The wrist is vulnerable to fracture in a fall, by direct trauma, or due to repetitive motion. This article details the four most common sports-related wrist fractures.
The wrist is the most complex joint in the body. The wrist joint includes the ends of the long bones of the forearm (the radius and ulna), eight small bones in the middle of the joint (the carpal bones), and the bottoms of the bones in the palm of the hand (the bases of the metacarpals). Any of these bones can fracture as a result of sports-related trauma. The most common sports fractures of the wrist are:
- Colles’ fracture
- Smith, or “reverse” Colles’, fracture
- Scaphoid fracture
- Fracture of the “hook” of the hamate
Colles’ Fracture
A Colles’ fracture is a break in the end of the radius, the forearm bone adjacent to the thumb. A Colles’ fracture is an angulated fracture, with the articulating surface of the bone angled away from its normal position. Colles’ fractures are usually the result of a fall on an outstretched hand. Colles’ fractures are usually seen in sports where a fall on a hard surface is likely, such as skating (in line skating, and ice skating), basketball, and hockey. Protective equipment, such as commercially available wrist guards, can help prevent Colles’ fractures.
Smith (Reverse Colles’) Fracture
A Smith fracture, like a Colles’ fracture, involves the end of the radius. However, the angulation of the end of the bone is in the opposite direction of a Colles’ fracture (hence the name “reverse Colles’ fracture”). The mechanism of injury of a Smith fracture is different from that of a Colles’ fracture. Smith fractures usually result from direct trauma to the back of the wrist, such as a direct blow from a stick, as in hockey or lacrosse. Smith fractures can also result from a fall on a flexed wrist.
Scaphoid Fracture
The scaphoid is one of the eight small carpal bones located in the mid portion of the wrist. The scaphoid is located immediately adjacent to the end of the radius, and extends to the base of the first metacarpal (near the thumb). The scaphoid is vulnerable to fracture due to its location and its orientation across the wrist joint. Scaphoid fractures occur as a result of a fall on an outstretched hand, similar to the mechanism of injury for a Colles’ fracture. Scaphoid fractures, however, tend to occur in younger individuals, whose long bones are stronger and are less likely to fracture. The force of the trauma is absorbed by the scaphoid in younger people, rather than the radius, which remains intact. Scaphoid fractures are especially problematic, as they may result in permanent damage to a portion of the fractured bone due to disruption of its normal blood supply (a process called “avascular necrosis”). Avascular necrosis results in chronic wrist pain, and early onset of arthritis.
Fracture of the Hook of the Hamate
The hamate is a carpal bone of the wrist located opposite the thumb. The normal hamate contains a bony outgrowth, known as the “hook”. This portion of the hamate bone is vulnerable to stress fracture due to repetitive motion from swinging a club, racquet or bat. Alternatively, the hook of the hamate may be fractured by direct trauma. Fractures of the hook of the hamate are troublesome, due to the likelihood of damage to the adjacent ulnar artery and nerve.
