Nusinersen administration in spinal muscular atrophy patients with severe scoliosis: Interlaminar approaches at the lumbar level

Abstract

Purpose: Spinal muscular atrophy (SMA) is a genetic progressive neuromuscular disorder, and nusinersen has shown to improve its symptoms. Scoliosis is a frequent symptom in patients with SMA and complicates the intrathecal injection of nusinersen. The aim of this study was to inves-tigate the safety and effectiveness of fluoroscopy-guided intrathecal injections in patients with SMA with severe scoliosis. Methods: We retrospectively reviewed the medical records of 11 patients with SMA treated with nusinersen intrathecal injections at the Samsung Medical Center from 2018 to 2020. We as-sessed the type of SMA, genetic results, spine computed tomography or fluoroscopy findings, and adverse effects associated with the injection. Results: Of 11 patients with SMA, six were diagnosed with severe scoliosis, four of whom underwent an operation for scoliosis. The six patients with severe scoliosis started receiving the nusin-ersen injection at a median age of 15.7 years. A total of 25 injections were completely performed with the interlaminar approach (ILA) at the lumbar level under C-arm fluoroscopy guidance. No adverse effects other than mild headache occurred. In one patient who underwent the complete fusion operation for scoliosis, laminectomy was performed for the nusinersen injection, and 3 doses were administered intrathecally via the interlaminar route at the lumbar level. Conclusion: Fluoroscopy-guided ILA is a safe method for the intrathecal injection of nusinersen in patients with SMA with severe scoliosis. When defining the route, laminectomy might be nec-essary to open the window for the ILA route at the lumbar level.