Immediate Effects of Lumbosacral Orthosis on Postural Stability in Patients with Low Back Pain: A Preliminary Study

Lumbosacral orthosis (LSO) is commonly used for the treatment of back pain. The clinical and mechanical effectiveness of this device has been repeatedly investigated in several studies; however, its sensorimotor effectiveness has been rarely considered. Regarding this, the aim of the current study was to investigate the effect of a non-extensible LSO on postural stability (as a construct of sensorimotor function) in patients with nonspecific chronic low back pain (LBP).

This preliminary study was conducted on 17 patients with nonspecific chronic LBP using a single-group quasi-experimental design. Postural stability was measured while the participants were placed in a quiet standing position, under the combined conditions of base of support (rigid and foam surface), visual input (open eyes and closed eyes), and LSO (with and without orthosis).

The findings demonstrated that wearing orthosis during the most challenging postural task (i.e., blindfolded while standing on a foam surface) significantly reduced postural sway parameters related to the position and displacement of the center of pressure (COP; the sway area and sway amplitude in the anteroposterior direction; P<0.001). However, the use of this device had no significant effect on COP velocity.

As the findings of the present study indicated, the use of a non-extensible LSO decreased the COP displacement; however, it did not affect the COP velocity. Therefore, our data could not utterly support the effectiveness of non-extensible LSO on postural stability as a construct of sensorimotor function. Postural control is an appropriate indicator for assessing the global functioning of the sensorimotor system due to its dependence upon the interaction between the neural and musculoskeletal systems. Consequently, further studies are needed to elucidate the positive effects of LSO on the aspects of sensorimotor function.