Mechanisms and Outcome-Prognostication for Paresthesia-based and -Free Spinal Cord Stimulation

What this study is about

Spinal cord stimulation (SCS) relies on stimulation of pain-relieving pathways in the spinal cord to treat chronic neuropathic pain. Traditional paresthesia-based SCS (PB-SCS) relies on providing analgesia through stimulation of spinal cord dorsal columns but it is often associated with attenuation of analgesic benefit and lack of acceptance of paresthesias. Recently introduced three different paresthesia-free (PF-SCS) modes of stimulation aim to overcome limitations of PB-SCS. Several questions regarding PB and PF SCS modes remain unanswered including the mechanisms of therapeutic benefit, criteria for selecting patients likely to benefit, and long-term outcomes. A concerted effort is required to understand and optimize utilization of SCS. This project has the twin goals of using neuroimaging techniques to understand mechanisms that underlies analgesic benefit from PB/PF-SCS modes and to identify criteria for selecting patients based on monitoring of pain and its related domains in patients undergoing SCS trials. Achieving these objectives will increase probability of analgesic benefit while minimizing adverse effects and knowledge gains from this study will be applicable to other therapies for chronic pain conditions.

Who can join (things the study team will check)

✅ You may be able to join if…

• Adults, 18 - 80 years of age, with refractory neuropathic pain (as per clinical features and DN4 score > 3/10) in back and or lower limbs for more than 3 months following lumbar spine surgery
• Severity of pain > 3/10 on NRS and ODI score for disability >40/100; and
• Pain refractory to conventional medical management tried for at least 3 months.

🚫 You may not be able to join if…

• Age < 18 or age ≥ 80 years;
• Previous trial or implantation of SCS system;
• Procedural contraindications to SCS including extensive thoracolumbar spine surgery, moderate-to-severe central canal stenosis, coagulopathy, local or systemic infection;
• Pregnancy;
• Opioid dose > 200 mg OMED;
• Psychiatric or psychological disorder likely to impact perception of pain;
• Inability to comply with the study interventions or evaluate treatment outcomes;
• Mechanical spine instability as per flexion/extension lumbar X-rays;
• Ongoing litigation issues related to the pain; and
• Concomitant peripheral neuropathy or myopathy or central neuropathic pain (e.g. post-stroke pain).

Where this trial is running

• Toronto Western Hospital, Toronto, Ontario, Canada

Who to contact

Anuj Bhatia, MD FRCPC · (416) 603-5800 · anuj.bhatia@uhn.ca

It's completely normal to call and ask questions before deciding anything. Mention the study ID: NCT03852381.