title: Transpedicular Lumbar Endoscopic Surgery for Highly Migrated Disk Extrusions: Preliminary Series and Surgical Technique.
abstract: OBJECTIVE
  Endoscopic surgery for highly migrated lumbar disk extrusions is a challenge even for spine surgeons who are familiar with using endoscopic techniques. Because of the anatomic constraints involved in transforaminal access in endoscopic surgery, an incomplete removal of a highly migrated disk extrusion can result in some cases. Here the authors describe a new technique for accessing extruded lumbar disks that have migrated into the canal directly through a transpedicular approach.
  
  
  METHODS
  A technique for the endoscopic treatment of highly migrated lumbar disk extrusions is presented. Retrospectively, we reviewed a series of 21 consecutive patients operated on with lumbar 3-4, lumbar 4-5, and lumbar 5-sacral 1 highly migrated disk extrusions: preoperative and postoperative clinical data with 1-year follow-up.
  
  
  RESULTS
  A preliminary series of 11 male and 10 female patients with an average age of 56.9 years (from 33-78 years old) who underwent transpedicular endoscopic retrieval of an extruded lumbar disk between 2012 and 2015 is presented. Two patients required revision to transforaminal access, 1 at the same sitting and the other 4 weeks later. The mean visual analog scale score for radicular pain improved from an average pain score before surgery of 8.1-1.7 one year after surgery. No pedicle fractures were encountered.
  
  
  CONCLUSIONS
  Transpedicular endoscopic access to highly migrated lumbar herniated disk extrusions is presented as a unique minimally invasive approach to extruded lumbar herniated disks, especially at L3-4, L4-5, and L5-S1.
authors.affiliation: SRH Hospital Waltershausen- Friedrichroda, Germany.
authors.forename: Guntram
authors.initials: G
authors.lastname: Krzok
authors.affiliation: Department of Neurosurgery, Rhode Island Hospital, The Warren Alpert Medical School of Brown University, Providence, Rhode Island, USA. Electronic address: atelfeian@lifespan.org.
authors.forename: Albert Edward
authors.initials: AE
authors.lastname: Telfeian
authors.affiliation: Ligamenta Spine Centre, Frankfurt am Main, Germany.
authors.forename: Ralf
authors.initials: R
authors.lastname: Wagner
authors.affiliation: Spine Clinic Iprenburg, Veenhuizen, Netherlands.
authors.forename: Menno
authors.initials: M
authors.lastname: Iprenburg
mesh_terms: D000328:Adult; D000368:Aged; D017587:Diskectomy, Percutaneous / Q000379:methods*; D004724:Endoscopy / Q000379:methods*; D005260:Female; D006801:Humans; D007405:Intervertebral Disc Displacement / Q000000981:diagnostic imaging* / Q000601:surgery*; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging* / Q000601:surgery*; D008297:Male; D008875:Middle Aged
keywords: Endoscopic spine surgery; Lumbar disk extrusion; Minimally invasive; Radiculopathy; Transpedicular