Arthritis literally means “inflamed joint”. Normally a joint consists of two smooth, cartilage-covered bone surfaces that fit together as a matched set and that move smoothly against one other. Arthritis results when these smooth surfaces become irregular and don’t fit together well anymore and essentially “wear out.” Arthritis can affect any joint in the body, but it is most noticeable when it affects the hands and fingers. Each hand has 19 bones, plus 8 small bones and the two forearm bones that form the wrist. Hand arthritis can be both painful and disabling. The most common forms of arthritis in the hand are osteoarthritis, post-traumatic arthritis (after an injury), and rheumatoid arthritis. Other causes of hand arthritis are infection, gout, and psoriasis.
Osteoarthritis is a degenerative joint disease in which the cushioning cartilage that covers the bone surfaces at the 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 (see Figure 1):
It also often develops in the wrist.
Stiffness, swelling, and pain are symptoms common to all forms of hand arthritis. With osteoarthritis, bony nodules may develop at the middle, or PIP, joint of the finger (Bouchard’s nodes), and at the end-joints, or DIP, of the finger (Heberden’s nodes) (see Figure 2). A deep, aching pain at the base of the thumb is typical of osteoarthritis of the basilar joint. Swelling and a bump at the base of the thumb where it joins the wrist may also be observed.
Grip and pinch strength may be diminished, causing difficulty with activities such as opening jars or turning keys. Pain, swelling, stiffness, and diminished strength are also seen with osteoarthritis of the wrist.