Reliability of a Functional Clinical Test Battery Evaluating Postural Control, Proprioception and Trunk Muscle Activity

Abstract

The purpose of this study was to examine the repeatability and reproducibility of the different tests of a clinical test battery evaluating the components of functional spinal stability: postural control (sway velocity data), proprioception (repositioning error), and muscle activation (electromyographic data). A total of 28 healthy volunteers participated in this study: 14 in the repeatability study and 14 in the reproducibility study. Each subject was tested three times, with an interval of 1 wk between the test sessions. The intraclass correlation coefficients and the standard error of the measurements as a percentage of the grand mean were calculated. The intraclass correlation coefficients for both the repeatability and the reproducibility evaluation showed good to excellent reliability for all variables (intraclass correlation coefficient, 0.60-0.98). The standard error of the measurements as a percentage of the grand mean ranged from 0.004 to 19.94. The functional clinical test battery investigated in this study proved to be a reliable tool in the assessment of healthy subjects. The evaluation of postural control, proprioception, and muscle activity (coordination, stabilization, maximal voluntary isometric contraction, endurance, and flexion-relaxation) showed good to excellent repeatability and reproducibility. Further analysis of the reliability of these variables in a clinical setting, particularly in patients with low back pain, seems appropriate.