Measurement of the quality of hand contractions

An instrument has been developed which provides quantitative information about hand contractions. The subject must press a rubber balloon for a certain number of times. The information concerning the hand contractions is expressed in terms of certain parameters of the mean pressure time function, which is generated by the hand contractions of the rubber balloon. The parameters are pressure duration, maximum pressure, pressure integral, pressure increase and pressure decrease. The design is based on a hybrid pressure transducer and a microcomputer. The microcomputer controls the course of the measurement and calculates the paramaters at the end. The small size, only four command switches and the six-digit LED display for parameter presentation make the instrument easy for use in the clinic. Experiments made with the instrument (Elektro-Dynamo-Meter) gave significant measurable differences between the parameters of the dominant and the nondominant hand. A comparative study with previous measurements showed slightly more accurate results with the Elektro-Dynamo-Meter.