Arthritis can affect any joint in the body, but it is most visible when it strikes the hands and fingers. Arthritis of the hand can be both painful and disabling. The most common forms of arthritis in the hand are osteoarthritis and rheumatoid arthritis.

Causes
Osteoarthritis is a degenerative joint disease in which the cushioning cartilage that covers the bone surfaces at joints begins to wear out. It may be caused by simple "wear and tear" on joints, or it may develop after an injury to a joint. In the hand, osteoarthritis most often develops in three sites: at the base of the thumb, where the thumb and wrist come together (the trapezio-metacarpal joint); at the middle joint of a finger (the proximal interphalangeal or PIP joint); and at the finger tip (the distal interphalangeal or DIP joint).

Rheumatoid arthritis affects the cells that line and normally lubricate the joints (synovial tissue). It is a systemic condition, which means that it affects multiple joints, usually on both sides of the body. The joint lining (synovium) becomes inflamed and swollen. The swollen tissue may stretch the surrounding ligaments, which are connective tissues that hold bones together, resulting in deformity and instability. The inflammation may also spread to the tendons, which are the connective tissues that link muscles and bones. This can result in tears (ruptures) in the tendons. Rheumatoid arthritis of the hand is most common in the wrist and finger knuckles (the metacarpophalangeal or MP joints).

Symptoms
Stiffness, swelling, loss of motion, and pain are symptoms common to both osteoarthritis and rheumatoid arthritis in the hand. With osteoarthritis, bony nodules may develop at the middle joints of one or more fingers (Bouchard's nodes) and at the finger tip (Heberden's nodes). The joints become enlarged and the fingers crooked. In rheumatoid arthritis, some joints may be more swollen than others. There is often a sausage-shaped (fusiform) swelling of the finger. Other symptoms of rheumatoid arthritis of the hand include a soft, lumpy mass over the back of the hand; a creaking sound (crepitus) during movement; a shift in the position of the fingers as they drift away from the direction of the thumb; and inflammation of the finger tendons, resulting in a permanent bending (Boutonnière) deformity. In addition, there may be a "swan's neck" deformity caused by hyperextension (sway-back) at the middle joint of the finger associated with a bent fingertip.

Treatment
Treatment is designed to relieve pain and restore function. Treatment decisions are based on the type of arthritis you have, its progression and its impact on your life. Anti-inflammatory medications such as aspirin or ibuprofen may help reduce swelling and relieve pain; prescription medications or steroid (cortisone) injections may be recommended. Your physician may refer you to a physical or occupational therapist because changing the way you do things with your hands may help relieve pain and pressure.

If you have osteoarthritis, your physician may recommend a period of rest. You may also be advised to wear finger or wrist splints at night and for selected activities. Surgery is usually not advised unless these treatments fail. If that is the case, however, several surgical options are available:

• Surgery may be used to drain or remove the cysts associated with the nodes and to remove excess bone growth.
• Joint fusion (stiffening the problem joint) may be used to correct deformities that interfere with functioning or that are cosmetically unacceptable.
• A joint replacement may be advised.

If you have rheumatoid arthritis in your hands, medications can help decrease inflammation, relieve pain and retard the progress of the disease. Rest, controlled exercise, and wearing finger or wrist splints may also be part of your treatment program.  Rheumatoid arthritis often affects the connective tissues (tendons) as well as the joints. The tendons that become inflamed may rupture. If this happens, you may be unable to bend or straighten your fingers or to grip properly. In certain cases, specific preventive surgery may be recommended.