What Is Osteoarthritis?
Osteoarthritis (OA) is the leading cause of disability in the USA. It is estimated that 1 out of 3 adults will suffer from arthritis. By definition osteoarthritis or degenerative joint disease (DJD) is a progressive disorder involving inflammation and degradation of the articular or hyaline cartilage on the ends of bones in various joints of the body. This type of cartilage has no nerve supply and is very resistant to friction making it perfect for weight bearing surfaces. When OA begins, the affected cartilage usually develops small tears in the joint surfaces that begin to progress into larger more substantial areas of wear. In normal joints, articular cartilage is capable of repairing minor wear in a limited capacity through chondrocyte production (cells that form new cartilage). When the damage rate becomes too significant and continuous, these cells can no longer repair the affected area. When this happens the process of degenerative joint disease begins. As this disease progresses, eventually the cartilage will wear out to a point where the underlying bone becomes exposed. This subchondral bone is rich in nerve supply and unlike hyaline cartilage is very prone to further wear from friction When this happens in a joint, the bones connecting the joint rub together resulting in pain and joint inflammation. This is where the term “bone on bone” comes from. As OA progresses, the affected joint will begin to form bone spurs around the joint margins and eventually lead to a noticable angular deformity at the joint. Although it is primarily found in weight bearing joints (knees and hips), it also occurs in non-weight bearing joints such as the shoulder.
DJD symptoms usually begin as stiffness (especially in the AM), pain with prolonged weight-bearing or immediately following activity, swelling, crepitus (audible grinding or ratcheting) and loss of motion. Symptoms vary from person to person and joint to joint.This joint is a ball and socket joint and is the most stable joint in the body. In hip arthritis, the two affected joint surfaces are the femoral head and the hip socket known as the acetabulum.
Symptoms of OA in the hip are commonly groin pain with occasional buttock or lateral hip pain. Stiffness with rotating the leg in and out as well a stiffness going from the seated to standing position are also common