Effect of RUSI-based core stability exercise on chronic non-specific low back pain patients: study protocol for a randomised controlled trial

INTRODUCTION: Low back pain (LBP) is one of the most highly prevalent pain both in developed countries and low-income and middle-income countries. Despite increasing healthcare resources and numerous treatment methods for LBP, the efficacy of these therapeutic strategies is still uncertain. Recently, core stability exercise (CSE) is popularly applied as a preventive or rehabilitative method in the treatment of LBP. However, the adequate activation of the local muscle systems of CSE needs further optimisation and quantification. This trial aims to investigate the feasibility and efficacy of CSE monitored by real-time ultrasound image (RUSI) on LBP individuals. METHODS AND ANALYSIS: Forty subjects with chronic non-specific LBP (CNLBP), aged from 20 to 50 years, will be randomly allocated into two groups using sealed, consecutively numbered opaque envelopes: (1) study group (SG): CSE monitored by RUSI and (2) control group (CG): identical CSE without monitoring. Interventions will last 30 mins, two times a week for 8 weeks. The primary outcomes include pain intensity, disability and quality of life, and the secondary outcomes will be the postural control static stability, onset timing of trunk muscles activation, ultrasound images of muscle thickness and surface electromyography (sEMG) signal of muscle activities. Outcome measures will be collected at baseline, 4 and 8 weeks during training, and at 6 months follow-up. Data will be collected and analysed by an assessor blinded to group allocation. Effect sizes and mixed-model repeated measures analysis of variance (2 groups×4 time points) will be calculated. ETHICS AND DISSEMINATION: This protocol and informed consent has been approved by the Institutional Research Ethics Committee of the First Affiliated Hospital, Sun Yat-sen University (Approval number: [2020] 254-1). The findings of this study will be disseminated to participants through social networks and will be submitted to peer-reviewed journals and scientific conferences. TRIAL REGISTRATION NUMBER: Chinese Clinical Trial Registry (ChiCTR2000034498).