Screening visit (D-3)
D-3-D0, NRS, pain
Verification of inclusion and exclusion criteria. Patients will be provided with the information sheet and will be asked to sign the informed consent form. The patient will be provided with NRS forms (3 assessments per day for 48 hours). For organizational reasons, this screening visit will be held on a Friday. NRS scores will be recorded on Saturday and Sunday so that inclusion or exclusion of the patient can be decided on Monday.Study plan: the study will last 24 days (D-3 to D21) including a 3-day inclusion period (D-3-D0), a 5-day treatment period (D0-D4) and a 16-day follow-up period after stopping treatment (D8, D14, D21). Treatment consists of a daily tDCS session on 5 consecutive days. Patients will be randomized to 2 arms (1:1 ratio): active tDCS and sham tDCS. Patients and investigators will be blinded to the results of randomization (double-blind). The primary objective will be a significant reduction of pain evaluated by a numerical rating scale (NRS) from 0 to 10 between the baseline score recorded between D-3 and D0 and the score recorded 4 days after stopping treatment (D8)