Ulnar nonunion after osteoclasis for rotational deformities of the forearm

PURPOSE: Osteoclasis, a minimally invasive technique to rotate the radius and ulna, is used commonly to correct forearm rotational deformities in children. The purpose of this investigation was to evaluate objectively osteotomy healing in patients treated with osteoclasis, with specific attention given to the risk for nonunion. METHODS: We identified 69 extremities in 65 children treated with osteoclasis and performed retrospective chart and radiographic reviews to evaluate the time to union of the radius and ulna and factors influencing healing. RESULTS: The average rotational correction was 90 degrees. Twenty-one ulnas had either delayed union or nonunion. Forty-eight of the forearms healed in less than 3 months. Factors correlated with a significantly decreased union rate included increased patient age, percutaneous technique, osteoclasis site in the proximal ulna, and primary diagnoses other than congenital radioulnar synostosis. Preoperative forearm position, magnitude of position correction, and treatment of the periosteum were not associated with changes in union rates. CONCLUSIONS: Forearm osteoclasis has a delayed union rate of 16%. Timely union of the ulna appears to be influenced by both patient-centered factors and surgical technique. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic, Level IV.