Effects of proprioceptive neuromuscular facilitation training on shoulder proprioception and postural control in adolescents with idiopathic scoliosis: a randomized controlled trial

Proprioceptive deficits and impaired scapular control are increasingly recognized in adolescents with idiopathic scoliosis (AIS), yet whether targeted sensorimotor interventions provide benefits beyond conventional rehabilitation remains unclear. This study aimed to evaluate the additional effects of proprioceptive neuromuscular facilitation (PNF) on shoulder proprioception, scapular control, and global functional outcomes in AIS. In this assessor-blinded randomized controlled trial, 46 adolescents with AIS were randomly allocated to the PNF plus conventional rehabilitation group or the conventional rehabilitation group. Outcome assessments were conducted at baseline and after an 8-week intervention. Thirty-seven participants (PNF group, n = 19; control group, n = 18) completed the 8-week intervention and post-intervention assessments and were included in the per-protocol analysis. Primary outcomes included shoulder joint position sense assessed by the active reposition test (ART) and scapular postural control measured by scapular balance angle (SBA). Secondary outcomes included lateral scapular slide test (LSST), surface electromyography (sEMG), postural parameters, angle of trunk rotation (ATR), and health-related quality of life (SC-SRS-22). Between-group and within-group differences were analyzed using parametric or non-parametric tests according to data distribution. Both groups demonstrated improvements in selected postural and functional parameters after intervention. However, the PNF group showed significantly greater improvements in ART at medium and high target angles compared with the control group ( p < 0.05), along with superior reductions in SBA and LSST (0° position). Significant normalization of sEMG-based muscle activation symmetry was observed in the upper trapezius, lower trapezius, and infraspinatus muscles in the PNF group. In contrast, no between-group differences were found in ATR or SC-SRS-22 scores. Notably, improvements in scapular alignment and trunk rotation were not accompanied by parallel recovery of proprioception in the control group, indicating a dissociation between structural and sensorimotor adaptations. PNF provides additional benefits in shoulder proprioception and scapular neuromuscular control beyond conventional rehabilitation in AIS. However, these improvements do not translate into short-term changes in trunk rotation or health-related quality of life. These findings suggest that scapular proprioception represents a distinct, modifiable neuromuscular domain in AIS that may require targeted intervention independent of global postural correction. ChiCTR2500099252, Date: 2025-03-20.