Combining Brain Stimulation and Physiotherapy for the Management of Chronic Low Back Pain

A figure-of-8 coil connected to a biphasic Magstim Rapid 2 stimulator (The MagstimCo, Whitland, UK) will be used. Coil orientation and position will be guided throughout the experiment by a neuronavigation system (Brainsight, Rogue research, Montreal, QC, Canada). Stimulation parameters will be obtained by measuring the motor threshold of the first right interosseous muscle, then the rTMS intensity will be set at 110% of this motor threshold. High frequency (HF) rTMS consisting of 60 trains of 5 s at 10 Hz with 15 s intertrain intervals, for a total of 3000 pulses per session, will be used. The coil will be positioned over the left dorsolateral PFC using the BeamF3 methods.

A sham coil will be used (e.g. equipped with a magnetic shield that blocks the magnetic field). The sham stimulation will last the same duration as the active rTMS and will be located over the same area (dorso-lateral prefrontal cortex).

Participants will receive 6 intervention sessions (45 min) over 6 weeks by a physiotherapist. The objective of this intervention is to identify biopsychosocial factors that may impede recovery and to address these factors within the physiotherapist's scope of practice. Physiotherapists will use strategies such as the establishment of common goals and therapeutic alliance, the use of behavior change model, motivational interview, education on pain neurophysiology, gradual exposure to movement and stress management strategies (e.g. breathing techniques). Participants allocated to PiP groups will have access to a website offering support information related to understanding their pain (e.g. pain neuroscience education), myths and false beliefs related to back pain, understanding the impact of psychological factors on their pain, self-management strategies, and healthy lifestyle habits. This site will be freely available to participants during the course of the study.

Participants will receive 6 intervention sessions (45 min) over 8 weeks by a physiotherapist. This is a pragmatic group that aims to represent real-word clinical practice i.e. interventions commonly used in physiotherapy to manage CLBP. All interventions that a physiotherapist can deliver in the province of Quebec will be allowed (e.g. manual therapy, exercises). No training will be provided to better reflect usual clinical practice in physiotherapy.