Effects of the Timing of Vagus Nerve Stimulation Combined With Exercise in Chronic Neck Pain

Chronic neck pain is a common musculoskeletal condition associated with pain, functionallimitations, sleep disturbances, and alterations in autonomic nervous system activity.Exercise therapy is one of the main conservative treatment approaches for chronic neckpain. Transcutaneous auricular vagus nerve stimulation (taVNS) is a non‐invasiveneuromodulation method that aims to stimulate the auricular branch of the vagus nerve andmay influence parasympathetic activity and pain modulation.The purpose of this randomized controlled trial is to investigate whether the timing oftaVNS relative to exercise influences clinical and physiological outcomes in individualswith chronic neck pain.A total of 81 participants with chronic neck pain will be randomly allocated to threeparallel groups. Participants in the first group will receive taVNS before performing astandardized exercise program. Participants in the second group will perform the sameexercise program followed by taVNS. Participants in the control group will receive theexercise program alone.The exercise program will include postural correction exercises, deep cervical flexoractivation exercises, cervical mobility exercises, scapular stabilization exercises, andstretching exercises. The intervention period will last approximately 6‐8 weeks.Participants will be evaluated before and after the intervention period. Pain intensitywill be assessed using the Numeric Pain Rating Scale, neck‐related disability using theNeck Disability Index, sleep quality using the Pittsburgh Sleep Quality Index, andautonomic nervous system activity using heart rate variability, particularly the rootmean square of successive differences (RMSSD). Exercise adherence and session attendancewill also be recorded.The study will compare changes in these outcomes among the three groups to determinewhether the timing of taVNS relative to exercise influences the effectiveness ofrehabilitation in individuals with chronic neck pain.