A Study Of The Effect Of Constraint Induced Movement Therapy On Lower Limb Function After Stroke

Objective:Constraint-induced movement therapy(CIMT)is a novel rehabilitation method for stroke patients,which involves the forced training of the affected limb.It has been confirmed that can effectively improve the patient’s upper limb function.However,the method and effect of lower limb CIMT have high difference.Therefore,the aim of this study is to(1)Investigate the muscle activity forcing characteristics of stroke patients during balance and walking tasks in CIMT environments.(2)Explore the cortical activation forcing characteristics of stroke patients during balance and walking tasks in CIMT environments.(3)Explore the coupling characteristics between lower limb muscle activity and brain activation during balance and walking tasks in stroke patients using CIMT methods.Methods: This study is a case-control research that uses stroke patients and age-matched healthy individuals as the research subjects.Regular balance walking tasks and CIMT-specific balance walking tasks that match them are designed.The real-time detection of the lower limb muscle activation pattern and brain cortex activation pattern during the experimental tasks was carried out using surface electromyography(s EMG)and functional near-infrared spectroscopy(f NIRS).The balance walking tasks include:(1)Non-CIMT task: regular balance reaction and regular walking;(2)CIMT task: the balance reaction standing CIMT forced induction methods include 1)only disturbing the affected foot to induce the affected side step reaction,2)only disturbing the healthy foot to induce sufficient center of gravity transfer toward the affected side during the reaction of stepping toward the healthy side.The CIMT forced induction method for walking tasks includes 1)instability of the healthy shoe,2)instability of the support surface of the affected side;the first method aims to induce a longer stance on the affected side and satisfactory center of gravity transfer when walking,while the second method aims to induce faster swing speed on the affected side.Surface electromyography is used to detect muscles on both sides,including the anterior tibialis muscle and the gastrocnemius muscle.Functional near-infrared spectroscopy is used to detect the interested brain regions,including bilateral supplementary motor area/premotor cortex(SMA/PMC),primary motor area(M1),primary somatosensory area(S1)and somatosensory association cortex(SAC).A factorial repeated measures ANOVA is used to compare the differences in the functional patterns of the cerebral cortex activation and the muscle activation patterns of the affected lower limb induced by different CIMT methods during balance walking tasks,as well as the differences between stroke patients and healthy individuals during regular tasks.Pearson correlation analysis is used to compare the correlation between lower limb muscle activity and brain activation.Results:1.CIMT balance(1)The muscle activity was only influenced by groups,the both side gastrocnemius muscle and unaffected side bilateral tibialis anterior of the stroke shows significantly higher than the healthy group.(2)The brain activation was influenced by groups and tasks,the healthy side disturbed step balance reaction is the highest among these tasks and the SMA,M1,S1 and SAC brain area of the stroke shows significantly lower than the healthy group.(3)The correlation between muscle activity and brain region activation: There is a negative correlation between the muscle activity and brain area of the affected-side disturbed step balance reaction,while there is a positive correlation for the unaffected side disturbed step balance reaction.2.CIMT walking(1)The muscle activity was only influenced by groups,affected side bilateral tibialis anterior and the unaffected side gastrocnemius muscle of the stroke shows significantly higher than the healthy group.(2)The brain activation cannot be influenced by groups,tasks and the interactive effect of these influence factors.(3)Wearing unstable shoes in unaffected side for walking shows a significant positive correlation(P<0.05)between the affected side gastrocnemius muscle and brain area.Conclusion:(1)In a balanced reaction,only the agile and disturbed step reactions can fully mobilize the activation of the patient’s motor and somatosensory brain regions,and there is a positive correlation between muscle activity and brain region activation.It is recommended for specific CIMT balance reaction training.(2)The two types of CIMT walking cannot fully mobilize the muscle activity and brain region activation of stroke patients,and cannot produce a good forced induction effect.Thus,they can be used for the expansion of rehabilitation training programs.