Repetitive Transcranial Magnetic Stimulation Combined with Steroid Joint Injection for the Treatment of Chronic Spinal Pain: Protocol for a Pilot Randomized Controlled Trial

Background:

Chronic spinal pain (CSP) is one of the most common health conditions globally. The pathophysiology of CSP is complex, and it is thought that a spectrum of peripheral and central mechanisms may be involved. (Baron et al., 2016) Steroid joint injections (SJI) are a routine therapeutic intervention for patients with CSP that is recalcitrant to other types of treatment. However, SJI has been shown to have limited long-term efficacy with patients requiring another injection within months to adequately control pain (Won et al., 2020). One option to prolong the analgesic effects of SJI may be to incorporate repetitive transcranial magnetic stimulation (rTMS) as an adjunct therapy. Studies have shown rTMS may be capable of providing long-term pain relief in patients with CSP (Ambriz-Tututi et al., 2016). However, the literature on rTMS in patients with CSP is limited and no study has explored rTMS in patients receiving concurrent SJI for pain control.

Thus, the aims of this study are to determine: (1) the feasibility, tolerability, safety, and perceived patient response to a combined rTMS and SJI intervention, and (2) whether rTMS combined with SJIs (active rTMS group) display trends towards greater benefits for pain and function than SJIs alone (sham rTMS group). We hypothesize that a combined rTMS and SJI intervention be feasible, tolerable, and safe and will show trends towards larger and longer-lasting effects on chronic spinal pain than a sham rTMS and SJI intervention.

Study Design:

This pilot study is a randomized, participant- and assessor-blind controlled trial of active and sham repetitive transcranial magnetic stimulations (rTMS) in a population of individuals with CSP, who are receiving recurrent SJIs at three- to six-month intervals through the St Joseph's Pain Clinic. The rTMS intervention will begin 1-4 weeks after SJI and include a 2-week induction phase with active or sham rTMS delivered 3 times each week. The purpose of the induction phase is to strengthen the effects of rTMS at the start of the treatment through multiple sessions in a relatively short period of time. A maintenance phase will follow and in weeks 3, 4, 6, 8, and 12 participants will receive a single active or sham rTMS session. Pain severity will be assessed weekly using an electronic diary from baseline (the week of SJI until week 24). Disability and quality of life will be assessed at baseline, 4, 8, 12, 18 and 24 weeks.