The effect of the stay active advice on physical activity and on the course of acute severe low back pain

BACKGROUND Disability due to acute low back pain (ALBP) runs parallel with distress and physical inactivity. If low back pain persists, this may lead to long-term sick leave and chronic back pain. This prospective randomized study evaluated the effect on physical activity and on the course of ALBP of two different treatment advices provided in routine care. METHODS Ninety-nine patients with acute severe LBP examined within 48 h after pain onset were randomized to the treatment advices "Stay active in spite of pain" (stay active group) or "Adjust activity to the pain" (adjust activity group). Pedometer step count and pain intensity (Numeric Rating Scale, NRS, 0-10) were followed daily during seven days. Linear mixed modeling were employed for statistical analyses. RESULTS The step count change trajectory showed a curvilinear shape with a steep initial increase reaching a plateau after day 3 in both groups, followed by an additional increase to day 7 in the stay active group only. At day 1, the step count was 4560 in the stay active group compared to 4317 in adjust activity group (p = 0.76). Although there were no statistical differences between the two groups in the parameters describing the change trajectory for step count, the increase in step count was larger in the stay active group. At day 7 the step count was 9865 in the stay active group compared to 6609 in the adjust activity group (p = 0.008). The pain intensity (NRS) trajectory was similar in the two groups. Between day 1 and day 7 it decreased linearly from 5.0 to 2.8 in the stay active group (p < 0.001), and from 4.8 to 2.3 in the adjust activity group (p < 0.001). CONCLUSIONS Patients with acute severe LBP advised to stay active in spite of the pain exhibited a considerable more active behavior compared to patients adjusting their activity to pain. This result confirms compliance to the treatment advice as well as the utility of the stay active advice to promote additional physical activity for more health benefits in patients with ALBP. There was minimal effect of the treatment advice on the course of ALBP. TRIAL REGISTRATION ClinicalTrials.gov (NCT02517762).