Background: Overcrowding in emergency departments (ED) is a major concern and reports show that Canada has among the longest ED wait and length of stay times. Patients suffering from musculoskeletal disorders (MSKD) represent at least 25% of all ED visits and this number is expected to increase with the aging population. Physiotherapists (PT) have been identified as expert clinicians to care for patients with MSKD and new collaborative models of care involving PTs have been emerging in ED. Traditionally, PTs provide care in EDs only after physicians have assessed patients and made a referral for physiotherapy. More autonomous PT involvement in ED models of care allows for efficient collaborative practice with physicians and other professionals and can benefit ED performance, patient outcomes, as well as healthcare resource utilization. These advanced practice physiotherapy (APP) models of care often allow for a more extended scope of practice for PTs in which they have direct access to patients without a physician referral, triage patients and sometimes prescribe medical imaging or medication. ED APP has emerged as a promising new ED model of care, but evidence of the effectiveness of such models is limited. Only a few RCTs have been conducted and no studies have assessed the efficacy or cost-utility of APP models of care in Canadian EDs. Evaluation of the benefits of such models is highly context-dependent and systematic evaluation of these models is warranted to further support implementation in Canada. Objectives: To compare the effectiveness of a direct access APP model of care compared to usual physician ED care for persons presenting to an ED with a MSKD, in terms patient-related outcomes, health care resources utilization and costs.

Methods: This trial is a multicenter stepped-wedge cluster RCT with a cost analysis. Six EDs (clusters) will be randomized to a treatment sequence where patients will either be managed by an ED PT or receive usual ED physician care without the intervention of a PT. Seven hundred and forty four patients with a MSKD will be recruited. Main outcome measures will be the Brief Pain Inventory as well as the EQ-5D-5L for economic outcomes. Secondary measures will include validated self-reported disability questionnaires and other healthcare utilization outcomes such as prescription of imaging tests and medication. Adverse events and re-visits to ED will also be monitored. Outcomes will be collected at inclusion, at ED discharge and at 4, 12 and 26 weeks following the ED visit. Health care costs will be measured from the perspective of the public system using Time-Driven Activity Based Costing. Per-protocol and intention-to-treat analyses will be performed using linear mixed-models with a random effect for cluster and fixed effect for time. The diverse and complementary research team assembled has the required methodological expertise to successfully complete this trial and several knowledge users have been involved which assures the feasibility and maximizes the impacts of this project.

Discussion: MSKD not only represent a significant economic burden in Canada, but also have a significant impact on our health care system and the quality of life of Canadians. By providing an innovative pathway of access to care, APP care could help relieve pressure on Canadian ED and help provide efficient care for Canadians with MSKD.