Neurofibromatosis: Etiology, Commonly Encountered Spinal Deformities, Common Complications and Pitfalls of Surgical Treatment

Neurofibromatosis 1 (NF-1) is a multisystemic, autosomal dominant genetic disorder. Skeletal complications usually present early in life and can be attributed to abnormalities of bone growth, remodeling, and repair, or can be secondary to nearby soft-tissue abnormalities complicating NF-1. Skeletal complications can be categorized as generalized or focal manifestations. The incidence of spinal deformities in association with NF-1 varies from 2% to 36%, with scoliosis being the most common. Both heritable and nonheritable factors contribute to the pathogenesis of spinal deformities in NF-1 patients. Traditionally, the spinal deformities are classified into dystrophic or nondystrophic. The pathophysiology of dystrophic curves is still uncertain, but may require a nonhereditary event, such as an adjacent tumor or a second hit event in local bone cells, leading to the underlying dysplasia. Dystrophic curves may result in scoliosis, kyphosis, or frequently, kyphoscoliosis. The goal of surgical management is to arrest the progression of deformity instead of achieving complete correction. The current state-of-the-art treatment for significant deformity is combined anterior and posterior spinal arthrodesis. Postoperative orthotic immobilization is almost always recommended in an effort to prevent pseudoarthrosis. The orthosis should be maintained until a fusion mass is obtained. Assessment of the fusion mass by computed tomography (CT) or magnetic resonance imaging (MRI) should be performed. Major complications, such as paraplegia, pseudoarthrosis, intraoperative hemorrhage, and postoperative progression of the deformity may occur. In an attempt to eliminate complications and achieve the best results, a multidisciplinary treatment strategy is needed. The intent of this article is to present the spinal deformities that are most commonly associated with NF-1, to identify the underlying biology of spinal deformities based on the most recent literature, and to address the common complications and pitfalls of their surgical management. © 2012 Scoliosis Research Society