Spinal cord stimulation combined with exercise in patients diagnosed with persistent spinal pain syndrome. Study protocol for a randomized control trial

A double-blind randomized clinical trial (RCT) has been designed. All participants will be randomized from a pre-set sequence. The intervention design has been elaborated from the CONSORT guidelines. This study has been registered at Clinicaltrial.gov (NCT06272539). Sample size was calculated using G Power® Sample size software (University of Düsseldorf). The calculation was based on a moderate effect size of 0.7 (partial η2 = 0.70, α = .05, power = 0.95), resulting in a total of 40 patients. Assuming a 30% dropout rate, 52 participants will be recruited in total. Two sessions per week will be scheduled for 8 weeks with a total of 16 sessions. Each work session will have a duration of 60 minutes. The exercise will be adapted according to the phases based on the results already published, limiting in each phase the degrees of flexion and extension of the spine to avoid the risk of electrode migration. Primary outcomes will be functionality, satisfaction, strength, psychosocial variables, quality of life and pain perception.