Kiënbock’s disease, which is also called avascular necrosis of the lunate, is a rare but potentially serious wrist disorder in which the blood supply to the lunate bone (one of the small carpal bones located in the wrist) is disrupted. The lunate bone works in conjunction with the forearm bones (ulna and radius) to allow proper movement of the wrist.
Because bone is living tissue which needs a regular supply of blood for nourishment, when the lunate does not receive adequate blood flow, the result can be osteonecrosis (bone death). In milder cases of Kiënbock’s disease, the lunate damage can cause pain, stiffness, and swelling. Kiënbock’s disease is most commonly seen in men ages 20-40 and usually affects only one wrist.
What are the symptoms of Kiënbock’s disease?
- Limited range of motion in the wrist
- Tenderness at the top of the hand, mid-wrist, over the lunate
- Difficulty and/or pain when the hand is turned upward
- Decreased grip strength in affected hand
- Clicking sound when moving the wrist
H2 What Causes Kiënbock’s Disease?
While the exact cause of Kiënbock’s disease is not fully known, it oftentimes presents after some type of trauma to the wrist, such as a fall. A patient may think the wrist injury is a sprain due to the pain and swelling that can occur, however the single event may have interrupted the blood flow to the lunate bone. Most researchers believe that multiple factors come into play which make a patient at higher risk for developing Kiënbock’s disease.
Possible contributors to Kiënbock’s disease include:
- Skeletal variations in the lunate bone
- Increased wrist pressure from a length difference between the ulna and radius
- Certain diseases, such as cerebral palsy, lupus, gout, and sickle cell anemia, that can affect blood supply
- Insufficient arterial blood supply due to having only one blood vessel rather than two supplying blood to the lunate
- Recurring microinjuries, such as those cause by repetitive motion
Stages of Kiënbock’s disease
The progression of Kiënbock’s disease varies on a case by case basis, however, it typically develops slowly over a period of time (which can be years) and progresses through four stages unless diagnosed and treated.
Stage 1: The blood supply to the lunate is inadequate, but damage may not yet appear on an x-ray. The wrist usually feels tender, as if sprained, with pain and possible swelling.
Stage 2: The lunate bone begins a hardening process (sclerosis) due to lack of blood supply. X-rays will show this bone density as whiter or brighter areas, indicating the bone is beginning to die. The wrist continues to be tender and painful with possible swelling.
Stage 3: The lunate bone dies and begins to break apart in fragments, which can result in the surrounding wrist bones shifting positions. Wrist pain typically increases, range of motion may become limited, and hand grip/strength may weaken.
Stage 4: The surrounding wrist bones deteriorate, which can cause arthritis that may be debilitating.
Some patients with Kiënbock’s disease have experienced a more rapid rate of progression through these stages, making early diagnosis and treatment more critical to preserve wrist functionality. Learn more about Diagnosing and Treating Kiënbock’s Disease.
Diagnosing Kiënbock’s Disease
Kiënbock’s disease can be difficult to diagnose, as x-rays usually do not reveal any damage this early. Since Kiënbock’s disease is a progressive process, many patients experience symptoms for months or even years before the symptoms are bothersome enough to seek medical treatment.
Magnetic resonance imaging (MRI) or a CT scan is often necessary to assess blood supply during the onset of Kiënbock’s disease. Early detection is key, however, in stopping its progression since bone damage cannot be reversed. Left untreated, Kiënbock’s disease can lead to severe pain, as well as loss of mobility in the wrist.
If you are experiencing wrist pain or swelling and/or other symptoms of Kiënbock’s disease, contact the orthopedic and hand specialists at OSMI Ft. Worth for an evaluation.
The Hand Therapy Center at the Orthopedic & Sports Medicine Institute (OSMI) in Fort Worth provides comprehensive hand physical therapy and rehabilitation services by our group of board-certified hand therapists (CHT) who treat a large variety of injuries and disabilities of the fingers, hand, arm and shoulder.
If you are ready to choose a team of hand, wrist and elbow orthopedic and sports medicine specialists that offer state-of-the-art treatment and highly personalized care, contact the OSMI office or call 817-529-1900 today!