Biomechanics & Biomaterials MCQs

In designing an intramedullary nail, if the solid cross-sectional radius of the nail is increased by 10%, how is its torsional rigidity affected?

A ligament graft used for anterior cruciate ligament (ACL) reconstruction elongates over time when subjected to a constant physiological load. This time-dependent biomechanical property is best described as:

A surgeon decides to use a solid intramedullary nail instead of a hollow nail of the same outer diameter. According to the polar moment of inertia, how does increasing the inner diameter (hollowing the nail) affect its torsional rigidity?

A patient requires revision of a femoral shaft fracture nonunion. The original stainless steel plate is left in place, and a titanium screw is used for supplementary fixation. Which of the following processes is most likely to occur at the interface of these two metals?

Polymethylmethacrylate (PMMA) is utilized for implant fixation in a cemented total knee arthroplasty. Which of the following statements regarding the properties of PMMA is accurate?

Which of the following best describes the mechanical behavior of cortical bone, whereby its strength and stiffness increase as the rate of loading increases?

Cortical bone demonstrates different mechanical properties depending on the direction of the applied load. It is stronger in longitudinal compression than in transverse loading. Which biomechanical term best defines this property?

A surgeon plans to perform a revision fixation using a stainless steel plate adjacent to an existing titanium screw. Which of the following complications is most likely to occur due to the combination of these two different metals in a physiologic environment?

Which of the following non-collagenous bone matrix proteins is vitamin K-dependent and plays a major role in regulating bone mineralization by binding to calcium and hydroxyapatite?

In a stress-strain curve for a metallic implant, the point at which the material ceases to deform elastically and begins to deform permanently is known as which of the following?

Rank the following materials in order of decreasing Young's modulus (stiffness):

On a standard stress-strain curve for cortical bone, the specific point at which the material ceases to deform elastically and begins to undergo permanent plastic deformation is defined as the:

A polyethylene component of a total knee prosthesis subjected to a constant physiological load over time undergoes a progressive increase in strain (deformation). This viscoelastic biomechanical phenomenon is known as:

Which of the following combinations of orthopedic implant materials is most strongly contraindicated for direct contact due to the high risk of clinically significant galvanic corrosion?

An orthopedic implant subjected to cyclic loading below its ultimate tensile strength eventually fractures due to microcrack propagation. What term describes the maximum stress level below which a material can endure an infinite number of cycles without failure?

Which of the following correctly ranks common orthopedic materials from the highest to the lowest Young's modulus (stiffness)?

Tendons and ligaments exhibit viscoelastic properties. Which of the following terms describes the phenomenon where the load required to maintain a constant deformation decreases over time?

On a stress-strain curve for cortical bone, the area under the entire curve up to the point of failure represents which of the following mechanical properties?