NCIt definition : A flat muscle located in the posterior compartment of the lower leg, which forms the
floor of the lower part of the popliteal fossa, and originates on the lateral femoral
epicondyle, with insertion on the posterior surface of the tibia, and which functions
to rotate the tibia medially on the femur or, when the tibia is fixed, rotates the
femur laterally on the tibia and provides dynamic stability to the posterolateral
part of the knee.;