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Semimembranosus muscle.png
Muscles of the gluteal and posterior femoral regions (semimembranosus labeled at bottom left)
Muscle Type
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 degrees), extends hip joint (less than biceps femoris)
Synergists Quadriceps Femoris
Spinal innervation L5, S1, S2
Peripheral Innervation Tibial Nerve
Vasculature Inferior gluteal artery, perforating arteries, popliteal artery