Semitendinosus

Summary

Origins

• Ischial tuberosity of the pelvis

Insertions

• Proximal medial surface of the tibia (pes anserinus)

Actions

• Extends the hip
• Flexes the knee
• Medially rotates the leg when the knee is flexed

The semitendinosus runs along the inner hamstring. Its upper half is thick muscle, but it thins into a long tendon halfway down the thigh. It starts on the ischial tuberosity of the pelvis, travels beside biceps femoris, and slips behind the knee to reach the upper inner tibia.

Together with sartorius and gracilis, its pes anserinus attachment helps steady the leg against side-to-side sway. The muscle extends the hip, bends the knee, and turns the tibia inward when the knee is flexed, giving artists a clear cord to follow in active poses.

References

• Wikipedia