Résumé : A 22-year-old patient with type I trichorinophalangeal Langer-Giedion syndrome presented a stage 2 osteonecrosis of the lunate associated with congenital shortening of the ulna and carpal tunnel syndrome. The patient was treated by shortening osteotomy of the radius and median nerve neurolysis, with an excellent result. This case provides an additional piece of evidence associating ulnar-minus variance with lunatomalacia, and another argument in favor of the theory that Kienbock's disease results from microfractures sustained by the lunate under an abnormal stress distribution situation.