The recognition of carpal instability as a clinical entity is relatively recent. The relationship between Kienböck's disease and volarflexed intercalated segment instability of the wrist is a matter of controversy.
In the wrists of thirty-one patients with Kienböck's disease, fourteen patients treated surgically by means of shortening of the radius and seventeen patients treated conservatively, a roentgenographic analysis was carried out. Carpal height ratio, carpal ulnar distance ratio, Stahl's index, capitolunate angle, radiolunate angle, radioscaphoid angle and scapholunate angle were measured.
From these studies, it was concluded that the collapse of the lunate allows proximal migration of the capitate and volarflexed intercalated segment instability pattern (VISI pattern), and that shortening of the radius can be considered to be an effective treatment of Kienböck's disease.
