Kienböck's disease is a condition where the lunate bone in the wrist loses its blood supply, leading to bone death and joint pain.
The lunate is one of the small bones that make up the wrist, sitting centrally and bearing a significant share of the load transmitted through the joint. Kienböck's disease occurs when the blood supply to the lunate is disrupted, leading to avascular necrosis, a gradual death of bone tissue from lack of blood flow.
The condition is progressive, and is generally described in stages, from early changes visible only on MRI, through to collapse of the bone shape and, eventually, wider wrist arthritis if left untreated. The stage at diagnosis strongly influences which treatments are appropriate.
The exact cause of Kienböck's disease is often not identified. It is associated with variations in the relative length of the two forearm bones, particularly where the ulna is shorter than usual relative to the radius, which appears to place more load through the lunate. Repetitive loading of the wrist and, in some cases, a previous wrist injury are also recognised contributing factors.
It most often affects young to middle-aged adults, and manual occupations involving repetitive wrist loading may be associated with a higher likelihood of developing symptoms.
Typical symptoms of Kienböck's disease include:
Because early symptoms can be mild and non-specific, the condition is sometimes diagnosed later than ideal, which is one reason persistent, unexplained wrist pain deserves proper investigation.
Diagnosis is confirmed with imaging, usually an MRI, which can detect changes in the lunate before they are visible on a plain X-ray, together with X-rays to assess bone shape and staging.
Early-stage disease may be managed with splinting, activity modification and anti-inflammatory medication, aiming to reduce load through the lunate while symptoms are monitored.
Surgical options depend on the stage of disease and may include procedures designed to reduce load on the lunate, such as shortening the radius bone, or procedures to try to restore blood supply to the bone. For more advanced disease where the lunate has collapsed, salvage procedures such as proximal row carpectomy or a partial wrist fusion may be considered to relieve pain and preserve as much function as possible.
The outlook varies considerably depending on the stage at which the condition is diagnosed and treated. Earlier-stage disease treated promptly has a better chance of halting progression and preserving wrist function. More advanced disease, with collapse of the bone or wider arthritis, is more challenging to treat and may need more involved reconstructive or salvage surgery, though pain relief and improved function can still generally be achieved.
Kienböck's disease is an uncommon but important cause of wrist pain, where the lunate bone gradually loses its blood supply. Treatment aims to relieve pain and, where possible, halt progression, with the specific approach depending heavily on how advanced the condition is at diagnosis. Persistent wrist pain and stiffness without an obvious cause is worth investigating, given how much earlier assessment can influence the range of treatment options available.
