Kienböck's disease is a disorder of the wrist. It is named for Dr. Robert Kienböck, a radiologist in Vienna, Austria who described osteomalacia of the lunate in 1910.Left hand x-ray with Kienbock's Disease showing 4 mm negative ulnar variance and Kienbock's Disease Stage IIIBLeft hand x-ray with Kienbock's DiseaseLeft hand x-ray post proximal row carpectomy Kienböck's disease is a disorder of the wrist. It is named for Dr. Robert Kienböck, a radiologist in Vienna, Austria who described osteomalacia of the lunate in 1910. It is breakdown of the lunate bone, a carpal bone in the wrist that articulates with the radius in the forearm. Specifically, Kienböck's disease is another name for avascular necrosis (death and fracture of bone tissue due to interruption of blood supply) with fragmentation and collapse of the lunate. This has classically been attributed to arterial disruption, but may also occur after events that produce venous congestion with elevated interosseous pressure. The exact cause of Kienböck's is not known, though there are thought to be a number of factors predisposing a person to Kienböck's. Although there is no evidence that Kienböck's disease is inherited, it is possible that unidentified genetic factors could contribute to the development of the condition. Recent studies have made a correlation between Kienböck's sufferers and Western European ancestry, but no definitive link can be positively confirmed. The necrosis of the lunate bone can frequently be traced to a trauma to the wrist, like a compound fracture, which could cause the lunate's blood supply to be interrupted. Blood flows to the lunate through several arteries, each supplying a percentage. When one of these pathways is severed, the likelihood the patient will develop necrosis increases.Despite a preponderance of evidence, no particular cause has been conclusively verified. Data exists on the internet that most people suffering from Kienböck's are affected in their dominant hand, though about one-third of sufferers report the condition in their non-dominant hand. In very few cases have there been people that have acquired it in both wrists. Kienböck's disease is classified as a 'rare disorder,' meaning that it affects fewer than 200,000 people in the U.S. population. Many Kienböck's patients are frustrated by the lack of consensus among hand surgeons about optimal treatments for Kienböck's. No matter what the disease's stage of progression, there is no one best treatment, and the decision is often based partially, or even mostly, on incidental factors such as the patient's pain tolerance, the patient's desire to return to active use of the hand (such as in manual occupations), and the surgeon's level of expertise with different treatments.