ABSTRACT Objective: Identify whether people with people with acute low back pain (LBP) display spinal movement impairments during clinical tests. Compare the prevalence of impairments in people with acute LBP to that of people with chronic LBP. Examine the effect on symptoms of systematically modifying impairments. Design: Secondary analysis of data from a cross-sectional study on LBP. Methods: 183 people with LBP were examined by a physical therapist using a standardized examination. Participants performed 9 primary tests using their preferred strategy. The clinician determined whether an impairment was present or absent. Participants reported the effect of the primary test on symptoms. If an impairment was present, it was modified during a secondary test. Participants reported the effect of the secondary test on symptoms relative to symptoms with the primary test. Chi-square tests of independence were used to test for differences in the proportion of impairments between people with acute LBP and people with chronic LBP. A McNemar-Bowker test was used to test whether there was a change in symptoms from the primary test to the secondary test. Results: People with acute LBP displayed spinal movement impairments and the prevalence was similar to that of people with chronic LBP for 7 of the 9 primary tests. Most participants with symptomatic impairments reported their symptoms improved when the impairment was modified. Conclusion: Spinal movement impairments are prevalent in people with acute LBP and may be modified during clinical tests to improve LBP symptoms. Keywords: low back pain, acute, impairment, movement, clinical, treatment

The authors have declared no competing interest.

This research received funding from the Foundation for Physical Therapy (Grant No. 94R-03-N0R-02), KK is supported by a training grant from National Institutes of Health (Grant No. T32DH007434). The funders of the study had no other role in the study design, data collection, data analysis, data interpretation, or writing of the current research. KK reports grant funding from the NIH during conduct of the study. RD reports grant funding from the NIH during conduct of the study. LVD reports grant funding from the NIH and from the Academy of Orthopaedic Physical Therapy during conduct of the study. No other disclosures were reported.

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