title: Early imaging for acute low back pain: one-year health and disability outcomes among Washington State workers.
abstract: METHODS
  A population-based, prospective cohort study.
  
  
  OBJECTIVE
  To evaluate the association of early imaging and health and disability status 1 year following acute low back injury, among a population-based sample of Washington State workers' compensation claimants.
  
  
  BACKGROUND
  Use of early diagnostic magnetic resonance imaging (MRI) for low back pain (LBP) contributes to increasing health care costs but may not lead to better outcomes than delayed imaging. In the worker's compensation system, LBP is common and costly. This research examines the association between early MRI among workers with LBP and health outcomes (pain intensity, Roland disability score, and 36-Item Short Form Health Survey scores) and disability status 1 year after injury.
  
  
  METHODS
  This nonrandomized prospective cohort study of Washington State workers' compensation claimants with nonspecific LBP used administrative claims and interview data. Multivariable regression methods were used to estimate change in health outcome scores, the relative risk of disability at 1 year, and the rate of recovery 1 year after injury.
  
  
  RESULTS
  Of 1226 participants, 18.6% received early MRI. Most (77.9%) had mild/major sprains and 22.1% had radiculopathy. Participants with early MRI differed significantly at baseline in pain, function, and psychosocial variables. After adjusting for covariates, early imaging was not associated with substantial differences in 1-year health outcomes for sprains or radiculopathy. For workers with mild/major sprain, early imaging was associated with a 2-fold increase in the likelihood of work disability benefits at 1 year (adjusted relative risk: 2.03, 95% confidence interval: 1.33-3.11). Early imaging was not associated with an increased risk of long-term disability for workers with radiculopathy (adjusted relative risk: 1.31, 95% confidence interval: 0.84-2.05). For both groups, early MRI was associated with longer disability duration (P < 0.001).
  
  
  CONCLUSIONS
  Among workers with LBP, early MRI is not associated with better health outcomes and is associated with increased likelihood of disability and its duration. These associations warrant further testing in a randomized controlled trial. Our findings suggest that adherence to evidence-based guidelines is an important factor in ensuring that workers receive the highest quality care for occupational injuries.
authors.affiliation: Harborview Injury Prevention and Research Center, Department of Pediatrics, School of Medicine, University of Washington, Seattle, WA, USA.
authors.forename: Janessa M
authors.initials: JM
authors.lastname: Graves
authors.forename: Deborah
authors.initials: D
authors.lastname: Fulton-Kehoe
authors.forename: Jeffrey G
authors.initials: JG
authors.lastname: Jarvik
authors.forename: Gary M
authors.initials: GM
authors.lastname: Franklin
mesh_terms: D000328:Adult; D019567:Back Injuries / Q000150:complications; D004185:Disability Evaluation; D042241:Early Diagnosis; D005260:Female; D006304:Health Status; D006801:Humans; D017116:Low Back Pain / Q000175:diagnosis* / Q000209:etiology; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016272:Occupational Health / Q000706:statistics & numerical data; D010147:Pain Measurement / Q000379:methods; D011446:Prospective Studies; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D011795:Surveys and Questionnaires; D013997:Time Factors; D014861:Washington; D014942:Workers' Compensation / Q000706:statistics & numerical data*; D055815:Young Adult