DETERIORATION OF OPERATIVE CORRECTION IN DYSTROPHIC SPINAL NEUROFIBROMATOSIS

Study Design. Of 28 patients with dystrophic spinal deformity resultin g from neurofibromatosis who were treated surgically since 1968, 25 we re studied regarding the outcome of spinal deformity at a mean follow- up of 9.7 years after surgery (mean age at follow-up, 21.5 years). Obj ectives. This study sought factors that contribute to curve deteriorat ion despite successful spinal fusion for dystrophic spinal deformity i n patients with neurofibromatosis. Summary of Background Data/Methods. All patients had the following radiographs: standing anteroposterior and lateral, lateral bending, flexion and extension views of the spine , and radiographs of both tibiae. Patients who had large peripheral ne urofibromata or evidence of long-bone deformity at other sites had rad iographs of these anatomic regions. Spinal radiographs obtained pre-op eratively, 6-12 months post-operatively, and at final follow-up were m easured for spinal curvatures, vertebral height, and vertebral and dis c wedging. Results. For analysis, the patients were divided into three groups according to deformity: 1) scoliosis, 2) ky-phoscoliosis (with kyphosis >50-degrees) and 3) hyperkyphosis (with kyphosis >50-degrees and sharply angulated over three vertebrae). Mean deterioration was: scoliotic group, 12-degrees (range, 0-degrees-52-degrees); kyphoscolio tic group, 7-degrees (range, 0-degrees-35-degrees); hyperkyphosis grou p, 38-degrees (range, 20-degrees-60-degrees). All patients in the latt er group had anterior and posterior spinal fusion. Conclusion. Spinal deformity in these patients tended to progress despite the achievement of spine arthrodesis in those with hyperkyphosis and short curves. Th e study shows that vertebral subluxation, disc wedging, and peripheral skeletal dystrophy are additional prognostic features that predict th e progression of deformity after arthrodesis of the spine.