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

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

Origin

  • Ischial tuberosity

Insertion

  • Proximal medial tibial shaft (with gracilis and sartorius to form the collective pes anserinus insertion)

Action

  • Flexion of knee
  • Extension hip
  • Medial rotation of tibia (esp. when knee flexed)

Innervation

  • Tibial nerve: L5, S1, S2

Blood Supply

  • Profunda femoris artery
  • Popliteal artery
  • Inferior gluteal artery