Physical Therapy Informed by Acceptance and Commitment Therapy (PACT) Versus Usual Care Physical Therapy for Adults With Chronic Low Back Pain: A Randomized Controlled Trial

•ACT informed physical therapy (PACT) is acceptable for people with CLBP•PACT participants reported significantly better functioning at 3 months’ follow-up•Improvements compared to standard physical therapy were not maintained at 12 months•PACT can be delivered with high fidelity by trained physical therapists Chronic low back pain (CLBP) is a major cause of global disability and improving management is essential. Acceptance and commitment therapy (ACT) is a promising treatment for chronic pain but has not been modified for physical therapy. This randomized controlled trial (RCT) compared physical therapy informed by ACT (PACT) against standard care physical therapy for patients with CLBP. Patients with CLBP (duration ≥12 weeks, mean 3 years) were recruited from physical therapy clinics in 4 UK public hospitals. The Roland-Morris Disability Questionnaire (RMDQ) at 3 months’ post-randomization was the primary outcome. Two hundred forty-eight participants (59% female, mean age = 48) were recruited and 219 (88.3%) completed measures at 3 and/or 12 months’ follow-up. At 3 months, PACT participants reported better outcomes for disability (RMDQ mean difference = 1.07, p = .037, 95% CI = −2.08 to −.07, d = .2), Patient Specific Functioning (p = .008), SF12 physical health (p = .032), and treatment credibility (p < .001). At 12 months’ follow-up, there were no significant differences between groups. PACT was acceptable to patients and clinicians and feasible to deliver. Physical therapists incorporated psychological principles successfully and treatment was delivered with high (≥80%) fidelity. Our results may inform the management of CLBP, with potential benefits for patients, health care providers, and society. Psychologically informed physical therapy has great potential but there are challenges in implementation. The training and support included in the PACT trial enabled the intervention to be delivered as planned. This successfully reduced disability in the short but not long term. Findings could inform physical therapists’ treatment of CLBP.