The lunate is the keystone of the wrist, and the primary pathological structure of Kienböck’s avascular necrosis. The normal lunate has a thin single layer of proximal subchondral bone plate, which is at risk of fracture, which does occur in Kienböck’s disease. There are spanning trabeculae between the proximal and thick distal subchondral bone plate. The Kienböck’s avascular necrosis “at-risk” wrist includes a radius with negative ulnar variance and flatter radial inclination. The lunate is small with a thin proximal cortex and is a Viegas type 1 and Zapico type 1 lunate.