Hand and Wrist Injury
Common and some not-so-common injuries of the small joints of the hands and wrists.
The bones, connective tissue and small joints of the hands and wrists are prone to several types of injuries. These injuries can happen in otherwise healthy joints – for example, a blow to the finger causes it to bend backward or jamming a finger causes the tendons to pull away from the bone. In other cases, a disease process may make an injury more likely. For example, wrist bones weakened by osteoporosis are prone to fracture. The following are some of the more common hand and wrist injuries.
Flexor Tendon Injuries
The flexor tendons are long strands of connective tissue that connect muscles in the forearm to the small bones of the finger and thumb, enabling them to move. If one of these tendons is severely injured the finger it connects to cannot move.
The most common causes of flexor tendon injuries are cuts and sports injuries. Flexor tendons may also rupture spontaneously in people with rheumatoid arthritis.
Extensor Tendon Injuries
Injuries to the extensor tendons (tendons on the backs of the hands and fingers that enable fingers and thumbs to straighten) can result in a number of different problems. The most common are:
- Mallet finger – a drooping of the end of the finger that occurs when an extensor tendon becomes separated from the bone. This can happen if the finger is cut or jammed. It is also called baseball finger.
- Boutonniere deformity – a deformity in which the joint in the middle of the finger (proximal interphalangeal joint or PIP) bends toward the palm and the joint closest to the nail (distal phalangeal joint or DP) bends upward. It can result from a cut or tear of the extensor tendon at the middle joint, a blow to the bent finger or damage from rheumatoid arthritis.
Other hand and finger injuries:
- Finger dislocations. If a finger is hit or bent back beyond its normal range of motion, it can become dislocated, meaning the ends of the bones move so that they are no longer properly aligned. Any of the finger joints can be dislocated.
- Finger fractures. Finger fractures can result from a number of causes, including jamming a finger, falling on it or closing it in a car door. Regardless of how it happens, the result can be the same: pain, swelling, inability to move the finger, and in some cases, deformity.
- Wrist fractures. A common cause of wrist fracture is stopping a fall with outstretched arms. Although anyone of any age can fracture a wrist this way, the risk is greater in people whose bones are weakened due to osteoporosis.
Wrist fractures may be classified as either Colles' fractures or Smith's fractures. Both are breaks of the radius (the bone of the forearm) near the wrist. The difference is in the way the bone is broken. A Colles' fracture occurs when the bone is broken with the hand outstretched. A Smith's fracture (sometimes called a reverse Colles' fracture) occurs when the hand is flexed and the back of the hand is hit.