Author: Dr Peter de Souza
Last modified: 7 November 2022

The biceps femoris muscle is one of the 3 muscles of the posterior compartment of the thigh. The posterior compartment muscles of the thigh are collectively referred to as the "hamstrings", and function to extend the thigh at the hip joint, and flex the leg at the knee joint.

The biceps femoris lies laterally within the posterior compartment, and as the name suggests, has two "heads" - a long head which originates from the pelvic bone, and a short head which originates from the femoral shaft.

The other two muscles of the posterior compartment are the semimembranosus and the semitendinosus.


  • Long head: ischial tuberosity
  • Short head: linea aspera and lateral supracondylar ridge of femur


  • Fibula head
  • Lateral tibial condyle


  • Flexion of knee
  • Lateral rotation tibia
  • Extension of hip (long head only)


  • Long head: tibial nerve (L5, S1, S2)
  • Short head: common peroneal nerve (L5, S1, S2)

Blood Supply

  • Profunda femoris artery
  • Popliteal artery
  • Inferior gluteal artery