Kienbock's Disease

Kienbock's disease is a disorder of the lunate bone which is located in the wrist. The cause of Kienbock's disease is not known. Some evidence suggests that in some people, an underlying poor blood supply to this bone is related. Other doctors have found that an altered bone alignment of the wrist is related. At some point the blood supply is diminished causing the bone to die. It usually happens to young people and is more common in men. People usually complain of progressively worsening wrist pain. Overtime swelling can also be present as well as limited wrist motion. A hand surgeon will help identify the problem with an exam and x-rays. There are situations in which a wrist MRI may give more information about the blood supply to the bone. A wrist CT scan is often needed to help plan surgery for severe cases.

Treatment for Kienbock's disease is based on how long the condition has been going on and the severity of the changes in the lunate bone. Overtime, as the bone loses blood supply it becomes weakened and the bone collapses. Early on before the bone has collapsed, surgery has been recommended to address abnormalities in bone alignment and blood supply. An abnormally long radius bone is thought to increase pressure on the lunate contributing to the disease. Shortening the radius helps to restore a more normal alignment. In patients with a normal radius, the capitate can also be shortened to reduce pressure on the lunate. Vascularized bone grafting involves moving a small portion of bone with its blood supply and placing it in the lunate to restore blood supply. If the lunate has collapsed, treatment to preserve the lunate is not as successful. Limited wrist bone fusion or removing the lunate with a proximal row carpectomy are options for severe cases. These procedures are designed to prevent wrist arthritis that occurs without treatment. When wrist arthritis develops a total wrist fusion is recommended.

Figure 1