Degenerative Joint Disease
Degenerative diseases of the knee most often involve the cartilage that protects the knee joint.
Click on a condition below to learn more.
Also called chondromalacia patellae, this condition results from a softening of the cartilage within the kneecap to an extent that the kneecap no longer slides smoothly over the femur. It is most commonly seen in young adults and those who are active in sports. Initially it may be caused by trauma, overuse, mal-alignment of the knee, or muscle weakness. Over time, the problem may progress from minor irregularities in the surface of the cartilage to a bone surface that no longer has any cartilage protection. The problem may also develop from an injury such as a blow that causes the cartilage to tear and may also tear pieces of bone away from the knee.
The most common symptom of chondromalacia is a dull pain around or under the kneecap that increases when you walk up or down stairs or hills. First aid measures may bring temporary, symptomatic relief, however, it is usually recommended that a different type of activity be substituted for the one that is causing and aggravating the injury. It may also be helpful to follow a muscle-strengthening program to improve the stability of the joint. In some cases, arthroscopic surgery may be needed to re-shape the cartilage and remove any cartilage or bone fragments that may be loose in the joint. In more severe cases, surgery may be required to re-shape or re-align the kneecap.
Osteochondritis dissecans is a condition in which there is a loss or disruption of the blood supply to the bones of the knee joint. Gradually the cartilage loosens, and joint movement causes pain. The problem may arise spontaneously in an active adolescent or a young adult, and it may lead to early development of osteoarthritis. The condition may also be caused by a slight blockage of small artery or by an unrecognized injury that damage the overlying cartilage. If several joints are involved or several family members develop the same problem, it may be an inherited form of the disease. In some cases, the problem will resolve itself, but when cartilage separates from bone or a bone fragment breaks loose into the knee joint, there may be locking of the joint, joint weakness and pain.
Surgery may be used to stabilize the joint or to stimulate new blood vessel development. If bone fragments are loose, surgery may be used to clean the bone surfaces and supplement the joint with grafted cartilage.