Transsacral epiduroscopy demonstrates high responder rate in patients with chronic non-specific (lumbo)sciatica - 12-month results of a single-center observational study - S. Weidert; S. Altmann; E. Suero; C. Neuerburg; W. Böcker; B. Wegener; C. Becker; A. Greiner; R. Ibrahim (Brain and Spine)