An unusual association of ulnar hemimelia with mesoaxial synostotic syndactyly.

Ulnar hemimelia, also referred to as post-axial longitudinal deficiency of the upper limb, is a very rare skeletal anomaly characterized by the partial or complete absence of the ulna. The majority of the reported cases are sporadic and more common in males. The disorder is mostly unilateral, right-sided and incomplete. A slight shortening of the forearm, radial bowing and ulnar-sided hand drift are the anomalies which often accompany ulnar hemimelia. Ulnar hemimelia may also be seen in association with complex wrist and hand anomalies. The absence of post-axial metacarpal and digital bones are frequent findings in patients with this rare disorder. Cases with additional digital abnormalities such as post-axial syndactyly and camptodactyly are also present in the literature. However, a case of ulnar hemimelia in association with mesoaxial synostotic syndactyly has never been reported to date.