A Development of Measurement System of Elbow Joint for Spasticity by Using Motor

Abstract

There is a spasticity in symptom that stroke hemiplegia patients usually develop. In addition to stroke, the spasticity is developed by head injury and spinal cord injury. The spasticity occurs mainly in limbs such as fingers, elbows, and ankles. Then patients cannot move their limbs as the symptom. Activity of Daily Living (ADL) is influenced by the symptom in their daily life. Therefore, it is important to evaluate the spasticity. Modified Ashworth Scale (MAS) and Modified Tardieu Scale (MTS) are mainly used as the evaluation method of the spasticity. However, each evaluation method is a manual test by an examiner. Therefore, the evaluation is not reliable because the experience, intuition, and subjectivity of the examiner influence the evaluation. In this study, we develop a measurement system for spasticity. First, we use the motor to flex the right arm of subjects. Next, we measure reaction forces and angles in flexion. Experiments perform in the normal state and the spastic state. In the normal state, subjects apply no force. In the spastic state, subjects apply the force at around 45 degrees. The flexion speeds are 1 rpm, 2 rpm, 3 rpm and 4 rpm. We perform the measurement between 0 degrees to 90 degrees in all the experiments. In this experiment, three healthy adult men participated. First, we performed normal experiment three times with four speeds. Next, we performed spasticity experiment with same way. We analyzed kurtosis and skewness to evaluate the obtained data. We can measure the spasticity by measuring the dynamic pattern of the reaction forces and angles, and, confirm changes in kurtosis and skewness in four flexion speeds. However, we found many improvements such as arm length and flexion speed. In the future, we will measure real patients.