves the tribological properties of the polyethylene?
. Using irradiation to create covalent bonds between adjacent polymer chains
A medial meniscus posterior root tear alters knee biomechanics by causing which of the following?
. Biomechanical equivalence to a total medial meniscectomy
During anterior cruciate ligament (ACL) reconstruction, tensioning the graft at which of the following knee flexion angles most closely restores intact knee kinematics when using a single-bundle construct?
. 20 to 30 degrees of flexion
A 45-year-old male undergoes arthroscopy for a medial meniscal tear. Biomechanically, an unrepaired posterior root tear of the medial meniscus most closely approximates the tibiofemoral contact pressures seen in which of the following conditions?
. Total meniscectomy
What is the most common serious systemic complication associated with the injection of polymethylmethacrylate (PMMA) during vertebroplasty?
. Pulmonary cement embolism
During a percutaneous vertebroplasty, what volume of PMMA injection is generally sufficient to achieve significant pain relief and stabilization in a typical thoracolumbar vertebral body?
. 2 to 4 cc
The polymethylmethacrylate (PMMA) utilized in percutaneous vertebroplasty has which of the following distinct properties when compared to standard joint arthroplasty cement?
. Extended working time
What is the recommended definitive management for an adult patient diagnosed with a confirmed adamantinoma of the tibia?
. Wide en bloc resection and reconstruction
The phenomenon whereby a ligament or tendon demonstrates increasing length over time under a constant applied load is known as:
. Creep
Which element is specifically added to stainless steel alloys (e.g., 316L) to improve their resistance to pitting corrosion in the chloride-rich environment of the human body?
. Molybdenum
Which of the following antibiotics is most frequently added to polymethylmethacrylate (PMMA) bone cement due to its broad-spectrum efficacy and thermal stability during the exothermic polymerization process?
. Tobramycin
During laboratory biomechanical testing of a human tendon, the tendon is rapidly stretched to a specific length and held constantly at that length. Over time, the internal force required to maintain this stretch gradually decreases. What is this specific viscoelastic phenomenon called?
. Stress relaxation
In orthopedic basic science, viscoelastic materials like ligaments and tendons exhibit 'creep' when loaded. Which of the following best defines the phenomenon of creep?
. Time-dependent continuous deformation under a constant load
Which biomechanical property of titanium makes it highly advantageous for use in uncemented orthopedic implants compared to stainless steel or cobalt-chrome alloys?
. Lower modulus of elasticity
An 80-year-old woman is undergoing a cemented hemiarthroplasty for a displaced femoral neck fracture. Immediately upon cement pressurization and stem insertion, her end-tidal CO2 abruptly drops, and she becomes severely hypotensive. What is the most likely cause?
. Bone cement implantation syndrome
A 45-year-old male presents with acute knee pain. Aspiration yields 40 mL of cloudy fluid. Cell count reveals 65,000 WBCs/mm3 with 85% polymorphonuclear leukocytes. Crystals are negatively birefringent under polarized light. What is the most likely composition of these crystals?
. Monosodium urate
Ligaments and tendons exhibit viscoelastic properties. Which of the following best describes the phenomenon where a tissue subjected to a constant deformation experiences a gradual decrease in stress over time?
. Stress relaxation
A 21-year-old athlete undergoes an Achilles tendon repair. Postoperatively, the biomechanical property of the tendon where it deforms gradually over time under a constant load is known as:
. Creep