THREADED STEINMANN PIN FUSION OF THE CRANIOVERTEBRAL JUNCTION

Study Design. In a clinical retrospective study, the authors review lo ng-term results of occipitocervical fusion using a wide diameter, cont oured, threaded Steinmann pin. Objectives. To evaluate the clinical an d radiographic results of occipitocervical fusion using this technique in a variety of abnormalities including rheumatoid arthritis. Summary of Background Data. The various surgical techniques and hardware deve loped for occipitocervical fusion have been associated with mixed resu lts, particularly in patients with rheumatoid arthritis or basilar inv agination. Methods. Thirty-nine patients with occipitocervical instabi lity were internally fixed with a wide diameter, contoured, threaded S teinmann pin wired to the occiput and cervical laminae or facets. Fusi on was facilitated using autologous iliac crest bone graft and a cervi cal orthosis. Instability resulted from rheumatoid arthritis (n = 12), congenital anomalies (n = 12), trauma (n = 10), tumor (n = 4), or ost eogenesis imperfecta (n = 1). Fifteen patients had radiographic eviden ce of basilar invagination. Long-term outcome (mean follow-up period, 38.9 months; range, 12-78 months) was based on clinical and radiograph ic review. Results. Thirty-seven patients (97%) had a stable postopera tive occipitocervical construct: there were 35 osseous unions, two fib rous unions, and one nonunion. There was one postoperative death from pulmonary complications. No patient developed evidence of new, recurre nt, or progressive basilar invagination. Conclusion. The authors concl uded that rigid segmental fixation of the craniovertebral junction usi ng a wide diameter, contoured, threaded Steinmann pin and supplemental autograft creates excellent fusion with minimal complications. This t echnique is appropriate for a variety of abnormalities including rheum atoid arthritis.