•         Semimembranosus Muscle is a slender muscle and has a tendinous membrane like origin hence named so.
•         Semimembranosus Muscle is most medial of the Hamstring Muscle at the back of the Thigh.

ATTACHMENTS 

•         Origin : Semimembranosus Muscle arises from the Ischial Tuberosity over the lateral part of its Superior Aspect.
•         It runs between its anterior Aponeurosis and posterior Hamstring Muscles, downwards.
•         Insertion : Semimembranosus Muscle is inserted into the Medial Condyle of the Tibia and it also sends fibres for its attachment to the lateral and medial aspects of the Medial Condyle.

BLOOD SUPPLY 

Semimembranosus Muscle gets its blood via the branches of Profunda Femoris Artery and Gluteal Arteries.

NERVE SUPPLY 

Semimembranosus is innervated by the Tibial Nerve.

ACTION 

•         Semimembranosus Muscle extends the Hip Joint.
•         It also flexes the Knee joint.
•         Semimembranosus medially rotates the knee if its in semiflexed position.