Evaluation of the effects of osteopathic manipulative treatment associated with transcranial direct current stimulation in chronic nonspecific low back pain. A protocol for a randomised controlled trial

Objective This study aimed to investigate the effects of osteopathic manipulative treatment (OMT) combined with transcranial direct current stimulation (tDCS) in individuals with chronic nonspecific low back pain (CNSLBP). Methods This will be a randomized controlled clinical trial of three groups with blinded evaluators and participants. The study will be conducted at the at the Rehabilitation Center of the Irmandade da Santa Casa de Misericórdia de São Paulo, São Paulo, Brazil. Participants 72 participants of both sexes, with CNSLBP. Intervention Participants will be randomly allocated into three groups, with 24 participants per group (Group 1: active tDCS + active OMT; Group 2: placebo tDCS + placebo OMT; Group 3: placebo tDCS + active OMT). Assessments will be conducted before and after the intervention protocol and 1 month after the end of the entire process. For tDCS, 10 sessions of 20 minutes over 2 weeks (5 sessions per week). OMT will be performed by an osteopath, with two consultations, one per week, before the first and sixth sessions of tDCS. Main outcome measures The primary outcome will be the visual analog pain scale, and the Roland Morris disability and EuroQol-5D quality of life questionnaires will be used as secondary. Analysis The statistical analysis will be calculated using linear mixed models and based on intention-to-treat. The level of significance will be set at α = 5%.