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Updated: Jan 28, 2026

A Vibrotactile Feedback Device for Seated Balance Assessment and Training
Published on: January 20, 2019
Trunk Control Response to Unstable Seated Posture During Various Feedback Conditions in People with Chronic Low Back
Krista M Cyr, Sara E Wilson, Fahed Mehyar
1University of Kansas Medical Center, Mailstop 2002, 3901 Rainbow Blvd., Kansas City, KS 66160, USA. Tel 913-588-4566, fax 913-588-6910. nsharma@kumc.edu.
Aims:
People with chronic low back pain (CLBP) tend to have altered postural control. Visual biofeedback may be used to restore postural control. The purpose of this pilot study was to investigate the effect of visual biofeedback on seated postural trunk control in subjects with CLBP, and to investigate the relationship between the postural control parameters and clinical tests.
Methods:
Ten CLBP subjects (8 female, 2 male; age 40.6±5 yrs; BMI 25.06±2.93) and 10 healthy matched controls (8 female, 2 male; age 41.2±5.88 yrs; BMI 24.61±3.17) underwent seated postural assessment. Center of pressure (COP) parameters were collected under three experimental conditions: eyes-open, visual biofeedback, and eyes-closed.
Results:
The results revealed that COP velocity was significantly different between healthy and CLBP subjects for each condition, both healthy and CLBP subjects had no differences in COP parameters between eyes-open and visual biofeedback conditions, and in subjects with CLBP, the straight leg raise clinical test had a strong negative correlation with all COP parameters.
Conclusions:
Our results suggest that 30-second visual biofeedback training did not improve the seated postural control of CLBP subjects, potentially due to the short duration of training, and that hamstrings muscle tightness or decreased sciatic nerve mobility was associated with worse postural control.
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