Low back pain affects 1 in 4 Australians and is a leading cause for opioid analgesic prescriptions globally. The COMFORT trial aims to support general practitioners to provide opioid stewardship for patients with low back pain. The trial will compare two ways of prescribing an opioid analgesic. The first is the traditional way GPs carefully prescribe the medicine in usual care. The second offers patients other pain relief options in addition to the opioid analgesic. We are not sure which way works best. If successful, the COMFORT trial has the potential to transform care for people with low back pain globally. Musculoskeletal conditions, including low back pain, are among the top 10 reasons for presentation to Australian emergency departments (EDs). Current evidence have shown that timely access to physiotherapy in EDs reduces wait-time, and overall ED length of stay. Primary-contact physiotherapists have been present in some Australian EDs for approximately 20 years, however the level of service provision varies across sites and access is inequitable. This may be because strong evidence of effectiveness is lacking, i.e. predominately observational studies or trials of low quality. The RESHAP-ED trial is a pragmatic, multicentre, two-arm, parallel randomised controlled trial. The trial will determine the effectiveness, cost-effectiveness, and scalability of a primary-contact physiotherapy pathway when compared to usual care (doctors and nurses service) pathway in managing musculoskeletal conditions in the ED. The study hypothesis is that a primary-contact physiotherapy pathway in the emergency department, to help manage patients who present with musculoskeletal conditions, will reduce time spent in emergency departments.