Intra-articular radial head fracture in the skeletally immature patient: progressive radial head subluxation and rapid radiocapitellar degeneration.

BACKGROUND: Intra-articular fractures of the radial head in skeletally immature patients are rare. Most studies in the literature group intra-articular radial head fractures with the more common extra-articular, metaphyseal fractures of the radial neck; considered as a group, outcomes are favorable. In this study, we specifically evaluate a group of skeletally immature patients with intra-articular radial head fractures, and a rapid progression of posterior subluxation of the radial head with the development of joint arthrosis.

METHODS: A chart review identified 7 patients who were referred for management of an intra-articular radial head fracture that had failed initial nonoperative management. All the elbows progressed to posterior radiocapitellar subluxation and joint degeneration within 4 months after initial injury. We cataloged clinical, radiographic, and intraoperative findings.

RESULTS: The average age at the time of injury was 10 years and 6 months (range, 8 to 13 y). Five patients were male and 2 were female. Five patients had Salter-Harris III fractures of the radial epiphysis, while 2 had Salter-Harris IV injuries. The radiocapitellar articulation was reduced on the initial injury films, but all the elbows showed progressive radiocapitellar subluxation and arthrosis, whereas the ulnohumeral articulation remained unaffected. Motion was decreased in all patients with an average arc of extension-flexion of 38 degrees to 127 degrees and an average arc of rotation of 84 degrees. Six patients underwent salvage surgery.

CONCLUSIONS: Skeletally immature patients with an intra-articular radial head fracture are at risk for progressive radial head subluxation and radiocapitellar arthrosis.

LEVEL OF EVIDENCE: Retrospective Case Series, Level IV.