Osteoarthritis. X-ray of the elbow of a 69-year- old woman with osteoarthritis. The elbow is where the upper-arm bone (humerus, upper right) meets the two bones of the forearm: the radius (upper) and the ulna (lower). Normally, the bones are separated by friction-reducing cartilage. Here, however, the cartilage has been worn away, causing the joint space to become narrowed. This makes the joint stiff and painful. Osteoarthritis is a common joint disease that affects many people over the age of 60. More women than men suffer from severe osteoarthritis. Symptoms can be relieved with painkilling and anti-inflammatory drugs, and physiotherapy, although surgery may be necessary.