Effects of spinal manipulation on sensorimotor function in low back pain patients - A randomised controlled trial

Background: Low back pain (LBP) is a major health problem in industrialized societies. Spinal manipulation (SM) is often used for treating LBP, though the therapeutic mechanisms remain elusive. Research suggests that sensorimotor changes may be involved in LBP. It is hypothesized that SM may generate its beneficial effects by affecting sensorimotor functions. Objectives: To compare changes in sensorimotor function, as measured by postural sway and response to sudden load, in LBP patients following the delivery of high-velocity low amplitude (HVLA)-SM or low-velocity variable amplitude (LVVA)-SM versus a sham control intervention. Design: A three-arm (1: 1: 1 ratio) randomized controlled trial. Methods: A total of 221 participants who were between 21 and 65 years, having LBP intensity (numerical rating scale) >4 at either phone screen or the first baseline visit and >2 at phone screen and both baseline visits, and Quebec Task Force diagnostic classifications of 1, 2, 3 or 7 were enrolled to receive four SM treatments over two weeks. Study outcomes were measured at the first and fifth visits with the examiners blinded from participant group assignment. Results: The LVVA-SM group demonstrated a significant increase in medial-to-lateral postural excursion on the soft surface at the first visit when compared to the control group. No other significant between-group differences were found for the two sensorimotor tests, whether during the first visit or over two weeks. Conclusions: It appears that short-term SM does not affect the sensorimotor functions as measured by postural sway and response to sudden load in this study. (C) 2015 Elsevier Ltd. All rights reserved.