Brain morphometric alterations associated with degenerative scoliosis: a structural MRI study.

BACKGROUND: Degenerative scoliosis (DS) is conventionally viewed as a localized spinal biomechanical failure. However, the resultant chronic postural asymmetry and prolonged nociceptive signaling strongly suggest involvement of the central nervous system. This study aimed to provide morphometric evidence for this central involvement by investigating cortical and subcortical structural differences between individuals with DS and healthy controls.

METHODS: Thirty-nine participants (19 DS patients, 20 controls) underwent high-resolution T1-weighted magnetic resonance images (MRI). Brain morphometry was assessed using the volBrain automated segmentation pipeline. Between-group comparisons were performed using ANCOVA (controlling for age and sex), and regularized regression models were applied to identify discriminative features.

RESULTS: DS patients exhibited widespread morphometric alterations compared to controls. The most pronounced changes were significant ventricular enlargement (Lateral Ventricle volume) and subcortical atrophy in the thalamus and cerebellum (p<0.001, large effect sizes). Additionally, selective volume reductions were observed in insular and precentral gyri. In an exploratory, leakage-free internal validation, a regularized machine-learning model discriminated DS from controls based on these neuroanatomical features (cross-validated ROC-AUC 0.96, 95% CI 0.91-0.99); given the small single-center sample, this finding is hypothesis-generating and requires external validation.

CONCLUSION: DS is associated with selective cortical and subcortical morphometric alterations primarily affecting the cerebellar-thalamo-cortical network. These findings likely reflect a combination of atrophic degeneration and structural adaptation to chronic postural imbalance. Our results underscore the central contribution to DS pathophysiology and warrant future longitudinal and multimodal MRI studies to clarify the temporal and functional significance of these changes.

STUDY DESIGN: Cross-sectional Study.