GLOSSARY

The semitendinosus is a fusiform, superficial muscle on the medial back of the thigh whose lower half becomes a long, round tendon, which is where its name comes from.

Attachments and Innervation

• Origin: the ischial tuberosity, by a common tendon with the long head of biceps femoris.
• Insertion: the upper medial surface of the tibia, as part of the pes anserinus.
• Nerve: the tibial division of the sciatic nerve (L5–S2).

Structural Feature

The semitendinosus has a tendinous intersection (raphe) across the middle of its belly and, architecturally, long, parallel fascicles that suit it to high contraction velocity.

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