Lunate avascular necrosis develops because of compromise to the blood supply to the lunate bone. Although a microfracture may be noted, a post-traumatic or overuse etiology is unusual; rather, the development of kienbock's disease is typically idiopathic.
Xrays are helpful in staging the severity of the involvement of the lunate, and are taken into consideration along with the length of the ulna bone, in order to select a surgical option to help take away pain and restore functional motion.

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