Design and validation of an instrument package designed to increase the reliability of ankle range of motion measurements.

OBJECTIVE To validate a novel device termed the equinometer, which is designed to accurately measure ankle dorsiflexion. DESIGN Test retest reliability analysis using serial measurements of dorsiflexion endpoint in a group of normal individuals. SETTING Motion analysis laboratory. PARTICIPANTS Ten healthy individuals. PRIMARY OUTCOME MEASURE The mean and standard deviation of the absolute difference in dorsiflexion endpoint for the group. RESULTS The mean absolute change in dorsiflexion endpoint for the group was 0.45 degrees with a standard deviation of 0.43 degrees. CONCLUSIONS With the use of the device described, the mean change in dorsiflexion endpoint was well within acceptable clinical limits. The reliability of measurements obtained with the equinometer exceeds that which has been published with other techniques and devices.