Tuesday, October 4, 2011

Biceps Femoris Muscle

The biceps femoris is a muscle located on the posterior (back) side of the femur (thigh bone). Its long head originates from the tuberosity of the ischium, and its short head arises from the lower half of the lateral lip of the linea aspera inserting into the head of the fibula. The long head of the biceps femoris is innervated by the tibial nerve, which is a branch of the sciatic nerve; the short head is innervated by the common peroneal nerve, which has origin from the dorsal branches of the fourth and fifth lumbar. The biceps femoris flexes knee joint and rotates the leg laterally.