title: Percutaneous endoscopic discectomy for extraforaminal lumbar disc herniations: extraforaminal targeted fragmentectomy technique using working channel endoscope.
abstract: METHODS
  A retrospective analysis of 41 patients operated for excision of soft lumbar extraforaminal disc herniation (EFDH) by percutaneous endoscopic extraforaminal approach under local anesthesia by a new technique.
  
  
  OBJECTIVE
  To describe a new and safer percutaneous endoscopic technique for the removal of soft EFDH and report the results on the basis of a new objective criterion modified from Oswestry Disability Index (ODI).
  
  
  BACKGROUND
  EFDHs usually occur in older patients and present with atypical symptoms. Their diagnosis and treatment are still controversial, with various authors describing open midline or paraspinal approaches using the microscope with varying amounts of success. Percutaneous endoscopic techniques have traditionally been considered unsuitable for these herniations.
  
  
  METHODS
  Forty-one patients with a soft EFDH were subjected to percutaneous endoscopic discectomy with the new technique. In our technique, the skin entry point is medial and the angle of approach steeper as compared with the earlier described endoscopic techniques. This might help in avoiding exiting root injury and increasing the efficacy of the procedure. The results were analyzed on the basis of percentage change in ODI as compared with preoperative values.
  
  
  RESULTS
  Mean follow-up was 34.1 month. Mean VAS score for radicular pain improved from 8.6 to 1.9, and mean ODI improved from 66.3 to 11.5. Overall, 92% of patients experienced satisfactory outcome. Two patients had poor outcome due to the need for subsequent open surgery.
  
  
  CONCLUSIONS
  Percutaneous endoscopic discectomy using the "extraforaminal targeted fragmentectomy" technique is an effective and safe procedure for the select group of patients with a soft EFDH.
authors.affiliation: Department of Neurosurgery, Wooridul Spine Hospital, Seoul, Korea.
authors.forename: Gun
authors.initials: G
authors.lastname: Choi
authors.forename: Sang-Ho
authors.initials: SH
authors.lastname: Lee
authors.forename: Arun
authors.initials: A
authors.lastname: Bhanot
authors.forename: Pradyumna Pai
authors.initials: PP
authors.lastname: Raiturker
authors.forename: Yu Sik
authors.initials: YS
authors.lastname: Chae
mesh_terms: D000328:Adult; D000368:Aged; D004185:Disability Evaluation; D017587:Diskectomy, Percutaneous / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods*; D019723:Endoscopes; D004724:Endoscopy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007405:Intervertebral Disc Displacement / Q000150:complications / Q000503:physiopathology / Q000601:surgery*; D007866:Leg; D008159:Lumbar Vertebrae; D008297:Male; D008866:Microsurgery; D008875:Middle Aged; D010146:Pain / Q000209:etiology / Q000503:physiopathology / Q000601:surgery; D010147:Pain Measurement; D010292:Paresthesia / Q000188:drug therapy / Q000209:etiology; D017060:Patient Satisfaction; D012008:Recurrence; D012086:Reoperation; D012189:Retrospective Studies; D013126:Spinal Nerve Roots / Q000503:physiopathology; D016896:Treatment Outcome