Three proximal and 2 mid shaft recurrent radioulnar synostoses were managed with a “wrap around” vascularized muscle interposition after excision of the heterotopic bone. A proximally pedicled brachioradialis flap was used for the proximal forearm and elbow synostoses, and the flexor carpi ulnaris muscle was used for the midshaft area. Anatomy of the flaps and the technical details of each procedure are thoroughly described. After a mean follow-up period of 8 years (range 3–14 years), there were no recurrences. The functional outcome regarding forearm rotation, elbow motion, and working capacity was highly satisfactory in all 5 patients.