title: Magnetic resonance imaging predictors of surgical outcome in patients with lumbar intervertebral disc herniation.
abstract: METHODS
  A retrospective cohort design.
  
  
  OBJECTIVE
  To determine whether baseline magnetic resonance imaging findings, including central/foraminal stenosis, Modic change, disc morphology, facet arthropathy, disc degeneration, nerve root impingement, and thecal sac compression, are associated with differential surgical treatment effect.
  
  
  BACKGROUND
  Intervertebral disc herniation remains the most common source of lumbar radiculopathy treated either with discectomy or nonoperative intervention. Although magnetic resonance imaging remains the reliable "gold standard" for diagnosis, uncertainty surrounds the relationship between magnetic resonance imaging findings and treatment outcomes.
  
  
  METHODS
  Three hundred seven "complete" images from patients enrolled in a previous trial were de-identified and evaluated by 1 of 4 independent readers. Findings were compared with outcome measures including the Oswestry Disability Index. Differences in surgery and nonoperative treatment outcomes were evaluated between image characteristic subgroups and TE determined by the difference in Oswestry Disability Index scores.
  
  
  RESULTS
  The cohort comprised 40% females with an average age of 41.5 (±11.6) years, 61% of whom underwent discectomy for intervertebral disc herniation. Patients undergoing surgery with Modic type I endplate changes had worse outcomes (-26.4 vs. -39.7 for none and -39.2 for type 2, P = 0.002) and smaller treatment effect (-3.5 vs. -19.3 for none and -15.7 for type 2, P = 0.003). Those with compression of ≥1/3 showed the greatest improvement within the surgical group (-41.9 for ≥1/3 vs. -31.6 for none and -38.1 for <1/3, P = 0.007) and the highest TE (-23 compared with -11.7 for none and -15.2 for <1/3, P = 0.015). Furthermore, patients with minimal nerve root impingement demonstrated worse surgical outcomes (-26.5 vs. -41.1 for "displaced" and -38.9 for "compressed," P = 0.016).
  
  
  CONCLUSIONS
  Among patients with intervertebral disc herniation, those with thecal sac compression of 1/3 or more had greater surgical treatment effect than those with small disc herniations and Modic type I changes. In addition, patients with nerve root "compression" and "displacement" benefit more from surgery than those with minimal nerve root impingement.
  
  
  METHODS
  2.
authors: Department of Medicine, Dartmouth Medical School, Lebanon, NH 03756, USA.
authors: Jon D
authors: JD
authors: Lurie
authors: Rachel A
authors: RA
authors: Moses
authors: Anna N A
authors: AN
authors: Tosteson
authors: Tor D
authors: TD
authors: Tosteson
authors: Eugene J
authors: EJ
authors: Carragee
authors: John A
authors: JA
authors: Carrino
authors: Jay A
authors: JA
authors: Kaiser
authors: Richard J
authors: RJ
authors: Herzog
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D004185:Disability Evaluation; D017586:Diskectomy / Q000379:methods*; D005260:Female; D006801:Humans; D007405:Intervertebral Disc Displacement / Q000000981:diagnostic imaging / Q000601:surgery* / Q000628:therapy; D016014:Linear Models; D008159:Lumbar Vertebrae / Q000473:pathology / Q000601:surgery*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011843:Radiculopathy / Q000000981:diagnostic imaging / Q000601:surgery; D011859:Radiography; D012189:Retrospective Studies; D011795:Surveys and Questionnaires; D016896:Treatment Outcome