Biceps Femoris muscle:

Definition: This muscle of the posterior thigh flexes and laterally rotates the leg.

Origin: The long head originates from the ischial tuberosity and the short head from the lateral lip of the linea aspera along the posterior femoral shaft.

Insertion: There are 11 attachments of the biceps femoris complex at the knee ( Terry and LaPrade, 1996). The main tendinous attachments are to the fibular styloid ( direct arms of long and short heads, anterior arm of long head) and the anterolateral tibia ( anterior arm of short head).

Innervation: The tibial nerve innervates the long head and the common peroneal nerve innervates the short head.

Blood supply: Perforating branches of profunda femoris artery

1. Terry G.C., LaPrade, R.F.: The biceps femoris complex at the knee: Its anatomy and injury patterns associated with acute anterolateral-anteromedial rotatory instability. Am J. Sports Med., 24: 2-8, 1996.