- Anatomy:
- origin: upper and lower aspect of ischial tuberosity:
- insertion: posterior surface of medial condyle of the tibia;
- action: flexes and medially rotates the calf at the knee. extends, adducts and medially rotates the thigh at the hip;
- semimembranous is especially important as stabilizing structure around the posterior and posteromedial aspects of the knee;
- reversed origin-insertion action: when the leg is fixed, gives posterior stability to the pelvis and extends the pelvis on the hip;
- nerve supply: sciatic (tibial branch), L4, L5, S1, S2: (see innervation);
- synergists: semitendinosus, biceps, gastrocnemius, gracilis, sartorius;
- 5 distal expansions;
- oblique popliteal ligament :
- tendinous attachment is to post capsule & post horn of medial meniscus;
- anterior portion passing beneath the MCL to insert on tibia;
- insertion to posterior oblique ligament;
- expansion to aponeurosis of popliteus muscle;
- Semimembranous Tendinitis:
- is predominant in males;
- average age of onset is 32 years;
- inflammation at the insertion site of direct head of semimembranous tendon into the area of the posterior tubercle of the tibia can be detected by
increased activity on a bone scan in that region
Semimembranous tendinitis: An overlooked cause of medial knee pain.
Surgical Repair of Complete Proximal Hamstring Tendon Rupture.
The Anatomy of the Posterior Aspect of the Knee An Anatomic Study.