Background: The present study was carried out to answer three questions: 1) How much forearm rotation can be expected after mobilization of congenital radioulnar synostosis (CRUS)? 2) Does preoperative radius head dislocation affect forearm rotation after mobilization? 3) What factors other than radius head dislocation affect postoperative forearm rotation?
Methods: We performed mobilization of CRUS with a free vascularized fascio-fat graft and a radius osteotomy (Kanaya's procedure) on 26 forearms of 25 patients. The age at the surgery ranged from 5.3 to 13.