About the semitendinosus
Its long tendon gives the muscle its name and is commonly harvested for anterior cruciate ligament reconstruction.
Clinical relevance
- Hamstring strains are common in sprinters, usually near the ischial attachment.
Semitendinosus: origin, insertion, nerve supply and action
Also called: hamstring
Quick answer
The semitendinosus is one of the three hamstring muscles on the back of the thigh. It arises from the ischial tuberosity and inserts on the upper medial tibia at the pes anserinus. The tibial part of the sciatic nerve supplies it, and it extends the hip and flexes and medially rotates the knee.
Key facts
| Origin | Ischial tuberosity. |
|---|---|
| Insertion | Superior part of the medial surface of the tibia (pes anserinus). |
| Innervation | Tibial part of the sciatic nerve (L5-S2). |
| Blood supply | Perforating branches of the profunda femoris and inferior gluteal artery. |
| Action | Extends the hip, flexes the knee and medially rotates the flexed knee. |
3D model: BodyParts3D (CC BY 4.0), adult male reference anatomy. Highlighted structure shown with nearby bones for context.
Frequently asked questions
Which muscles are the hamstrings?
Semitendinosus, semimembranosus and biceps femoris.
Where does the semitendinosus insert?
On the medial upper tibia at the pes anserinus.
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