Evaluation of the Ability to Maintain a Sitting Position Using a Hand-Held Dynamometer

―The Change with Ageing in Normal Adults―

Abstract

In order to evaluate the ability to maintain a sitting position, we placed a Hand-Held Dynamometer (HHD) on a subjects right or left lateral brachium, pushed it until the subject could not keep the position, and measured the maximum value. We also examined the change with aging and difference between the right and left sides in the value. Subjects consisted of 18 healthy males and 21 healthy females, and they were instructed to sit on a tilt table with the popliteal region apart from the edge of the table and without the feet touching the floor. They were also asked to cross the upper extremities in front of the trunk, and to keep the trunk as upright as possible. A sitting surface was set flat, and tilted by 10 degrees on the right or left side. We continued to push HHD until a subjects ischial bone leaves from the sitting surface, and each measurement was randomly undertaken. It was found that the maximum value of HHD tended to become small with aging, and that subjects aged from 60 to 80 years are liable to show the difference between the right and left sides when pushed from tilted side. The results suggest a possible application of the present method to the evaluation of the ability to maintain a sitting position in the elderly, by comparing the values on a flat surface with those on a tilted surface.