Hand-Held Dynamometry in Persons with Tetraplegia

Abstract
To compare make and break techniques for hand-held dynamometry in persons with tetraplegia. We compared the interrater and intrarater reliability, the relative forces, and variability between examiner techniques. Two examiners with no previous hand-held dynamometry training performed hand-held dynamometry on the elbow flexors or extensors of 19 persons with upper limb weakness secondary to tetraplegia, using break and make techniques. Testing was performed in two sessions separated by 10 mins. Simultaneous recording from an electrogoniometer placed across the elbow was obtained for a subset of participants. Break and make techniques both showed intraclass correlation coefficients exceeding 0.9 for interrater and intrarater reliability. The maximum expected difference for 95% of repeated measurements was 3.5 kg, with hand-held dynamometry strength values that averaged 7-11 kg. Average break/make ratios ranged from 1.38 +/- 0.29 to 1.49 +/- 0.37. The electrogoniometric data showed that the two examiners used similar testing technique, and small variations in technique were not associated with significant differences in strength recordings. Make and break techniques for hand-held dynamometry both show high reliability over a short intersession period when performed by inexperienced examiners on weak elbow flexors and extensors.