Summary Biceps femoris short head Origin Lateral lip of linea aspera, lateral supracondylar ridge of femur, and lateral intermuscular septum of thigh Insertion Primarily on fibular head; also on lateral collateral ligament and lateral tibial condyle Action Flexes the knee, and also rotates the tibia laterally; long head also extends the hip joint Innervation Common peroneal nerve (L5, S1, S2) Arterial supply Perforating branches of profunda femoris artery, inferior gluteal artery, and the superior muscular branches of popliteal artery