Semimembranous   


- 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

The semimembranosus-tibial collateral ligament bursa. Anatomical study and magnetic resonance imaging.

Surgical Repair of Complete Proximal Hamstring Tendon Rupture.

The Anatomy of the Posterior Aspect of the Knee An Anatomic Study.



Original Text by Clifford R. Wheeless, III, MD.

Last updated by Data Trace Staff on Tuesday, April 10, 2012 4:33 pm