Manual therapy promotes prefrontal neural efficiency in chronic non-specific neck pain: An fNIRS-Based randomized controlled trial.

Abstract

Background Chronic non-specific neck pain (CNP) involves central sensitization and maladaptive cortical reorganization. The central neurophysiological mechanisms underlying combined manual therapy (MT) and exercise remain poorly understood. Objective To investigate the neurobiological synergy of MT and exercise on large-scale brain network restructuring and cortical adaptation in patients with CNP. Methods Thirty patients with CNP were randomized to 6 weeks of MT plus exercise (combined group, n = 15) or exercise alone (n = 15), alongside 15 healthy controls. Clinical outcomes included the Visual Analogue Scale (VAS) and Neck Disability Index. Functional near-infrared spectroscopy (fNIRS) evaluated resting-state functional connectivity and task-state cortical hemodynamics. Results Both groups demonstrated significant longitudinal improvements in pain and disability (e.g., VAS main time effect: F = 279.51, P p 2 = 0.909, 95% confidence interval [2.50, 3.19]), with no significant group-by-time clinical interaction. However, neurobiological trajectories dissociated markedly. Only the combined intervention uniquely restored frontoparietal functional connectivity and induced a stimulation-preferential reduction in prefrontal activation (interaction: F = 27.19, P p 2 = 0.493). Conclusions While MT combined with exercise yields similar short-term clinical benefits as exercise alone, the combined therapy uniquely promotes prefrontal neural efficiency and restores frontoparietal network connectivity. This highlights MT's distinct central modulatory value in optimizing top-down cognitive resource allocation for CNP management.