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

Introduction

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°.

Methods

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°.

Results

The mean coronal and sagittal Cobb’s angles in the nondystrophic curves were 79° and 16° before surgery, 31° and 12° after surgery, and 37° and 15° 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° and 31°, 27° and 28°, and 33°and 30°, 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.

Conclusions

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°.