RELIABILITY OF AN OPTOELECTRIC SYSTEM TO MEASURE ELBOW KINEMATICS

Motion analysis of the upper extremity during functional activities ha s only recently become more accessible. An optoelectric system (WATSMA RT) was subjected to testing using first a calibration dummy and then human subjects. The mean differences between the system calculated ang les and those measured with potentiometers on a calibration dummy were less than 1.6-degrees in all three planes. The test-retest reliabilit y of the system when measuring elbow motion of human subjects yielded acceptable repeatability for measurement of functional activities. Cal culation of the least significant difference found that minimum differ ences from 4 to 14-degrees in flexion and from 10 to 19-degrees in rot ation can be detected using the reported set-up and protocol.