Which of the following statements about the "screw home" mechanism is true?
A. Hamstring muscle contraction leads to knee extension
B. Pes anserine muscle contractions leads to unlocking of the knee
C. Plantaris muscle contraction initiates knee rotation and flexion
D. Popliteus muscle contraction leads to rotation at the knee and the start of unlocking
E. Screw home mechanism cannot occur while the quadriceps muscles are relaxed
Answer: D
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Biomechanics
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