- The purpose of this study was to examine the use of a hand-held dynamometer in measuring the effect of short-leg tone reducing casts (STRC) on the compliance of calf muscles to passive stretch in CP children and to assess the reliability of this technique in terms of intertester agreement. STRCs were fitted to thirteen children suffering from CP for a period of three weeks. Three measurements were taken independently by two physical therapists: before casting, immediately after cast removal, and one month later. Each child was measured twice: in prone and supine positions. There was a significant (p < 0.01) increase in muscle compliance immediately after removing the casts, but the overall effect tended to diminish after one month. Intertester agreement was high as shown by intraclass correlation coefficients, which ranged from 0.89 to 0.95, thus supporting the application of this technique for assessing the status and variations of passive muscle compliance in CP children.