Objective: To find useful parameters in biomechanical assessment of spasticity.

Method: Knee extensor muscles of 60 limbs of 47 patients which showed clinical spasticity were stretched by isokinetic dynamometer. Stretch was done with the velocities of 60^o/sec, 120^o/sec, 180^o/sec, 240^o/sec. Four parameters [torque onset angle (TOA), peak torque angle (PTA), peak eccentric torque (PET), peak eccentric torque area (PETA)] were measured at each stretch velocity. Then, regression analysis was performed in relationship between each parameter and strech velocity. We analysed the correlation between the slope of each parameter in regression equation and clinical Modified Ashworth Scale (MAS).

Results: The slope of TOA and PTA had negative value so that they showed the decreasing trend of their value according to increasing velocity. On the other hand the slope of PET and PETA had positive value which meant that those parameters increased according to increasing velocity. The slope of PET and PETA were correlated statistically. The higher the MAS score was, the larger value of slope of PET, PTEA were noted.

Conclusion: Peak eccentric torque and Peak eccentric torque area are thought to be useful parameters in biomechanical assessment of spasticity. (J Korean Acad Rehab Med 2002; 26: 321-326)

Objective: The purpose of this study was to examine the strength of the knee and pulmonary function comparing collegians and hockey players in college.

Method: KINㆍCOM isokinetic dynamometer and medigraph were used to evaluate strength of the right lower extremity and pulmonary function to 30 male students comprising 15 hockey players and 15 collegians with no significant difference in age, weight, and height between the two groups. All subjects used their right lower limb as dominant limb.

Results: 1) The significant differences between collegians and hockey players were found in the peak torque at 60^o/sec,

180^o/sec. 2) The siginficant differences between collegians and hockey players were found in forced vital capacity, forced expiratory volume in one second and expiratory reserve volume on the pulmonary function. 3) The significant correlation between isokinetic strength and pulmonary function were found in peak torque.

Conclusion: It is turned out that hockey players in college have much better isokinetic strength and pulmonary function than collegians, so it is suggested this result have to be considered in selecting hockey players and exercise prescription. (J Korean Acad Rehab Med 2002; 26: 228-232)

Objective: To analyze the patterns of isokinetic knee torque curves in normal population and determine the characteristics of those curves.

Method: Two hundred and eightly-six normal subjects were included. The isokinetic knee torque curves were divided into three parts; to the angle of peak torque generation, to the point 10∼20 degrees prior to end of joint motion, and to the end of joint motion. Each part was classified as convex(1), flat(2) and concave(3) type according to the shape. The curves were named such as 1-2-2 in order. Types of the curves, peak torque, angle of knee at peak torque, total acceleration energy, age, and sex of the subjects were compared.

Results: For knee extensors, frequencies of the curve types were 1-2-2(A), 1-2-1(B), 1-3-1(C), and 1-3-2(D). Mean ages of type A and B curves were slightly higher than types of C and D. Mean peak torque was greatest in type D. For knee flexors, the frequencies were 1-2-2(A), 1-2-1(B), and 1-1-2(C). Female predominance were found in type B while type C was found mostly in male. Mean peak torque was greatest in type C.

Conclusion: The most common torque curve type was 1-2-2 for knee extensors and flexors. Torque curve types of knee extensors showed differences in age and torque curve types of knee flexors showed differences in sexual distribution.

Objective: We designed this study to evaluate muscle tone by using a biomechanical method and to provide data for the future studies about muscle tone.

Method: We evaluated 29 subjects without known neuromuscalar diseases using the biomechanical method. Both plantar flexors of each subject were passively stretched by isokinetic dynamometer from 30^oplantar flexion position to 10^odorsiflexion position. Peak eccentric torque (PET) and torque threshold angle (TTA) were calculated at angular velocity of 10^o/sec, 90^o/sec and 300^o/sec. Regression lines from torque/position curve at 10^o/sec and 300^o/sec were considered an intrinsic stiffness index (ISI) and total stiffness index (TSI). Stretch reflex threshold speed (SRTS) was defined as the minimum speed of plantar flexion movement in which EMG reflex activity in plantar flexor muscles is induced.

Results: The mean of TTA was higher in 10^o/sec than in 300^o/sec. The means of ISI and TSI were 0.11⁑0.08, and 0.18⁑0.04. The mean of SRTS was 125.2⁑48.3^o. No statistical difference in each parameter was found according to the side or gender.

Conclusion: ISI, TSI, PET, TTA and SRTS using a biomechanical method are thought to be useful parameters for the quantitative assessment of muscle tone change of ankle plantar flexors.

Objectives: The biomechanical assessment of spasticity has been developed recently, but not standardized yet for the test procedures and parameters of measurement. This study was designed for the development of standardized method of the biomechanical assessment of spasticity using the isokinetic dynamometer.

Method: The plantar flexor muscles of both ankles were stretched from 40^o plantar flexion to 20^o dorsiflexion using the isokinetic dynamometer at the angular velocities of 15^o, 30^o, 60^o, 90^o, 120^o, 180^o, and 300^o per second. Three parameters, peak eccentric torque(PET), torque threshold angle(TTA), and angle at peak torque(PTA) were analysed.

Results: PET increased and TTA decreased significantly in the involved side. The side to side difference of PET and TTA increased in the patient group with more spasticity. The side to side difference of PET increased, but the side to side difference of TTA decreased with the increase in the angular velocity.

Conclusions: The isokinetic dynamometer is useful in the assessment of the spasticity of ankle plantar flexor of hemiplegic patients. PET and TTA are useful parameters. The faster angular velocities seemed to be more appropriate for the analysis of torque values and the slower angular velocities seemed to be more appropriate for the analysis of thresholds.