Restorative Neurostimulation for Chronic Low Back Pain: Real-World Evidence

Restorative neurostimulation was found to be feasible in routine clinical practice and resulted in improvements in pain, disability, and quality of life among patients with chronic mechanical low back pain, according to the results of a study published in World Neurosurgery.

Patients (N=44) with chronic mechanical low back pain with minimal leg involvement were recruited from the Klinikum Itzehoe in Germany between 2018 and 2020 to participate in the study. The patients underwent surgical implantation of a ReActiv8 (Mainstay Medical) system connected to an implanted pulse generator. The devices were programmed 14 days after implantation to deliver smooth multifidus contractions at a frequency of 20 Hz, a width of 214 μs, and an amplitude that was comfortable and pain-free for each patient. Change in low back pain numeric rating scale (NRS), Oswestry Disability Index (ODI), and 5-level EuroQoL 5-Dimension (EQ-5D-5L) scores from baseline were evaluated for 1 year.

The mean age of study participants was 54 (interquartile range [IQR], 11.5) years, 61% were women, mean BMI was 28.2 (IQR, 5.2) kg/m², and the median duration of low back pain was 5.8 (IQR, 8.45) years.

Significant improvements in pain NRS (mean, 7.6 vs 3.9; P <.001), ODI (mean, 43.0 vs 25.9; P <.001), and EQ-5D-5L (mean, 0.504 vs 0.755; P <.001) scores were observed from baseline to month 12, respectively. Similar findings were observed in the last-carried-forward analysis, which included the 2 patients who withdrew from the study and the 2 patients who were lost to follow-up.

At 1 year following implantation, 68% of patients reported a 30% or greater improvement in NRS, 52% reported a 50% or greater improvement in NRS score, 74% reported a 10-point or greater improvement in ODI score, and 55% reported a 20-point or greater improvement in ODI score.

One patient required surgical revision due to lead fracture, and 1 patient required anesthetic injection due to isolated sacroiliac joint pain. The 2 patients who withdrew from the study did so due to lack of efficacy, and the devices were subsequently removed. No serious procedural or device-related events were observed.

Limitations of this study include the small sample size and lack of a comparator cohort.

The results of this study were in line with other published studies, reinforcing that restorative neurostimulation may be a viable and safe intervention for mechanical chronic LBP. The study authors conclude, “The meaningful clinical improvements achieved in pain, disability, and quality of life in our real-world cohort suggest that these published outcomes achieved in the clinical trial setting can also be achieved in routine clinical practice.”

Disclosure: This study was sponsored by Mainstay Medical. Multiple study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.