Sequential Measurements of Muscle Strength by a Hand Held Dynamometer

-Utility of the Sum of 3 Isometric Strengths for Patients with Polymyositis/Dermatomyositis-

Abstract

In this study, using a self-invented hand-held dynamometer we sequentially measured three isometric strengths, neck flexion, shoulder joint abduction and straight leg raise, of 8 polymyositis patients and 1 dermatomyositis patient (3 men and 6 women, average age 44.8). The sum of the 3 isometric strengths correlated with creatine kinase in every case. Therefore, it was supposed that the sum of the 3 isometric strengths reflects an individual whole body muscle strength. The measurement was performed easily, and the time series results are thought to reflect the disease progress of polymyositis and dermatomyositis. The results suggest that the dynamometer's use in the evaluation of the 3 isometric strengths and the treatment effect in acute rehabilitation would be effective.