Effectiveness of lumbar stabilization exercise with real-time ultrasound imaging biofeedback on lumbar multifidus muscle cross-sectional area in individuals with non-specific chronic low back pain: a study protocol for a randomized controlled trial

Background: Structural impairment of the lumbar multifidus muscle, such as reduced cross-sectional area, is evident among individuals with chronic low back pain. Real-time ultrasound imaging (RUSI) biofeedback has been reported to improve preferential activation of as well as retention in the ability to activate the lumbar multifidus muscle during lumbar stabilization exercises (LSE). However, evidence of the effectiveness of this treatment approach in individuals with non-specific chronic low back pain (NCLBP) is still limited. The purpose of this study is, therefore, to determine the effectiveness of LSE with RUSI biofeedback on lumbar multifidus muscle cross-sectional area in individuals with NCLBP. Methods/Design: This study is a prospective, single-center, assessor-blind, three-arm, parallel randomized controlled trial to be conducted at National Orthopedic Hospital, Kano State, Nigeria. Ninety individuals with NCLBP will be randomized in a 1:1:1: ratio to receive LSE, LSE with RUSI biofeedback, or minimal intervention. All participants will receive treatment twice weekly for 8 weeks. The primary outcome will be the lumbar multifidus muscle cross-sectional area. The secondary outcomes will include pain (Numerical Pain Rating Scale), functional disability (Roland-Morris Disability Questionnaire), and quality of life (12-Item Short-Form Health Survey). All outcomes will be assessed at baseline, 8 weeks post-intervention, and 3 months follow-up. Discussion: To our knowledge, this study will be the first powered randomized controlled trial to compare the effectiveness of LSE training with and without RUSI biofeedback in individuals with NCLBP. The outcome of the study may provide evidence for the effectiveness of LSE with RUSI biofeedback on enhancing the recovery of the lumbar multifidus muscle in individuals with NCLBP.