Surgical Outcomes and Complications Following All Posterior Approach for Spinal Deformity Associated with Neurofibromatosis Type-1

Objectives : The purpose of this study was to evaluate surgical outcomes and complications of spinal deformity associated with neurofibromatosis type-1 (NF-1). Methods : From 2012 to 2018, patients suffering from spinal deformity associated with NF-1 who underwent surgical correction were identified. Demographic data and radiographic measures were retrospectively reviewed. Pre-and postoperative whole spine radiograph images were used to determine both coronal and sagittal Cobb angles. All of patients underwent 3-dimentional computed tomographic scan and magnetic resonance imaging scan to confirm dystrophic features. For evaluation of clinical outcomes, we surveyed the pre-and postoperative scoliosis research society-22r (SRS-22r) score. Results : Seven patients with spinal deformity associated with NF-1 were enrolled in this study. The mean age of patients was 29.5 +/- 1.2 years old. The mean follow-up period was 2.8 +/- 1.4 years. The apex of the deformity was located in cervicothoracic (n=1), thoracic (n=4), and lumbar region (n=2). Most patients have poor bone quality and decreased bone mineral density with average T-score of-3.5 +/- 1.0. All patients underwent surgical correction via posterior approach. The pre-and postoperative mean coronal and sagittal Cobb angle was 61.6 +/- 22.6 degrees and 34.6 +/- 38.1 degrees, 56.8 +/- 18.5 degrees and 40.2 +/- 9.1 degrees, respectively. Mean correction rate of coronal and sagittal angle was 44.7% and 23.1%. Ultimate follow-up SRS-22r score (average score, 3.9 +/- 0.4) improved comparing to preoperative score (average score, 3.3 +/- 0.9). Only one patient received revision surgery due to rod fracture. No serious complication occurred, such as neurological deficit, and viscerovascular injury. Conclusion : The surgical correction of patients having spinal deformity associated with NF-1 is challenging, however the radiographic and clinical outcomes are satisfactory. The all posterior approach can be a safe and effective surgical option for patients having dystrophic curves associated with NF-1.