Proprioceptive deficits and postural instability in adolescent idiopathic scoliosis: a comparative study of balance control and key predictors

Background: Adolescent idiopathic scoliosis (AIS) is associated with postural instability, which may be influenced by proprioceptive deficits. While previous studies have examined balance impairments in scoliosis, the extent to which proprioception errors contribute to postural instability remains unclear. Understanding this relationship is crucial for developing targeted rehabilitation strategies. Objectives: This study aimed to assess proprioceptive accuracy and postural stability in individuals with AIS compared to healthy controls and identify key predictors of postural instability. Methods: This cross-sectional study included 60 participants (30 with AIS, 30 controls). Postural stability was assessed using the Biodex Balance System (BBS), measuring Overall Stability Index (OSI), Anterior-Posterior Stability Index (APSI), Medial-Lateral Stability Index (MLSI), Center of Pressure (COP) displacement, and Reaction Time. Lumbar proprioception errors in flexion and extension were evaluated using an inclinometer-based joint repositioning test. Results: The AIS group showed significantly greater COP displacement (p = 0.013) and lumbar proprioception errors in flexion (p = 0.021) and extension (p = 0.004) compared to controls. Regression analysis identified proprioception errors and COP displacement as significant predictors of postural instability (R² = 0.647). Conclusion: Individuals with scoliosis exhibit significant proprioceptive deficits, which strongly correlate with postural instability. These findings highlight the importance of proprioceptive training in scoliosis rehabilitation to improve balance control.