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Basic Science
intermediate
X-Type

Joint Reaction Forces

Joint Biomechanics

A registrar is reviewing biomechanics before the Part 1 examination. The consultant asks about the principles of lever arm mechanics as applied to the musculoskeletal system and how these affect joint loading during functional activities. Regarding lever arm mechanics and joint loading:

Mark each as TRUE or FALSE

A

A lever arm (moment arm) is the perpendicular distance from the line of action of a force to the axi...

B

Most joints operate as third-class levers where the muscle force is applied between the fulcrum (joi...

C

Muscle lever arms are typically longer than external load lever arms, giving muscles excellent mecha...

D

Because muscle lever arms are typically shorter than external load lever arms, muscles must generate...

E

Surgical procedures that increase moment arm (such as tibial tubercle transfer, high-offset hip pros...

Answer the questions to see explanations

Click T (True) or F (False) for each option