Corpus: Semimembranosus muscle: Unterschied zwischen den Versionen

The semimembranosus muscle is a skeletal muscle that belongs to the flexors of thigh muscles.

Origin

The semimembranosus muscle originates on the posterior surface of the ischial tuberosity, medial to the point of origin of the long head of the biceps femoris muscle.

Attachment

The attachment of the semimembranosus muscle is extensive and includes the medial condyle of the tibia, the fascia of the popliteus muscle, the oblique popliteal ligament, and the posterior side of the joint capsule of the knee. The semimembranosus bursa is located between the muscle insertion and the tibia.

Similar to the superficial pes anserinus formed by the insertion tendons of three muscles, the insertion of the semimembranosus muscle is also known as the deep pes anserinus.

In some cases, the muscle may be absent or form a unit with the semitendinosus muscle. The oblique popliteal ligament is also not always present.

The semimembranosus muscle is innervated by the tibial nerve.

The arterial supply is provided by the medial circumflex femoral artery, a branch of the deep femoris artery, and the popliteal artery.

The semimembranosus muscle functions to flex the knee joint, extend the hip joint, and support the internal rotation of the tibia.