Spinal Cord Stimulation for Refractory Pain Randomized Controlled Trial: the PAcStim RCT

Neuropathic pain affects 6-10% of the global population and is poorly managed - current drug treatments succeed in only \~25% of patients. Spinal cord stimulation (SCS) modulates pain by electrically stimulating spinal dorsal column fibres. The newer paresthesia-free mode (PF-SCS, 500-10,000 Hz) appears more effective and tolerable than traditional paresthesia-based SCS, with superior outcomes shown in the SENZA-RCT. All promising PF-SCS studies have been unblinded, making them susceptible to placebo effects. The one blinded RCT that exists had significant methodological flaws (no washout period, single baseline measurement) that biased results toward the null. A blinded, multi-centre, crossover RCT in 90 patients comparing 6 weeks of active PF-SCS vs. 6 weeks of placebo stimulation, with a 2-week washout in between - designed to correct the flaws of the prior trial and definitively establish whether PF-SCS works beyond placebo.

Inclusion criteria * Age 18 years or older * Severe NP in the axial locations (neck and back) and/ or the limbs * Undergoing an SCS implantation with a PF device Exclusion criteria * Previously implanted with an SCS device * Not fluent in English * Unable to provide written informed consent