The Research Of Surface Electromyography Of Lower Extremity Muscles In Stroke Patients

Objective: Hemiplegic stroke was caused by the upper motor neuron disease,which performance of the injury level of the distal extent was seriously than the proximal and the limbs stronger than the trunk limbs. In recent years,scholars have found that maximum isometric voluntary contraction of ankle dorsiflexors and plantarflexors comparison of surface electromyography between patients at the acute stage after stroke and age-matched healthy elder . In the normal activities of the ankle(including ankle dorsiflexors and plantarflexors ) dorsiflexors muscles (mainly anterior tibial muscle) plays an important role and there was no significant difference in both sides .The affected side of strokes patients compared with the ankle and their contralateral or the healthy elderly and muscle function were significantly reduced eases. particularly in the tibial muscle contraction weakened more obvious.Contralateral limb is not normal, the gastrocnemius muscle contractility increase synergy.In addition to the above on the lower extremities in patients with hemiplegia synergistic muscle contraction studies, for no other aspects of the study .The testing on the surface EMG collection ankle dorsiflexors and plantarflexors sEMG signal. Specific studies on patients with hemiplegia recovery of anterior tibial muscle and gastrocnemius muscle.Reveal to change its mechanism and clinical significance is the main purpose of this experiment.Subjects and methods: 30 strokes and 9 normals are involved in this study. Before test, all the patients accept measurement of the ankle angle. Dorsiflexors ankle will be 0-10 degrees (includ 10 degrees) as heavy foot-drop group and ankle dorsiflexion angle of 10-20 degrees as light foot-drop group, We choose 9 normals as controls.We use DNI-200P EMG machine and Ag-Agcl surface electrodes. Deal with the skin carefully when place electrodes and the EMG signals of bilateral anterior tibial muscles and gastrocnemius muscle. Testing was tested supine position, both feet on a specially designed frame to maintain a neutral position ankle, knee maintain Extension .Surface electrodes were applied on the skin of both anterior and gastrocnemius muscle for electromyography (EMG). Before the test objects as far as possible relax and no EMG on oscilloscope .Healthy tests left and right test sequence is not fixed, stroke patients each contralateral first test.At the same time test record the average voltage of dorsiflexors and plantarflexors.Use SPSS 11.5 to analyse the data ,use independent t test to analyse the difference within the groups and use one way ANAVO to analys the difference between groups ,the significance is P<0.05,bilateral tested .Results: The standardized data processing.Normal persons bilateral anterior tibial muscle and gastrocnemius muscle EMG no difference (p> 0.05).Contralateral anterior tibial and gastrocnemius muscle of stroke patients with EMG activity and the normal no difference (p> 0.05).The ipsilateral anterior tibial muscle and gastrocnemius muscle of stroke patients regardless light or heavy foot-drop Group EMG activity were lower than the contralateral.Normal persons anterior tibial muscle - gastrocnemius muscle EMG activities, the anterior tibial muscle activity than the gastrocnemius, and the difference was significant (P <0.05).Light foot-drop patients with anterior tibial muscle - gastrocnemius muscle EMG activities, the anterior tibial muscle is strong, and the difference was significant (P <0.05).Heavy foot-drop in patients with anterior tibial muscle group - gastrocnemius muscle EMG activities, the anterior tibial weaker than gastrocnemius muscle, but there was no significant difference (P> 0.05).Conclusion: Contralateral anterior tibial muscle and gastrocnemius muscle of patients EMG activity compared with the normal was no significant difference.Foot-drop side anterior tibial muscle and gastrocnemius muscle of patients EMG activity were lower than the contralateral.Normal persons anterior tibial muscle activity than the gastrocnemius, and the differences are significant.Normal anterior tibial muscle activity than the gastrocnemius, and the differences are significant .Heavy foot-drop patients affected anterior tibial weaker than gastrocnemius muscle activity, but there was no significant difference, functional recovery is poor .In short, the patients with hemiplegia affected limb muscle dysfunction, patients with hemiplegia, the earlier rehabilitation treatment, the better rehabilitation.