The purpose of this study is to explore the changes in objective walking parameters induced by medullary stimulation in patients with Fail Back Surgery Syndrome, after chronic stimulation, in comparison with preoperative condition.
Age > 18 year old and < or = 70 year old
Patients with chronic neuropathic lumbo-sciatalgia (DN4 score > or = 4/10) as part of a moderate to severe spinal surgery failure syndrome (EVA >50/100), in who a collegial and multidisciplinary indication of medullary stimulation treatment was chosen.
Patients awith Social Security
Vulnerable persons
Patients who are invalid and unable to perform a quantified walk analysis
Contraindication to surgery or anesthesia
Patient not able to complete questionnaires