Kienböck's disease: two unusual cases.

Two unusual cases of Kienböck's disease are reported. The first is of a young woman whose presenting feature was spontaneous rupture of the flexor pollicis longus tendon. This is the first reported case in which such a rupture was the presenting feature of the condition. The second is of a 71-year-old woman with scleroderma and Raynaud's disease who did not develop her Kienböck's disease until late in life. The literature contains no older patient with this condition and a likely association is made between the avascular necrosis and the vasculitis associated with this connective tissue disorder.