Muscle Anatomy


The semitendinosus muscle is part of the posterior compartment of the thigh, situated medially. It is one of the hamstring muscles and contributes to the musculature at the back of the thigh. It is a long and slender muscle.

Originating from the ischial tuberosity, the semitendinosus takes its starting point from the bony prominence on the posterior aspect of the hip bone.

The muscle inserts into the superior part of the medial surface of the tibia, specifically at the pes anserinus. This insertion site establishes a connection with the proximal part of the shinbone.

Functionally, the semitendinosus is a powerful flexor of the knee joint and plays a role in medial rotation of the tibia. It is actively engaged in movements like bending the knee, such as during walking or running, and contributes to the stability of the knee joint. Additionally, the muscle is involved in hip extension, aiding in movements where the thigh moves backward. The semitendinosus is integral to the coordinated actions of the hamstring muscles and their role in lower limb biomechanics.