Function of the Hand and Wrist

The human hand is an extremely complex and finely-balanced structure. There are more than 25 bones in the human hand and wrist. The wrist joint provides flexibility and strength for the hand to perform an infinite variety of tasks. The two major functions of the hand, shown at left, are (1) the pinch, which uses the thumb and index finger, and (2) the power grip, which usually involves closing the hand around an object. The wrist joint can extend upward or flex downward, and can move laterally from side to side (see illustrations at left).

Principle Causes of Wrist Pain

There are two principle reasons for wrist pain. A sudden event or an acute injury can break a bone or tear a ligament. Less apparent, but more slowly developing insidious causes of wrist pain are repeated patterns of activity, which over time may cause undue strain on the wrist. What can result is commonly referred to as Repetitive Strain Injuries, which include (1) Carpal Tunnel Syndrome, and (2) DeQuervain’s Disease.

Other potential causes of wrist pain include diabetes, thyroid disease, arthritis, and pregnancy (which can cause severe swelling and other wrist problems).

Traumatic Arthritis

The healing process which results from the traumatic stress of a sudden injury often causes arthritis. An accident occurs, and the bone or the connecting ligaments are broken or torn. After the broken bone fragments are realigned, even if the realignment appears to be perfect, there will still be some distortion. Over time, the broken bones will settle, increasing the distortion, and the surfaces of the bones will tend to rub and wear out. The cartilage lining on the end of the bones is especially susceptible to this “wearing out” process, and as the tissues and linings around the bone become irritated and swell, scarring will eventually occur. All of these relatively small changes will cause a greater degree of stress over time on the bones and the cartilage, and inevitably arthritis will result.

> Radius & Ulna Fractures
> Scaphoid Bone Fractures
> Carpal Tunnel Syndrome
> DeQuervain’s Disease
> Arthritis