REPRODUCIBILITY OF EMG SIGNALS AND GAIT ANALYSIS DATA INTHE HIP SURROUNDING MUSCULATURE

Abstract

973 The reproducibility of measurements is a problem which recurs constantly in the application of electromyography and gait analysis, but which is frequently ignored. Many scientific studies which address the repetitiveness of measuring methods are, moreover, incorrectly interpreted, usually due to a confusing correlation coefficient. For this reason, this study determined the reporducibility of EMG signals (surface EMG, NORAXON) of the surrounding muscles (M. glutaeus med; M. adductor magn.) during isokinetic measuring methods in the hip joint and gait analysis data (ultrasoundtopometric device, ZEBRIS) according to the statistical method described by BLAND and ALTMANN(Lancet 1986). In this study, 15 woman and men between 45 and 68 years of age underwent isometric, concentric and eccentric muscle exercise in a test-retest procedure using isokinetic LIDO-ACTIVE equipment with EMG-measurement and a gait test on teadmill. The reproducibility of EMG signals during strength measurements must be rated unsatisfactory, since adequate reproducibility is given only in abduction/adduction movements in concentric mode, not in isometric and eccentric mode. The fixation of the probands on the isokinetic device is the main problem, also the replacement of the EMG-electrodes. The results of the gait data show generally satisfactory reproducibility, especially for the stance phase and the hip and knee angle.