title: The influence of adjacent level disc disease on discectomy outcomes.
abstract: OBJECTIVE
  The state of adjacent level discs and its impact on surgical outcomes following single-level lumbar discectomy have not been previously investigated. The purpose of the present study was to determine if a significant relationship exists between the degree of preoperative adjacent level disc degeneration and post-operative clinical outcomes following lumbar discectomy.
  
  
  METHODS
  This study retrospectively used preoperative magnetic resonance imaging (MRI) and prospectively collected data from a randomized clinical trial at two tertiary-care academic hospitals. Patients who underwent a primary, single-level lumbar discectomy were included. Exclusion criteria included prior lumbar surgery. Outcome measures were the Modified Oswestry Disability Index (ODI) score and Visual Analog Scale (VAS) scores for back and leg pain. These were recorded at baseline and at 3 months, 1, and 2 years postoperatively. An independent reviewer graded adjacent level disc degeneration on all preoperative MRIs using the Pfirrmann grading scale. These data were then analyzed for correlation with each outcome measure.
  
  
  RESULTS
  Forty-seven patients were included in the study. No statistically significant correlations were found when comparing preoperative 3-month or 1-year postoperative scores or change from baseline of any outcome measure between Pfirrmann grades. Only about half the patients had 2-year follow-up, but at that time point a statistically significant difference in back VAS scores was observed between Pfirrmann groups. No other significant differences were observed at that point.
  
  
  CONCLUSIONS
  The degree of preoperative adjacent level degeneration does not significantly affect functional or pain relief outcomes following lumbar discectomy up to 1 year after surgery.
authors.affiliation: Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.|Department of Orthopedic Spine Surgery, Harvard Medical School, Brigham and Women's Hospital, 75 Francis St., Boston, MA, 02115, USA.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Briseño
authors.affiliation: Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Rishabh D
authors.initials: RD
authors.lastname: Phukan
authors.affiliation: Department of Orthopedic Spine Surgery, Harvard Medical School, Brigham and Women's Hospital, 75 Francis St., Boston, MA, 02115, USA. dleonard7@partners.org.
authors.forename: Dana A
authors.initials: DA
authors.lastname: Leonard
authors.affiliation: Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Tyler L
authors.initials: TL
authors.lastname: Herzog
authors.affiliation: Department of Orthopedic Spine Surgery, Harvard Medical School, Brigham and Women's Hospital, 75 Francis St., Boston, MA, 02115, USA.
authors.forename: Charles H
authors.initials: CH
authors.lastname: Cho
authors.affiliation: Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Joseph H
authors.initials: JH
authors.lastname: Schwab
authors.affiliation: Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Kirkham B
authors.initials: KB
authors.lastname: Wood
authors.affiliation: Department of Orthopedic Spine Surgery, Harvard Medical School, Brigham and Women's Hospital, 75 Francis St., Boston, MA, 02115, USA.
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Bono
authors.affiliation: Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Thomas D
authors.initials: TD
authors.lastname: Cha
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017586:Diskectomy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D055959:Intervertebral Disc Degeneration / Q000175:diagnosis* / Q000601:surgery; D008159:Lumbar Vertebrae / Q000601:surgery*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D016896:Treatment Outcome; D055815:Young Adult
keywords: Adjacent level disease; Discectomy; Lumbar spine; Outcomes; Quality of life