The aim of this investigation was to evaluate the objectivity of pendulum test for quantitative measurement of spasticity performed with the Cybex Ⅱ+ isokinetic Dynamometer. The spasticity was assessed in the knee extensors in twenty normal subjects and fifteen spastic hemiplegic patients. Four parameters were extracted from goniogram:
1) Relaxation index in supine position was 1.36±0.06 in normal, 1.15±0.08 in spastic side, 1.36±0.09 in unaffected side and in sitting position, 1.32±0.06 in normal, 1.23±0.06 in spastic side, 1.32±0.09 in unaffected side. The values in spastic side were significantly lower compared with those of normal and unaffected side. And the five sequential tests with repeated trials proved that the between-trial variances were not significant.
2) Amplitude ratio in supine position was 1.87±0.20 in normal, 1.45±0.18 in spastic side, 1.89±0.30 in unaffected side and in sitting position 1.79±0.24 in normal, 1.55±0.17 in spastic side, 1.75±0.24 in unaffected side. The ratio showed significant decrease in spastic side, however demonstrated that the range of distribution was more widening than relaxation index.
3) The number of swing and swing time were not different statistically between normal subjects and spastic patients.
It can be proposed that the pendulum test using a Cybex Ⅱ+ Dynamometer is a objective and clinically applicable method for evaluating spasticity with relaxation index and amplitude ratio, furthermore the relaxation index in supine position is the more effective parameter for quantitative measurement of the spasticity.
