The Quantitative Measurement of Spasticity Using Change of Muscle Length during Pendulum Test

OBJECTIVE: The aim of this study was to develop objective evaluation method of spasticity which reflects the characteristics of lengthening velocity-dependent stretch reflex of spasticity. METHOD: Kinematic analysis for knee angle and rectus femoris muscle lengthening parameters, and dynamic EMG were performed simultaneously during pendular movement of spastic lower leg for thirty two patients with spasticity and ten normal control subjects. Angular parameters consist of angular relaxation index (ARI), maximal angular velocity (MAV), angular threshold (AT) and angular velocity threshold (AVT). And lengthening parameters consist of lengthening relaxation index (LRI), maximal lengthening velocity (MLV), lengthening threshold (LT) and lengthening velocity threshold (LVT). RESULTS: 1) ARI, MAV, AT, and AVT according to Modified Ashworth scale (MAS) were 1.32+/-0.11, 303.84+/-45.11 deg/sec, 44.19+/-13.81 deg, 262.15+/-33.54 deg/sec in MAS I, 1.16+/-0.16, 279.92+/-42.94 deg/sec, 30.33+/-6.02 deg, 247.65+/-35.92 deg/sec in MAS II, and 0.95+/-0.14, 241.31+/-19.98 deg/sec, 20.55+/-2.68 deg, 209.11+/-48.11 deg/sec in MAS III (P<0.05). 2) LRI, MLV, LT, and LVT according to MAS were 1.27+/-0.11, 0.58+/-0.07, 1.164+/-0.14, 0.53+/-0.05 in MAS I, 1.12+/-0.09, 0.53+/-0.05, 1.150+/-0.08, 0.42+/-0.04 in MAS II, and 0.99+/-0.10, 0.44+/-0.01, 1.137+/-0.15, 0.36+/-0.02 in MAS III (P<0.05). 3) There were significant correlation between various pendulum test parameters and MAS. CONCLUSION: Muscle lengthening parameters as well as knee angular parameters were sensitive parameters reflecting the degree of spasticity. LVT is the most sensitive parameter among all parameters (p<0.01).

Effect of Clonidine on Spasticity in Patients with Spinal Cord Injury

OBJECTIVE: Spasticity has been reported to be one of the common complications in patients with spinal cord injury. The purposes of this study were to investigate the proper dosage, the therapeutic and undesirable effects of clonidine with combined used of baclofen for the management of spasticity. METHOD: A prospective study was performed for 17 patients with spinal cord injury who did not improve spasticity with 80 mg baclofen administration. The degree of spasticity was assessed in the more-affected knee by modified Ashworth scale, pendulum test at pre-treatment and at 7 days after receiving clonidine. We also investigated the complications and subjective satisfaction. RESULTS: Seven of 13 patients with spinal cord injury showed subjective improvement in spasticity. We found significant improvement in the relaxation index by pendulum test after administration of more than 0.3 mg of clonidine. There was no significant difference between the subgroups depending on the extent of spinal cord injury. We didn't find any serious complication in adjuvant clonidine therapy. CONCLUSION: Adjuvant clonidine therapy can be effective in spasticity of spinal cord injured patients without serious complication.

An Evaluation of Spasticity Using Pendulum Test and Dynamic Electromyography

OBJECTIVE: The aim of this study was to develop objective evaluation method which reflect the velocity dependent increase of stretch reflex in spasticity using the pendulum test and dynamic electromyography. METHOD: Kinematic analysis for knee angle and angular velocity measurement, and dynamic electromyography were performed simultaneously during pendulum movement of spastic lower extremity in supine position for nineteen spastic hemiplegia patients and ten normal control subjects. Angular relaxation index (ARI), Maximum angular velocity (MAV), Angular threshold (AT) and Angular velocity threshold (AVT) were used for the evaluation of spsticity. RESULTS: 1) ARI was 1.64+/-0.04 in normal, 1.28+/-0.14 in modified Ashworth scale (MAS) I, 1.18+/-0.16 in MAS II, 1.02+/-0.13 in MAS III, 2) MAV was 325.0+/-29.4 in normal, 301.7+/-37.8 in MAS I, 269.2+/-29.7 in MAS II, 232.4+/-28.2 in MAS III, 3) In normal subjects EMG activity did not occur, whereas in spastic hemiplegic patient a stretch reflex appears in thigh muscle. AT and AVT were 57.39+/-4.45, 256.24+/-14.07 in MAS I, 38.59+/-4.26, 184.45+/-12.7 in MAS II, 19.13+/-7.13, 136.06+/-12.88 in MAS III, respectively, 4) Correlation coefficients of the ARI (r= 0.786), AT (r= 0.960), AVT (r= 0.949) showed significantly negative correlations with the MAS. CONCLUSION: 1) AT and AVT are more sensitive parameters than ARI for documenting spasticity in hemiplegic patients. 2) An evaluation of spasticity using pendulum test and dynamic electromyography would provide consistent results with little error and would not be influenced by the change of examiner or environment. Thus we can get very reliable results using this method.

Pendulum Test Using Video-Based Two Dimensional Motion Analysis Program

The pendulum test, recognized as a reliable measure of spasticity, has been replaced in this study by a video-based two dimensional motion analysis system. Using twenty five patients with spasticity(21 males, 4 females; mean age 46.6 year-old) in their lower legs due to lesions affecting the central nervous system and twenty two persons without any evidence of hypertonia(all males; mean age 23.4 year-old), five parameters such as relaxation index(RI), amplitude ratio(AR), torque at maximal acceleration velocity, number of swing and swing time were obtained for the purpose of documenting the reliability of the video-based two dimensional motion analysis system for the evaluation of spasticity. The values of RI(P<0.05), AR(P<0.01), and swing time(P<0.05) in patients with spasticity were significantly lower than control, whereas the value of torque in patients was significantly higher than control(P<0.01). Spearman's correlation coefficients of the RI(r=+/-0.70894, P<0.001), AR(r=+/-0.71832, P<0.001), number of swing(r=+/-0.59037, P<0.05) and swing time(r=+/-0.59648, P<0.01) showed a statistically significant negative correlation with the modified Ashworth scale, whereas that of torque(r=0.59037, P<0.01) showed a significant positive correlation. In conclusion, a pendulum test using a video-based two dimensional motion analysis system is a simple, and a reliable method for the quantitative evaluation of spasticity.