Transcutaneous Auricular Vagus Nerve Stimulation (taVNS) for the Treatment of Chronic Musculoskeletal (MSK) Pain in Adults With Cerebral Palsy

Chronic musculoskeletal pain is highly prevalent among adults with cerebral palsy (CP) and represents a major contributor to disability, reduced quality of life, and psychological distress. Pain in CP is often persistent, multifactorial, and inadequately controlled with available pharmacologic and rehabilitative treatments. Emerging evidence suggests that chronic low-grade inflammation, altered autonomic regulation, and disrupted central pain modulation may contribute to pain persistence in this population.

The vagus nerve plays a key role in regulating descending inhibitory pain pathways and inflammation via the inflammatory reflex. Reduced vagal tone has been associated with chronic pain and mood disturbances, suggesting that interventions targeting vagal activity may offer therapeutic benefit. Transcutaneous auricular vagus nerve stimulation (taVNS) is a noninvasive neuromodulation technique that activates vagal afferent fibers via the external ear and has demonstrated safety and feasibility across multiple clinical populations.

This single-site, randomized, double-blind, sham-controlled clinical trial will enroll adults with CP and chronic musculoskeletal pain. Participants will be randomized in a 1:1 ratio to receive either active taVNS targeting the auricular branch of the vagus nerve or sham stimulation delivered to the earlobe. The intervention will consist of a 30-day home-based stimulation protocol. Outcomes will be assessed at baseline and immediately following the intervention period.

The primary outcomes of this study are changes in musculoskeletal pain severity and pain-related interference with daily activities, as well as safety as assessed by treatment-emergent adverse events. Secondary and exploratory outcomes include measures of health-related quality of life, mood, fatigue, spasticity, autonomic function assessed via heart rate variability, and systemic inflammatory biomarkers. Findings from this trial will inform the therapeutic potential of taVNS for chronic pain in adults with CP and support the design of future definitive randomized controlled trials.