AnatoMemory

Muscle

Semimembranosus

Medial hamstring, broad tendon

Lower limbMuscular system

High-yield

Deep to semitendinosus; medially rotates the flexed leg. Tibial division of the sciatic nerve.

Overview

A medial hamstring deep to semitendinosus with a broad membranous proximal tendon, flexing the knee and extending the hip.

Reference facts

Origin
Ischial tuberosity
Insertion
Posterior part of the medial condyle of the tibia
Action
Flexes the knee, medially rotates the flexed leg, and extends the hip
Innervation
Tibial division of the sciatic nerve (L5, S1, S2)
Blood supply
Perforating branches of the deep femoral artery

Frequently asked questions

What does the semimembranosus do?

The semimembranosus flexes the knee, medially rotates the flexed leg, and extends the hip.

What nerve innervates the semimembranosus?

The semimembranosus is innervated by the tibial division of the sciatic nerve (L5, S1, S2).

Where does the semimembranosus attach?

The semimembranosus originates from the ischial tuberosity and inserts on the posterior part of the medial condyle of the tibia.

What is the blood supply of the semimembranosus?

The semimembranosus is supplied by the perforating branches of the deep femoral artery.