[Ulnar dimelia: imaging modalities and surgical implications]

To report 2patients with ulnar dimelia.

Plain radiographs (2patients), angiography (1patient), MR (2patients), CT (2patients) with 3Dreconstruction (1patient) were performed.

Unilateral polydactyly with absence of the thumb, ulnar duplication with absence of radius were observed in both patients. Shoulder dislocation was present in one patient. Vascular anomalities were observed in one patient who underwent angiography but did not interfere with polydactyly surgical treatment and pollicisation. CT with 3D helped in delineating the elbow and shoulder bone abnormalities and thus in planning elbow osteotomies. MR was helpful in imaging muscle anatomy.

Ulnar dimelia or "mirror hand" is a rare congenital disorder of the upper limb. Approximately 70cases have been reported, including 3 with shoulder dislocation. A multimodality imaging approach, exploring the various aspects of the malformation is mandatory to help the surgeon in order to obtain a functional and aesthetic upper limb after complex surgical procedures taking into account the various aspects of the malformation.