Clinical practice guidelines recommend a conservative approach to management of acute low back pain (LBP). The present study sought to determine whether health care utilization and the physician's initial management of work-related LBP were associated with disability duration. Clinical management information was obtained for 98 randomly selected, workers' compensation claimants with acute, uncomplicated, disabling work-related LBP. Length of disability was based on indemnity (wage replacement) payments. Disability was significantly associated with increased utilization of specialty referrals (P = 0.013) and provider visits (P < 0.001), use of magnetic resonance imaging (P = 0.003), and use of opioids for more than 7 days (P = 0.013). Effects of early diagnostic imaging (first 30 days of care) on length of disability were observed (P = 0.001). Patients whose treatment course did not involve extended opioid use and early diagnostic testing were 3.78 times more likely (95% confidence interval, 1.6 to 8.9) to have gone off disability status by the end of the study. The nature of the association between these initial clinical management aspects and LBP disability duration merits further exploration.