Kienbock's Disease (Avascular Necrosis of the Lunate)

Kienbock's disease is a condition where the cells of one of the bones of the hand and wrist (lunate bone) die, because of a lack of blood supply. The reason Kienbock's disease occurs is not known, but most people believe it is due to repeated small injuries (trauma) that interrupt blood supply to the area.

SYMPTOMS

  • Wrist pain and tenderness.

  • Loss of motion at the wrist.

  • Wrist stiffness.

  • Swelling in the wrist (uncommon).

  • Decreased grip strength.

CAUSES

The cause of Kienbock's disease is disputed. Most people believe it is due to repeated small injuries (trauma) that interrupt blood supply to the area. It is unknown whether or not falling on an outstretched wrist is associated with the disease. Another risk factor may include having a forearm bone on the little finger side (ulna) shorter than the bone of the thumb side (radius). This causes greater stress across the wrist, to the lunate bone.

RISK INCREASES WITH:

  • Long radius bone.

  • Repeated wrist injury.

  • Dominant wrist.

  • Age between 20 and 40 years.

PREVENTION

There are no known preventative measures.

PROGNOSIS

The outcome for Kienbeck's disease varies, and will depend on how early it is diagnosed and treated.

RELATED COMPLICATIONS

  • Longer healing time, if usual activities are resumed too soon.

  • Frequently recurring symptoms.

  • Prolonged impairment (sometimes).

  • Wrist stiffness or weakness.

  • Arthritis of the wrist.

TREATMENT

First, treatment involves ice and medicine, to reduce pain and inflammation. It is advised that the wrist be restrained, to prevent further injury. After restraint, stretching and strengthening exercises are needed, to regain strength and a full range of motion. These exercises may be done at home or with a therapist. Many cases of Kienbeck's disease require surgery. The surgical procedure will depend on the extent of damage. It may include either shortening the radius, or removing the lunate bone.

MEDICATION

  • If pain medicine is needed, nonsteroidal anti-inflammatory medicines (aspirin and ibuprofen), or other minor pain relievers (acetaminophen), are often advised.

  • Do not take pain medicine for 7 days before surgery.

  • Prescription pain relievers are often prescribed only after surgery. Use only as directed and only as much as you need.

HEAT AND COLD

  • Cold treatment (icing) should be applied for 10 to 15 minutes every 2 to 3 hours for inflammation and pain, and immediately after activity that aggravates your symptoms. Use ice packs or an ice massage.

  • Heat treatment may be used before performing stretching and strengthening activities prescribed by your caregiver, physical therapist, or athletic trainer. Use a heat pack or a warm water soak.

SEEK MEDICAL CARE IF:

  • Pain, swelling, or bruising gets worse, despite treatment, or persistent pain lasting more than 2 to 4 weeks.

  • You experience pain, numbness, discoloration, or coldness in the hand or fingers, or blue, gray, or dark fingernails.

  • Any of the following occur after surgery: increased pain, swelling, redness, drainage of fluids, bleeding in the affected area, or signs of infection, including fever.

  • New, unexplained symptoms develop. (Drugs used in treatment may produce side effects.)