PROJECT SUMMARY Low back pain affects nearly half of all Americans per year and accounts for nearly three million annual emergency department (ED) visits. In nearly two thirds of these visits, an opioid medication is administered or prescribed, making low back pain the most common reason for opioid prescribing in the emergency care setting and in the general population. Despite this medication-based treatment strategy, many patients with low back pain continue to do poorly after an ED visit: nearly half of all patients report persistent functional impairment at three months, and one in five patients report continued opioid use. Clearly there is a need for an alternative treatment approach that improves low back pain symptoms and reduces the need to use opioid medications. Multiple randomized trials have demonstrated that early referral to physical therapy in the outpatient setting is efficacious for low back pain, but it is unknown whether these same benefits can be extended to patients evaluated by physical therapists in ED settings – which differ from clinic-based settings due to the acuity/severity of pain necessitating an emergency visit and accompanying psychosocial stressors. We previously developed, pilot-tested, and refined an “embedded” ED physical therapy intervention protocol for low back pain, in which a dedicated physical therapist is placed on the primary ED treatment team to evaluate and treat patients with low back pain early in their overall treatment course. The ED physical therapist uses a diagnosis-driven treatment protocol to deliver an integrated mind and body intervention grounded in a biopsychosocial model of pain. In our preliminary work at a single site, ED patients that received ED physical therapy, as compared to usual care, reported greater improvements in pain-related functioning and less use of opioid medications over three months of follow-up. We now seek to evaluate whether this embedded ED physical therapy intervention can be feasibly delivered with high fidelity at multiple other sites and demonstrate that we can consistently collect electronic health record and patient-reported outcomes of interest. We will then use the findings from this multi-site feasibility trial to justify and inform a full-scale multi-site cluster-randomized clinical trial of an embedded ED physical therapy care model for low back pain.