OA is principally a disease of the joints. As a consequence, its symptoms include pain, swelling, and stiffness of the joints.
The pain associated with OA usually has an insidious onset, is generally described as aching or throbbing, and may result from changes that have occurred over the last 15 to 20 years. It is usually worsened by activity and improved by rest. As the disease progresses and the joint becomes more damaged, the pain may become constant. This pain does not come from an irritation of the cartilage (which contains no nerves), but rather from the adjacent tissues that are stretched or inflamed.
Joint stiffness is another cardinal finding in OA. Morning stiffness can be found in all types of arthritis. This stiffness usually lasts about 30 minutes with OA, compared to an hour or more for rheumatoid arthritis. Many people with OA notice that their joints become stiff after they remain in the same position for long periods of time, such as after sitting or driving. Doctors sometimes call this type of stiffness “gelling.” A few minutes of movement typically dispels this type of stiffness. The symptoms of stiffness can be improved by taking nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen or indocin, or by taking a hot shower or bath.
Swelling of the joints is another classic feature of OA. It is caused by changes in the bone and fluid in the joint. The progressive destruction of the cartilage “cushion” leads to the release of chemicals that affect the bones of the joint. The ends of the bones can enlarge and form bony growths (bone spurs). These growths increase the appearance of joint enlargement or “knobbiness.” An increase in the amount of joint fluid present also contributes to joint swelling. The erosion of cartilage results in an inflammation of the lining of the joint (called the synovial membrane). The synovial membrane produces excess fluid that collects in the joint, and this fluid production can increase with increased exercise or joint injury. As this fluid buildup can cause increased pressure and pain, doctors sometimes remove it to relieve symptoms.
Synovial membrane
Connective tissue that lines the cavity of a joint and produces synovial fluid.
OA typically affects the joints of the hand—principally the middle knuckle joints, the distal knuckle joints (next to the fingernail), and the base of the thumb. The hips, knees, feet (especially the big toe), neck, and low back are other common sites for OA. Finger joints affected by OA exhibit a hard bony swelling called Heberden's nodes. Sometimes early in the course of the disease there may be redness around the affected joint, similar to that seen with rheumatoid arthritis. Your doctor can usually tell the two types of arthritis apart, even without taking x-rays. In more advanced cases of OA, patients may experience a decreased range of motion in the affected joints.
Heberden's nodes
Knobby overgrowths of the joint nearest the fingertips in patients with osteoarthritis.
Arthritis of the hip or knee affects a person's ability to get up or down from a seated position as a result of pain and stiffness. The change from sitting to standing puts more weight on your hips and knees than walking or standing; thus, the lower the seat, the harder it becomes to stand up. Many people describe great difficulty getting up, but after they are up they can walk. Purchasing chairs with higher seats and arm rests can help overcome this difficulty.
When OA strikes the spine, it can lead to pain and stiffness in the neck or low back. People with spinal OA complain of pain when they turn their heads or touch their toes. In addition, advanced spinal OA can produce bone spurs along the vertebrae. These bone spurs can pinch nerves along the spine, resulting in numbness and tingling of the hands or feet.
Secondary (indirect) problems created by OA include anxiety or depression, feelings of helplessness or dependence on others, and decreased ability to perform activities of daily living or work.