Knee joint: Bursae and extracapsular ligaments (anterior view) (Latin)

Knee bursae are small fluid-filled sacs whose function is to reduce friction and accommodate gliding of muscles or tendons as they cross over bony prominences of the knee joint (art. genus). Two groups of bursae are associated with the knee joint : bursae around the patella (anterior/patellar ligaments) and bursae located elsewhere. The nonpatellar group consists of a group of superficial bursae, most notable being the bursa subtendinea inferior musculi bicipitis femoris and bursa anserina. The former is located on the lateral side of the joint, between the tendon of musculus biceps femoris and lig. collaterale fibulare genus. The bursa anserina is found on the medial side, cushioning the space between the lig. collaterale tibiale genus and combined tendinous expansions of the m. sartorius, m. gracilis and m. semitendinosus (pes anserinus).As many as fourteen bursae may be present, including the bursa subtendinea tractus iliotibialis found between tibia and the distal part of the tractus iliotibialis.The ligg. extracapsularia genus are located outside the capsula articularis. They are the lig. patellae, lig. collaterale fibulare, lig. collaterale tibiale, lig. popliteum arcuatum and obliquum (depicted on the posterior view).