TEST-RETEST RELIABILITY OF ECCENTRIC PEAK TORQUE VALUES FOR SHOULDER MEDIAL AND LATERAL ROTATION USING THE BIODEX ISOKINETIC DYNAMOMETER

In order for the Biodex isokinetic dynamometer to be used in clinical research, it must be documented to be a reliable measurement tool. The purpose of this study was to determine eccentric peak torque test-ret est reliability for glenohumeral medial and lateral rotator muscles us ing the Biodex isokinetic dynamometer. Eighteen healthy men and women volunteers ranging in ages from 18 to 30 who exhibited no prior histor y of glenohumeral injury were studied. The subjects were tested bilate rally for eccentric glenohumeral medial rotation (MR) and lateral rota tion (LR) at 90 and 120-degrees/sec using 0-degrees of shoulder abduct ion so that the subject's arm was in contact with his or her trunk. Se ven days following the initial test, a retest was administered using t he identical protocol. Data collection of pretesting and posttesting w as done using the IBM basic computer and the Biodex software program. Test data were analyzed using the intraclass correlation coefficient. The test-retest results indicated: dominant LR at 90-degrees/sec, r = 0.86, and at 120-degrees/sec, r = 0.83; dominant MR at 90-degrees/sec, r = 0.76, and at 120-degrees/sec, r = 0.77, nondominant LR at 90-degr ees/sec, r = 0.76, and at 120-degrees/sec, r = 0.83; and nondominant M R at 90-degrees/sec, r = 0.75, and at 120-degrees/sec, r = 0.83. The r esults demonstrate the isokinetic eccentric mode of the Biodex dynamom eter to be reliable for the test-retest measure of peak torque. These data may be used to support future clinical research of the eccentric isokinetic mode of the Biodex isokinetic dynamometer.