Avascular necrosis – lunate

AVN in lunate. There is diffuse sclerosis of the lunate bone (arrow) in this patient’s wrist, characteristic of avascular necrosis. This is also known as Kienbock’s disease. It can develop after trauma but often there is no history of a precipitating event. As it progresses, the lunate may collapse and fragment, which predisposes to early osteoarthritis of the wrist.