This condition involves deterioration of the articular cartilage of the knee. The most common cause of osteoarthritis (OA) is prolonged mechanical breakdown and loss of the smooth articular cartilage layers of your knee joint. These changes are progressive and typically worsen over time.
Articular Cartilage has no blood supply, and virtually no healing properties. Excessive impact, shear stress, or long term wear-and-tear creates cracking, ulceration, and eventually erosion of cartilage down to the underlying bone. When bone is exposed, increased pain is often noted. High friction results in inflammation and bone spur development. Lower leg deformities, such as becoming knock-kneed, or bow-legged, may occur.
X-Rays are essential in the diagnosis of OA. Bone spurs, loose pieces, and loss of space between the bones all indicate that the articular cartilage has been lost. MRI scans may be helpful, but are not essential, unless your physician suspects loose pieces that may require surgery, which would not otherwise be performed.
Typical symptoms include persistent pain, and stiffness, catching or grinding, decreased range of motion, and swelling in the knee. These symptoms limit your walking distance and alter your activity level as well as your general health.