[Etiology, diagnostics and classification of lunate bone necrosis].

Kienböck's disease, also known as avascular necrosis of the lunate bone describes the slowly progressive osteonecrosis of the lunate bone with secondary development of osteoarthritis and carpal collapse. In order to emphasize the atraumatic origin of the disease, this is normally referred to as aseptic, idiopathic or avascular lunate necrosis. There are thought to be a number of factors predisposing to Kienböck's disease, such as ulnar negative variance, the shape of the lunate itself and various types of vascular anatomy. The ongoing development of radiographic techniques in recent years has contributed to a better understanding of the progression of the disease and led to a modification of the standard classifications. New sophisticated classification methods provide the basis for a differentiated treatment. This article provides an overview of the current state of knowledge about the etiology and pathogenesis as well as the clinically relevant diagnostic procedures and classifications.