VISUAL DEPENDENCE AND POSTURAL SWAY CHANGES AFTER MILD TRAUMATIC BRAIN INJURY: A SENSOR PLATE BASED OBSERVATIONAL STUDY

Abstract

Background
Mild traumatic brain injury frequently produces dizziness, unsteadiness and reduced balance confidence even when
routine clinical examination appears almost normal. Postural control depends on the coordinated use of visual,
vestibular and somatosensory information. After mild traumatic brain injury, patients may compensate by depending
excessively on visual input. This visual dependence becomes more evident when balance is examined under eyes-
closed conditions using sensor plate analysis.
Objective
To assess visual dependence and postural sway changes in patients with mild traumatic brain injury using sensor
plate analysis, and to examine the association of sway findings with Berg Balance Scale score and dizziness severity.
Methods
A prospective observational study was conducted among 60 participants diagnosed with mild traumatic brain injury
in the subacute phase. Participants were assessed using the Berg Balance Scale and sensor plate analysis. Sensor plate
testing was performed during quiet standing in eyes-open and eyes-closed conditions for 30 seconds, repeated over
three trials. Mean sway area and EC/EO ratio were used to describe postural instability and visual dependence.
Descriptive statistics, paired t-test, Pearson correlation and McNemar test were used for analysis with significance set
at p < 0.05.
Results
The mean age of participants was 32.82 +/- 8.07 years. Mean Berg Balance Scale score was 49.08 +/- 3.03,
suggesting near-normal functional balance. Sensor plate analysis showed mean eyes-open sway of 275.42 +/- 68.91
mm² and mean eyes-closed sway of 470.07 +/- 101.40 mm². Eyes-closed sway was significantly higher than eyes-
open sway (paired t = 37.566, p = 0.0000), and the mean EC/EO ratio was 1.73 +/- 0.13. Sensor plate analysis
detected balance impairment in 44 participants, whereas BBS detected impairment in only 4 participants. Eyes-closed
sway showed a significant positive correlation with dizziness severity (r = 0.288, p = 0.0258).
Conclusion
The findings suggest that patients with mild traumatic brain injury demonstrate increased visual dependence and
greater postural sway when visual input is removed. Sensor plate analysis is useful for identifying hidden postural
instability that may not be fully detected through functional balance scoring alone. The EC/EO sway ratio may
provide clinically meaningful information for planning vestibular, proprioceptive and sensory integration based
rehabilitation.