Successful use of posterior instrumented spinal fusion alone for scoliosis in 19 patients with neurofibromatosis type-1 followed up for at least 25 months

Abstract

Posterior instrumented fusion alone has been considered inadequate to correct scoliosis in most patients with neurofibromatosis type-1 (NF-1) because of their weak bone structure. This study was undertaken to evaluate whether the extension of fusion one level beyond the conventional fusion level would enable posterior instrumented fusion alone to be as effective as anterior-posterior fusion in treating patients with NF-1 and scoliosis who are more than 10 years old and whose scoliosis is <90 degrees . Nineteen patients with NF-1 were treated surgically with long, posterior instrumented fusion for scoliosis from 1998 to 2004. Among the patients, 3 had nondystrophic curves, and 16 had dystrophic curves. Posterior fusions were performed that used abundant bone grafts, and included neutral and stable vertebrae in both the coronal and sagittal planes and any coronal curves of more than 40 degrees . The mean coronal and sagittal Cobb's angles in the nondystrophic curves were 79 degrees and 16 degrees before surgery, 31 degrees and 12 degrees after surgery, and 37 degrees and 15 degrees at follow-up, respectively. In the dystrophic thoracic curves, the Cobb's angles in the coronal and sagittal planes before and after surgery and at follow-up were 68 degrees and 31 degrees , 27 degrees and 28 degrees , and 33 degrees and 30 degrees , respectively. There were no cases of coronal or sagittal decompensation, neurologic complications, or infections. There were eight (42.1%) complications, three intraoperative and five late. Pseudarthrosis with instrumentation failure that required revision surgery occurred in one (5.2%) patient. These results demonstrate that a satisfactory stabilization of scoliosis can be achieved by posterior fusion with instrumentation alone in patients with NF-1 who are more than 10 years old, and whose scoliosis is <90 degrees .