An exploration of the use of Inertial Measurement Units in the assessment of dynamic postural control of the knee and the effect of bracing and taping

Abstract

Background: The Star Excursion Balance Test (SEBT) is a common clinical test that can provide information about dynamic movement, but does not reflect movement quality or postural-control strategies, and does not report kinematics of the lower limb.
Purpose: To assess the dynamic postural control of healthy subjects using inertial measurement units (IMUs) and clinical SEBT scores to determine the effect of knee bracing and taping.
Methods: Twenty-four healthy individuals performed the SEBT under three randomised conditions (patellar bracing, patellar taping, and control condition (no intervention). Clinical SEBT scores were recorded and normalised to leg length and angular velocities were measured using IMUs during SEBT. Composite scores were calculated as the sum of clinical scores in each direction divided by three. Descriptive statistics (mean ± sd) were calculated for each variable and repeated measures ANOVA were used to identify differences between limb (dominant, non-dominant) and condition.
Main Results: Compared to the control condition, bracing and taping significantly improved dynamic postural control in the sagittal plane by 6% (1.5-10.5%) P=0.011 and 8% (2.9-13%) P=0.004 respectively. Bracing significantly improved coronal plane stability compared to the control condition by 9% (3.8-14.1%) P=0.002, and taping by 7% (1.6-12.6%) P=0.013. SEBT scores revealed small but statistically significant differences (P<0.05) between conditions in the anterior, posteromedial and composite scores, all showing a difference of between 1-2%.
Principal Conclusions: Patellar soft bracing and taping can improve dynamic postural stability during SEBT. It is possible to detect clinically important changes in lower limb stability from angular velocity using IMUs.