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Disorders of the Hand & Upper Extremity > Keinböck's Disease What is Keinböck's Disease? Keinböck's disease, or osteonecrosis of the carpal lunate, is a condition affecting the lunate bone, one of the eight bones of the wrist attaching to the bones of the forearm and the bones of the hand. In this condition, the blood flow to the lunate bone is lost, usually causing the bone to die. Osteonecrosis (sometimes called osteochondrosis or osteochondritis) is a condition of defective bone formation in the growing portion of those parts of the bones that articulate with others to form joints. The lunate articulates with the radius, one of the long bones of the forearm. Keinböck's disease shows up in radiographic images as increased whiteness or density in the lunate bone compared with the surrounding bones. Untreated Keinböck's disease will almost always result in the collapse and destruction of the entire wrist joint, as the other small bones of the wrist become displaced by the degeneration of the lunate. Collapse of the wrist results in the permanent loss of grip strength and motion in the wrist. Keinböck's disease affects men more than women and usually occurs between the ages of 20 and 40 years. Causes of Keinböck's Disease? Keinböck's disease, like other manifestations of osteonecrosis, appears to be due to disturbed circulation in the epiphyses, or growing parts of the skeleton. When the blood supply to these portions of bone is lost or limited, a process called necrosis sets in and the bones degenerate. When the blood supply to the lunate is inhibited it begins to die. Sometimes patients have a history of injury prior to developing this condition, although a specific cause-and-effect relationship has not been established between Keinböck's disease and other injuries to the wrist. Symptoms of Keinböck's Disease? If you are suffering from Keinböck's disease, you will feel pain and stiffness in your wrist. There will be diffuse swelling over the back of the hand. Your hand and wrist may feel weak, and it may be difficult for you to grasp or grip objects. In later stages of this condition the lunate bone will fragment and collapse, causing generalized degenerative arthritis of the wrist. There may be degeneration at surrounding joints, where the lunate meets the scaphoid, triquetal, hamate, and capitate bones. Treatment of Keinböck's Disease? Your doctor will examine your hand and wrist. He or she will need to know if you have had previous injuries to the hand, wrist, or arm. X-rays will be taken. Your doctor will rule out the possibility that your pain may be caused by other conditions, such as arthritis, a fracture of the distal radius (one of the long bones of the arm as it joins the wrist), a fracture of the scaphoid bone in the wrist, a ganglian cyst, scapholunate dissociation, or a flexor tendon sheath infection. If initial x-rays are normal yet pain persists, your doctor may recommend a three-phase bone scan. In the meantime, he or she will fit you with a splint. The splint holds the wrist in a neutral position for three weeks, during which time you can monitor the injury for improvement or continuing pain. Over-the-counter or prescription medication may be recommended. NSAIDs (nonsteroidal anti-inflammatory drugs) are often used to limit discomfort. The aim of treatment is to limit the destruction of the wrist joint. Your doctor may recommend surgery in order to remove the injured bone and insert a replacement bone or prosthesis. Appropriate analgesia is used and outpatient pain medication is prescribed. Surgical risk increases with smoking and/or the use of drugs, including mind-altering drugs, muscle relaxants, antihypertensives, tranquilizers, sleep inducers, insulin, sedatives, beta-adrenergic blockers, and corticosteroids. Drink only water before manipulation or surgery. When it is possible to exercise the wrist with gentle, limited motion, your doctor will recommend specific rehabilitation exercises. He or she may advise you to treat the wrist with heat, using a heating pad, heat lamp, hot soaks, or whirlpool treatments. Ice massage is also recommended before and after exercising the wrist. You may be advised to tape your wrist to limit swelling. Keinböck's disease requires long-term management. You may have to alter your activities and occupation, depending on the degree of damage to the wrist. Early intervention is important for limiting progression of the disease to other bones in the wrist joint. The information provided herein is not intended to be a substitute for professional medical advice. You should not use this information to diagnose or treat a health problem or disease without consulting a licensed physician. ©2000 DynoMed.com, LLC, Indianapolis, IN |