The biceps femoris is a muscle within the posterior compartment of the thigh.
It has two heads (long head and short head) and is the most lateral of the muscles in the posterior thigh. The common tendon of the two heads can be felt laterally within the popliteal fossa (posterior knee region).
- Attachments:
- Long head originates from the ischial tuberosity of the pelvis.
- Short head originates from the linea aspera on posterior surface of the femur.
- The two heads form a tendon which inserts onto the head of the fibula.
- Actions: Flexion and lateral rotation of the knee. Weak extensor and lateral rotator of the thigh.
- Innervation:
- Long head is innervated by the tibial part of the sciatic nerve
- Short head is innervated by the common fibular part of the sciatic nerve.
- Blood Supply: Profunda femoris artery
By TeachMeSeries Ltd (2025)
Fig 2
Cross section of the thigh, showing the position of the major muscle groups.