Congenital Humero-radio-ulnar Synostosis with Constriction Ring and Flexion Contracture of the Fingers: A Case Report

ABSTRACT Congenital humero-radio-ulnar synostosis (HRUS) is a rare malformation. Some cases are hereditary in origin and some are sporadic. We report on a sporadic case of HRUS.
A patient with HRUS is described who had constriction ring on the left upper limb and flexion contracture of the wrist joint and fingers. There was no range of motion nor crease at the elbow joint. Hypoesthesia was noted at the distal part of the ring of the upperarm as she did not respond to pin-prick. But circulatory failure like cyanosis or congestion was not seen on the extremity. No operation was performed to release the constrictive ring because it was not so deep. Only splint was applied to correct flexion contracture of the thumb, middle finger and ring finger. Three months later, examination of the thumb and fingers showed full extention. The sense to pain by pin-prick has been improved as the ring on the upperarm shallowed. A minor ischemic change may have been caused by the ring and followed by the contracture and the sensory disturbance. Synostosis also may have been related with the ring.