Preceding neurosurgery is not needed for presumed adolescent idiopathic scoliosis with syringomyelia: a 10-year longitudinal comparative study

Background: One-stage scoliosis correction surgery is safe for adolescent idiopathic scoliosis (AIS), but it is not yet known whether it is safe for presumed AIS (PAIS). This study sought to investigate the safety and efficacy of one-stage scoliosis correction surgery for PAIS associated with syringomyelia from multiple perspectives by conducting an analysis of 10-year consecutive cases.Methods: A retrospective study of all consecutive cases of patients diagnosed with PAIS associated with syringomyelia or AIS from January 2011 to January 2020 was performed. The main radiographic parameters and clinical function scores before, immediately after, and at the last follow-up were collected or measured. Three-dimensional (3D) models of spinal canal length were generated, refined, measured, and compared between the PAIS and AIS groups.Results: In total, 318 patients with AIS and 47 patients with PAIS associated with syringomyelia were included in the study. There were no significant differences between the two groups in terms of changes in the Cobb angle of the main curve (MC), thoracic kyphosis (TK), coronal balance (CB), sagittal vertical axis (SVA), Oswestry disability index (ODI), Scoliosis Research Society-22 (SRS-22) score, cervical and thoracolumbar spinal canal length, and whole spinal canal length before and after the surgery (P>0.05). The changes in the thoracolumbar and whole spinal canal length were significantly positively correlated with the improvement rate of the MC (P<0.05), but were not significantly correlated with the improvement rate of TK, the SRS-22 score, and the ODI (P>0.05).Conclusions: In relation to the main radiologic parameters, clinical function scores, and 3D biomechanics, one-stage posterior correction surgery was found to be safe and effective for patients with PAIS associated with syringomyelia.