Hand fractures involve the bones that form part of the wrist (carpals), bones of the palm (metacarpals), or bones of the fingers and thumb (phalanges). Normal hand function results from a complex interaction of an intricate arrangement of muscles, tendons, ligaments, and joints, as well as bones. Thus, seemingly minor fractures can cause serious soft tissue injuries that, if not treated appropriately, can lead to disabling stiffness, weakness, or deformity.
A carpal bone that is commonly fractured is the scaphoid bone (see Hand Disorders: Common Hand Injuries). A fracture of the scaphoid bone usually occurs with a fall on an outstretched hand. Symptoms include pain while rotating the palm and, particularly, tenderness at the hollow at the base of the thumb or pain when the thumb is pushed into the wrist. Because the initial x-ray is often normal, people who have a suspected fracture require splinting and re-examination in 7 to 10 days, or magnetic resonance imaging (MRI), which is more sensitive than an x-ray. The fracture may be treated with a thumb spica splint. Scaphoid bone fractures are prone to poor healing because the blood supply is often damaged when the bone is fractured. About 5% of the time, regardless of treatment, the bone eventually dies (called necrosis). If so, bone grafting may be necessary.
Fractures of the ends of the 4th and 5th metacarpal bones (that attach to the ring finger and little finger) commonly occur from punching a hard object. This type of fracture, called a boxer's fracture, causes swelling and tenderness of the knuckle. These fractures are treated with a splint. Reduction is necessary only if the fracture is badly angled or rotated. Typically, good function of the finger returns.
Avulsion fractures occur commonly in the fingers at the site of tendon and joint capsule attachments. A mallet finger injury refers to the drooping of the fingertip that occurs when the tendon that extends the farthest part of the finger becomes detached (see Hand Disorders: Mallet Finger). A common cause is a baseball that strikes the fingertip (baseball finger). For simple mallet finger injuries, immobilization with a splint for 6 to 10 weeks is effective, but if avulsion fractures greatly disrupt the joint surface, surgery may be needed.
Fingertip fractures are usually the result of a crush injury, such as from a hammer blow. Blood may accumulate beneath the nail (subungual hematoma) from a tear in the nail bed and produce a very painful, blue-black discoloration. Most fingertip fractures are treated with a protective covering (such as commercially available aluminum and foam splint material) wrapped around the fingertip. Doctors can easily drain a subungual hematoma by making a small hole in the fingernail with a needle or a hot wire (electrocautery device).
Large, displaced finger fractures are repaired with surgery. An abnormal increase in sensitivity (hyperesthesia) frequently lasts long after a large fracture has healed. The person may require treatment to decrease hyperesthesia (desensitization therapy).
Last full review/revision December 2008 by James R. Roberts, MD