Congenital radio-ulnar synostosis.

Thirty-three patients with congenital radio-ulnar synostosis were examined. There was one familial predisposition. Chromosomal patterns were examined in seventeen patients and were normal. Bone maturation appeared normal. The radial deviation angle, in the patients whose distal radial epiphysis had closed, was elevated (Madelung's deformity). However, in the patients whose distal epiphysis maturation score was 8, it was not elevated. On the other hand, elongation of the ulna (plus variant) and/or dorsal dislocation of the distal end of the ulna was seen in early life. In terms of treatment, all attempts to divide the two bones failed. It was found that derotation of the nonwriting hand by an osteotomy through the proximal fusion mass was a useful procedure.