Neuromorphological Alterations in the Somatosensory System of Adolescent Idiopathic Scoliosis: A Systematic Review of Magnetic Resonance Imaging Studies

BACKGROUND/OBJECTIVES: This systematic review synthesizes MRI evidence to characterize neuromorphological alterations in somatosensory and vestibular brain regions among adolescents with idiopathic scoliosis (AIS). METHODS: This systematic review was conducted in accordance with the PRISMA 2020 guidelines. We systematically searched five databases from inception to January 2026 for case-control MRI studies comparing AIS patients (10-18 years) with healthy controls. Two reviewers independently screened studies, extracted data, and assessed the risk of bias using the Newcastle-Ottawa Scale. RESULTS: Across 15 studies (1270 participants), AIS patients demonstrated consistent neuromorphological alterations: (1) lower cerebellar tonsil position (0.9-2.8 mm below baseline), with ectopia incidence correlating with curve severity; (2) cortical thickening in bilateral medial regions but thinning in left paracentral areas; (3) left-dominant white matter volume increases and impaired microstructure in the corpus callosum; and (4) left-sided vestibular morphological changes, including a more vertical semicircular canal. CONCLUSIONS: AIS is associated with consistent neuromorphological alterations in key somatosensory and vestibular regions, supporting a potential neuroanatomical basis for impaired sensorimotor integration in its pathogenesis. It should be noted that substantial heterogeneity among the included studies prevented a meta-analysis, and the cross-sectional design limits causal interpretations Registration: This systematic review was registered in PROSPERO (CRD42024577195).