title: Reherniation and failure after lumbar discectomy: a comparison of fragment excision alone versus subtotal discectomy.
abstract: METHODS
  Retrospective review of 259 lumbar discectomies.
  
  
  OBJECTIVE
  To compare rates of reoperation after subtotal discectomy versus established rates after fragment excision.
  
  
  BACKGROUND
  Herniated nucleus pulposes (HNP) and annular morphology influence rates of reherniation after discectomy. Certain patterns are linked to reherniation rates exceeding 20%.
  
  
  METHODS
  We retrospectively reviewed 259 single-level lumbar discectomies performed between 1980 and 2005. Mean follow-up was 60.9 months. In each case, annulotomy and subtotal discectomy was performed in addition to excision of disc fragments. HNP morphology was classified according to the 4-part system of Carragee (type 1: fragment/fissure; type 2: fragment/defect; type 3: fragment/contained; type 4: no fragment/contained). Fisher exact test was used to compare our proportion of patients with reherniation and/or reoperation to Caragee's series in which only fragment excision was performed.
  
  
  RESULTS
  Of 259 cases, 12 (4.5%) reoperations were performed. A significant difference in failure/reoperation rate was noted in type 2 herniations. There was a significantly lower rate of failure and reoperation for type 2 HNP after subtotal discectomy (3.4%) when compared with fragment excision alone (21.2%), P<0.003.
  
  
  CONCLUSIONS
  Subtotal discectomy is an acceptable technique that decreases reherniation after lumbar discectomy.
authors.affiliation: Department of Orthopaedic Surgery, Case Western Reserve University, Cleveland, OH 44106, USA. gwera@yahoo.com
authors.forename: Glenn D
authors.initials: GD
authors.lastname: Wera
authors.forename: Clayton L
authors.initials: CL
authors.lastname: Dean
authors.forename: Uri M
authors.initials: UM
authors.lastname: Ahn
authors.forename: Randall E
authors.initials: RE
authors.lastname: Marcus
authors.forename: Ezequiel H
authors.initials: EH
authors.lastname: Cassinelli
authors.forename: Henry H
authors.initials: HH
authors.lastname: Bohlman
authors.forename: Nicholas U
authors.initials: NU
authors.lastname: Ahn
mesh_terms: D015984:Causality; D017586:Diskectomy / Q000009:adverse effects* / Q000379:methods*; D006801:Humans; D007403:Intervertebral Disc / Q000033:anatomy & histology / Q000473:pathology / Q000601:surgery*; D007405:Intervertebral Disc Displacement / Q000145:classification / Q000473:pathology / Q000601:surgery*; D008159:Lumbar Vertebrae / Q000473:pathology / Q000601:surgery*; D011183:Postoperative Complications / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology; D012008:Recurrence; D012086:Reoperation; D012189:Retrospective Studies; D013525:Surgical Instruments / Q000009:adverse effects / Q000592:standards; D017211:Treatment Failure