The Effect of Exercise on Recent Onset Low Back Pain in the Emergency Department

Low back pain (LBP) is the leading contributor to years lived with disability and an important contributor to healthcare costs and time off work. Exercise is effective for chronic low back pain, but there is a lack of evidence to inform whether exercise in the emergency department is effective for people with acute (<1 week) low back pain.

The objectives of this randomized controlled trial are:

1. To determine the effectiveness of an exercise intervention delivered in the ED in comparison to usual ED care on pain, function, global rating of change, patient satisfaction, and adverse effects in adults with recent onset LBP (< 1 week).
2. To determine the feasibility of a future RCT to evaluate the effects of the ED exercise intervention on return to work outcomes, health care utilization, and cost-effectiveness in comparison to usual care.

The investigators hypothesize that an exercise intervention in the ED will improve pain, function, global rating of change, and patient satisfaction in comparison to usual ED care with no difference in adverse effects.

Design: A randomized controlled trial (RCT) with two parallel arms (exercise and usual care).

Blinding: The patient will be partially blinded by our not providing full details on the two exercise approaches being studied. The health care providers delivering the interventions will not be blinded due to the nature of the intervention. However, research assistants administering the outcome measures will be blinded. The outcomes assessed are objective measures assessed using an online survey tool that will be free of assessor bias.

Randomization and allocation concealment: Participants will be randomized in a 1:1 ratio to exercise or usual care groups by an independent statistician using a computerized random number generator. The random allocation will be placed in sequentially numbered opaque envelopes. The envelopes will be opened by the RA after completion of baseline assessment.

Patient enrollment: Consecutive patients with acute LBP who are seeking urgent care at Kingston General Hospital Emergency Department (ED) and Hotel Dieu Hospital Urgent Care Clinic (UCC) will be invited to participate over a 4-month period May 1 through August 31, 2018). ED based research staff will screen patients for willingness to be invited to participate when they arrive at the ED. These staff will then invite participation once the physician assessment is complete and eligibility criteria are reviewed.

Inclusion criteria: English speaking adults (18-65 years) with recent onset LBP (<1 week).

Exclusion criteria: people with subacute/chronic LBP, previous episode of back pain in the past 3 months, fracture, previous back surgery, red flags (e.g. urinary retention, bilateral or multilevel neurological impairment), traumatic mechanism of injury (fall >3m or 3 steps, MVC >100km/h).

Assessment and outcome measures: All measures will be collected using Qualtrics, a secure online database, at baseline, 48-72 hours, 1-week, 1-month, and 3-months.

Baseline factors used to describe the population: age, gender, duration of back pain (hours), whether there have been previous episodes of back pain, whether or not the participant has pain in other areas of the body, medications, comorbidities, work status prior to onset of back pain, and current work status.

Objective #1: Individual health outcomes will be collected using validated tools described under the outcomes assessed.

Objective #2: This study design will not have adequate power or long-term follow-ups required to adequately evaluate return to work, healthcare use, and cost-effectiveness. The investigators plan to pilot the use of these outcomes to determine the feasibility of conducting a future trial to evaluate these outcomes.

Analysis: For objective #1, Repeated-measure linear mixed models will be used to assess the effect of treatment (exercise versus usual care) on our primary (disability) and secondary (pain, global rating of change, patient satisfaction, adverse effects) outcomes at all time-points (48-72 hours, 1-week, 1- and 3-months). A difference of 2 on the NPRS36 and 3 points on the RMDQ37 will be considered clinically meaningful. For objective #2, all feasibility outcomes will be reported descriptively and analyzed qualitatively as recommended by methods and reporting guidelines for pilot and feasibility studies.

Sample size: The investigators searched one year of ED and UCC records to identify LBP patients eligible for this study. 2000 patients/year attended for back pain with > 500 during our four-month recruitment period. Of these, a chart review suggests 43% of these met our eligibility criteria. Based on past trials in these settings, we expect at least 50% will consent resulting in a sample size of 107+. This will achieve over 90% power to detect a minimally important difference of 3 points on the RMQ, using a two-sided α=0.05 and assuming a standard deviation of 6.2 points and accounting for a 10% loss to follow-up. This will also provide an adequate sample to assess the secondary feasibility objectives.