5-year longitudinal follow-up of patients treated for chronic mechanical low back pain using restorative neurostimulation.

Abstract

Chronic mechanical low back pain (CLBP) often stems from dysfunction of the multifidus muscle, leading to impaired motor control and pain. Restorative neurostimulation has emerged as a novel treatment targeting this dysfunction by delivering electrical stimulation to the medial branches of the L2 dorsal rami to restore multifidus activation. This prospective, open-label, postmarket clinical follow-up study aimed to evaluate 5-year clinical outcomes and device utilization trends in a cohort of 42 patients with CLBP treated across five UK sites with restorative neurostimulation via an implanted ReActiv8 neurostimulation system. Patients were followed for 5 years, with assessments of pain (Numerical Rating Scale (NRS)), disability (Oswestry Disability Index (ODI)), and health-related quality of life (EuroQol-5 Dimension, 5 Level (EQ-5D-5L)) at baseline and regular intervals. Therapy utilization was collected via implantable device logs. At 5 years, 34/42 patients (81%) completed follow-up. Significant and durable improvements were observed in pain (mean NRS reduced from 7.0 to 3.2), disability (mean ODI reduced from 46.6 to 26.1), and quality of life (EQ-5D index increased from 0.426 to 0.703). A total of 82% of patients achieved a minimally clinically important change in either pain or disability, and 62% were pain remitters (NRS ≤3). Device usage averaged 1106 hours over 5 years, with reductions in usage over time. Lower usage was associated with non-response, though causality could not be determined. Restorative neurostimulation provides robust, sustained improvements in pain, function, and quality of life in patients with CLBP associated with multifidus dysfunction. These results support its long-term efficacy and safety in real-world clinical practice. ClinicalTrials.gov Identifier: NCT01985230.