An unusual phenotype of radial longitudinal deficiency (radial hemimelia) presenting in a young adult male.

Radial longitudinal deficiency is a rare skeletal anomaly characterized by a defect in the development of structures that form the radial half of the forearm. The disorder is associated with a large spectrum of preaxial abnormalities. It is shown that the thumb and preaxial carpal bones are almost always hypoplastic or absent in almost all types of radial longitudinal deficiency. Congenital dislocation of the dysplastic radial head may accompany this rare deformity. Herein, we present a 20-year-old male patient with radial longitudinal deficiency who had a markedly hypoplastic radius but had a thumb and carpal bones with normal size, shape, and joint relations. Further, the right radial longitudinal deficiency of our patient was unusually accompanied by left congenital radial head dislocation. Our case shows that, although rare, radial longitudinal deficiency can present without any carpal and thumb abnormalities. And the current case also shows that a contralateral sided congenital radial head dislocation may accompany radial longitudinal deficiency.