Dynamic Neuromuscular Stabilization for Midlife Women with Frozen Shoulder: Clinical Effects on COP and Pain

Objectives: Frozen shoulder (FS) leads to pain, reduced shoulder function, and deficits in postural stability and sensorimotor control during upper-limb weight-bearing and activities of daily living tasks. This study investigated how an eight-week Dynamic Neuromuscular Stabilization (DNS) program affected Center of Pressure (COP) control and pain in midlife women with FS. Methods: Twenty-two midlife women with FS were randomly assigned to a DNS group (DNSG, n = 11) or a control group (CG, n = 11). The DNSG performed DNS exercises twice weekly for eight weeks, while the CG performed a dynamic stretching-based active control program. COP variables (distance, velocity, and root mean square (RMS) in the anterior-posterior (AP) and medial-lateral (ML) directions) were measured using a force platform under affected-side single-hand support with visual input and bilateral hand support with and without visual input. Pain was assessed using the Visual Analog Scale (VAS). All variables were analyzed using a two-way mixed ANOVA. Results: Under the affected-side single-hand support condition, a significant group × time interaction was observed for the prespecified primary outcome, ML-RMS (p < 0.05). Other COP variables under this condition were not significant after Holm-Bonferroni correction. Under bilateral hand-support conditions, ML-RMS remained significant after multiplicity adjustment in both visual conditions (p < 0.05). Pain (VAS) decreased over time in both groups, with no significant group × time interaction observed. Conclusions: The DNS intervention was associated with positive changes in COP-based postural control during upper-limb weight-bearing tasks in midlife women with FS. Pain decreased over time in both groups, with no significant group-by-time interaction. These findings suggest that DNS may be a potentially useful intervention for improving postural stability during upper-limb support tasks in patients with FS.