A population-based, prospective cohort study.
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.
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.
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.
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).
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.
This population-based, prospective cohort study of Washington State workers' compensation claimants with acute low back pain evaluates the effect of early magnetic resonance imaging on health, function, and disability outcomes 1 year following injury. Analyses stratify by injury category (mild/major sprain or radiculopathy) and adjust for demographic, job-related, psychosocial, and injury characteristics.
*Harborview Injury Prevention and Research Center, Department of Pediatrics, School of Medicine, University of Washington, Seattle, WA
†Department of Environmental & Occupational Health Sciences, School of Public Health, University of Washington, Seattle, WA
‡Departments of Radiology and Neurological Surgery, Comparative Effectiveness, Cost & Outcomes Research Center, School of Medicine; Department of Health Services, School of Public Health, University of Washington, Seattle, WA
§Departments of Environmental & Occupational Health Sciences and Health Services, School of Public Health, University of Washington, Seattle, WA; Washington State Department of Labor & Industries, Tumwater, WA
Address correspondence and reprint requests to Janessa M. Graves, MPH, PhD, Harborview Injury Prevention and Research Center, Department of Pediatrics, School of Medicine, University of Washington, Box 359960, 325 Ninth Ave., Seattle, WA 98104; E-mail: email@example.com
Acknowledgment date: October 26, 2011. First revision date: January 26, 2012. Acceptance date: February 20, 2012.
The manuscript submitted does not contain information about medical device(s)/drug(s).
Centers for Disease Control and Prevention (CDC), National Institute for Occupational Safety and Health (NIOSH), and Agency for Healthcare Research and Quality funds were received to support this work.
One or more of the author(s) has/have received or will receive benefits for personal or professional use from a commercial party related directly or indirectly to the subject of this manuscript: e.g., honoraria, gifts, consultancies, royalties, stocks, stock options, decision-making position.