Musculus semimembranosus
Muscles of
the gluteal and posterior femoral regions with current muscle highlighted
The semimembranosus muscle is one of the hamstring muscles in the posterior compartment of the thigh and accompanies the semitendinosus muscle in the medial aspect of the posterior thigh. It is named for its flattened membranous tendon of its ischial attachment.
Its lateral border forms the superomedial border of the popliteal fossa.
Summary
- origin: ischial tuberosity
- insertion: infraglenoid tubercle of the posterior medial tibial condyle, posterior joint capsule (contributing to the oblique popliteal ligament), popliteal fascia and posterior horn of medial meniscus
- action
- flexes knee joint
- medially rotates knee joint (when the knee is flexed beyond 90)
- extends hip joint (less than biceps femoris)
- arterial supply
- inferior gluteal artery
- perforating arteries
- popliteal artery
- innervation: tibial nerve
- antagonist: quadriceps
Variant anatomy
- absent muscle
- accessory semimembranosus muscle