The subcutaneous prepatellar bursa lies between the skin of the knee and the patella, permitting movement of the skin. The knee, like other freely movable joints, has closed, fluid-filled sacs called bursae associated with it. Each bursa has an inner lining of synovial membrane, which may be continuous with the synovial membrane of a nearby joint cavity. Bursae act as cushions and aid the movementmycontentbreak of tendons that glide over such bony parts or over other tendons. The names of the bursae indicate their locations; for example, a suprapatellar bursa, a prepatellar bursa, and a infrapatellar bursa.