The knee joint is comprised of three main bones: the femur, or thigh bone; the tibia, or shin; and the patella, or knee cap. All of these structures are surrounded by cartilage and ligaments that support the knee joint and protect it from injury. The medial meniscus is a C-shaped cartilage structure that is attached to the tibia and acts as a shock absorber for the knee. The medial meniscus can be torn by twisting the knee violently or by the normal aging process. In either case, the result of a torn medial meniscus is pain and swelling in the knee and inability to straighten the leg. Repair to the medial meniscus typically involves surgery. The torn portion of the cartilage is removed and the remaining areas are smoothed out during a procedure called a meniscectomy. After surgery, physical therapy will be recommended so that the strength and flexibility will be regained. There are several potential complications associated with this procedure that should be discussed with a doctor prior to surgery.