Restorative neurostimulation outcomes for mechanical chronic low back pain: delayed-start crossover from optimal medical management and 2-year treatment longitudinal analyses from the RESTORE randomized controlled trial.

In 30 seconds

This postmarket, multicentre, open-label randomised controlled trial extension evaluated restorative neurostimulation for mechanical chronic low back pain associated with lumbar multifidus dysfunction. Of 203 participants initially randomised to neurostimulation or optimal medical management, 80/96 eligible control participants crossed over to active treatment. Improvements in the original treatment group were sustained through 24 months; after one year of active therapy, crossover participants had mean changes from baseline of -21.1±14.8 in ODI, -3.8±2.2 in NRS, and +0.191±0.144 in EQ-5D-5L (all p<.001), comparable in magnitude to the original treatment group at the equivalent treatment timepoint.

Key findings

• At 24 months, the original treatment group’s mean changes from baseline were -24.6±17.1 in ODI, -4.2±2.4 in NRS, and +0.189±0.163 in EQ-5D-5L (all p<.001).
• After one year of active therapy, crossover participants had mean changes of -21.1±14.8 in ODI, -3.8±2.2 in NRS, and +0.191±0.144 in EQ-5D-5L (all p<.001).
• At 12 months, original treatment-group responder rates were 70% for ODI ≥15 point improvement and 53% for ≥50% NRS reduction, versus 17% and 6% in controls.
• Numbers needed to treat ranged from 1.7 to 2.2 and remained similarly low in comparisons involving crossover outcomes and controls.

Why it matters

The findings suggest that improvements in disability, pain, and health-related quality of life can persist for two years in treated participants, and that delayed-start participants may achieve similar improvements after a year of therapy. This is relevant when considering options for mechanical chronic low back pain associated with multifidus dysfunction after conservative care has been exhausted, while recognising that the crossover comparison was not randomised.

What to keep in mind

The delayed-start comparison was nonrandomized, and crossover outcomes used completer analyses; these features limit causal comparisons between early and delayed treatment.