Osteoarthritis

Osteoarthritis is a common problem for many people after middle age. Osteoarthritis is sometimes referred to as degenerative arthritis, or wear and tear arthritis.

The main problem in osteoarthritis is degeneration of the articular cartilage that covers the joint. This results in areas of the joint where bone rubs against bone. Bone spurs may form around the joint as the body's response.

Osteoarthritis may result from an injury to the knee earlier in life. Fractures involving the joint surfaces, instability from ligament tears, and meniscal injuries can all cause abnormal wear and tear of the knee joint. Not all cases of osteoarthritis are related to prior injury, however. Research has shown that some people are prone to develop osteoarthritis, and this tendency may be genetic.

Osteoarthritis develops slowly over several years. The symptoms of osteoarthritis are mainly pain, swelling, and stiffening of the knee. The pain of osteoarthritis is usually worse after activity. Early in the course of the disease, you may notice that your knee does fairly well while walking, then after sitting for several minutes the knee becomes stiff and painful. As the condition progresses, pain can interfere with even simple daily activities. In the late stages, the pain can be continuous and even affect sleep patterns. This pain probably does not come from the covering of the joint, the articular cartilage, because this tissue does not have a nerve supply.

Sources of pain may be due to inflammation in the lining of the joint, called the synovium, small fractures in the bone under the cartilage, the subchondral bone, pressure from blood in the area, stretching of nerve endings over a bone spur.