Estimation of Motor Recovery using Characteristics of EMG during Isometric Muscle Contraction in Hemiparetic Wrist

  • Tae, Ki-Sik (Dept. of Biomedical Engineering, Konyang University) ;
  • Song, Sung-Jae (Dept. of Mechanical Engineering, Kangnung University) ;
  • Kim, Young-Ho (Dept. of Biomedical Engineering, Yonsei University)
  • Published : 2008.02.29


The aim of this study was to evaluate the motor recovery in 4 chronic hemiparetic patients with Fugl-Meyer (FM) and EMG characteristics before and after the training program. The training was performed at 1hr/day, 5days/week during 6 weeks in 4 chronic stroke patients. Electromyographic activities of the affected hand were recorded during isometric wrist flexion/ extension movements. In all patients, FM was significantly improved after the 6-week training. Onset/offset delay of muscle contraction significantly decreased in the affected wrist after the training. The co-contraction ratio of flexor/extensor muscles decreased significantly. Also, onset/offset delay of muscle contraction and co-contraction ratio correlates significantly with upper limb motor impairment and motor recovery. This EMG technique allows an objective evaluation of changes in muscle activity in post-stroke patients, providing easily measurable, quantitative indices of muscle characteristics.


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