A randomized trial of behavioral physical therapy interventions for acute and sub-acute low back pain (NCT00373867).

Psychological factors consistent with fear-avoidance models are associated with the development of chronic low back pain (LBP). As a result, graded activity (GA) and graded exposure (GX) have been suggested as behavioral treatment options. This clinical trial compared the effectiveness of treatment-based classification (TBC) physical therapy alone to TBC augmented with GA or GX for patients with acute and sub-acute LBP. Our primary hypothesis was that GX would be most effective for those with elevated pain-related fear. In total, 108 patients enrolled in this clinical trial and were randomly assigned to receive TBC, GA, or GX. Outcomes were assessed by a blinded evaluator at 4 weeks and by mail at 6 months. The primary outcomes for this trial were disability and pain intensity, and the secondary outcomes were fear-avoidance beliefs, pain catastrophizing, and physical impairment. There were no differences in 4-week and 6-month outcomes for reduction of disability, pain intensity, pain catastrophizing, and physical impairment. GX and TBC were associated with larger reductions in fear-avoidance beliefs at 6 months only. Six-month reduction in disability was associated with reduction in pain intensity, while 6-month reduction in pain intensity was associated with reductions in fear-avoidance beliefs and pain catastrophizing. This trial suggests that supplementing TBC with GA or GX was not effective for improving important outcomes related to the development of chronic LBP.