We reported two cases of subcataneous extensor tendon rupture in the finger secondary to kienböck's desease, and studied the anatomic relationship of the lunate and extensor tendons.
The two patients were sixty-three-years old and forty-five-years old respectively. Radiographs showed stage IV kienböck desease by Takada's classification. Both ruptures occured in the ring finger.
In thirty hands in fifteen cadavers the middle and ring extensor tendons were on the lunate in a high percentage, and the tendency to rupture the tendons in chinical cases was associated with this anotomic relationship.
