Study sample estimate: by taking the incidence of the Trephined Syndrome in the craniectomized population between 7% - 26%, it takes 100 patients with craniectomy to hope to have data comprising at least 15-20 patients with the studied syndrome. There are about 30 patients craniectomized per year at our institution, but not all of them are transferred to our neuro-rehabilitation unit and hence the duration of the study expected over 5 years.