Effects of low back pain and of stabilization or movement-system-impairment treatments on induced postural responses: A planned secondary analysis of a randomised controlled trial.
BACKGROUND
Motor retraining for non-specific chronic low back pain (LBP) often focuses on voluntary postural tasks. This training, however, may not transfer to other known postural impairments, such as automatic postural responses to external perturbations.


OBJECTIVE
To evaluate the extent current treatments of motor retraining ameliorate impaired postural coordination when responding to a perturbation of standing balance.


METHODS
Planned secondary analysis of a prospectively registered (NCT01362049), randomized controlled trial with a blinded assessor.


METHODS
Sixty-eight subjects with chronic, recurrent, non-specific LBP were allocated to perform a postural response task as a secondary assessment one week before and one week after receiving either stabilization or Movement System Impairment (MSI)-directed treatment over 6 weekly 1-h sessions plus home exercises. For assessment, subjects completed the Oswestry disability and numeric pain rating questionnaires and then performed a postural response task of maintaining standing balance in response to 3 trials in each of 4 randomly presented directions of linear surface translations of the platform under the subjects' feet. Integrated amplitudes of surface electromyography (EMG) were recorded bilaterally from the rectus abdominis (RA), internal oblique (IO), and external oblique (EO) muscles during the postural response task.


RESULTS
No significant effects of treatment on EMG responses were evident. Oswestry and numeric pain ratings decreased similarly following both treatments.


CONCLUSIONS
Stabilization and MSI-directed treatments do not affect trunk EMG responses to perturbations of standing balance in people with LBP, suggesting current methods of motor retraining do not sufficiently transfer to tasks of reactive postural control.
Department of Rehabilitation and Movement Science, University of Vermont, 305 Rowell Building, 106 Carrigan Drive, Burlington, VT 05405, USA. Electronic address: jjacobs@uvm.edu.
Jesse V
JV
Jacobs
School of Health Sciences, Central Michigan University, 1179 Health Professions Building, Mount Pleasant, MI 48859, USA. Electronic address: lomon2k@cmich.edu.
Karen V
KV
Lomond
Department of Rehabilitation and Movement Science, University of Vermont, 305 Rowell Building, 106 Carrigan Drive, Burlington, VT 05405, USA. Electronic address: juvena.hitt@uvm.edu.
Juvena R
JR
Hitt
Department of Medical Biostatistics, Hills 23C/25H, 105 Carrigan Drive, University of Vermont, Burlington, VT 05405, USA. Electronic address: Michael.DeSarno@uvm.edu.
Michael J
MJ
DeSarno
Department of Medical Biostatistics, Hills 23C/25H, 105 Carrigan Drive, University of Vermont, Burlington, VT 05405, USA. Electronic address: janice.bunn@uvm.edu.
Janice Y
JY
Bunn
Department of Rehabilitation and Movement Science, University of Vermont, 305 Rowell Building, 106 Carrigan Drive, Burlington, VT 05405, USA. Electronic address: sharon.henry@uvm.edu.
Sharon M
SM
Henry
D000328:Adult; D005081:Exercise Therapy / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D017116:Low Back Pain / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D009068:Movement / Q000502:physiology*; D010147:Pain Measurement / Q000379:methods*; D004856:Postural Balance / Q000502:physiology*; D011446:Prospective Studies; D011795:Surveys and Questionnaires; D016896:Treatment Outcome; D055815:Young Adult
Balance; Low back pain; Movement system impairment; Posture; Stabilization; Treatment