| Semimembranosus muscle | |
|---|---|
 Muscles of the gluteal and posterior femoral regions (semimembranosus labeled at bottom left) | |
| Details | |
| Origin | Ischial tuberosity |
| Insertion | Medial condyle of tibia |
| Artery | Profunda femoris and gluteal arteries |
| Nerve | Tibial part of sciatic nerve (L5, S1 and S2) |
| Actions | Extension of hip and flexion of knee |
| Antagonist | Quadriceps muscle and tensor fasciae latae |
| Identifiers | |
| Latin | musculus semimembranosus |
| TA98 | A04.7.02.036 |
| TA2 | 2642 |
| FMA | 22438 |
| Anatomical terms of muscle | |
The semimembranosus muscle (/ˌsɛmiˌmɛmbrəˈnoʊsəs/) is the most medial of the three hamstring muscles in the thigh. It is so named because it has a flat tendon of origin. It lies posteromedially in the thigh, deep to the semitendinosus muscle. It extends the hip joint and flexes the knee joint.