Simulation And Research On Gait Dynamics Of Spastic Hemiplegia With Small Sample Size

Purpose:The mechanical analysis of the gait of the lower extremity spastic hemiplegia after a small sample of stroke was carried out.Through the comparison with the relative mechanical indexes of the normal gait,the kinematics and dynamics characteristics of the stroke spastic hemiplegic gait were statistically analyzed.This provides a reference for follow-up rehabilitation training of walking ability for patients with stroke spastic hemiplegia,which can speed up the rehabilitation process and improve the efficiency of rehabilitation.Methods:30 post-stroke patients with spastic hemiplegia paste 78 marker points,use Vicon 3D motion capture system to collect their gait kinematics data,select 35 marker points data for basic arrangement and Visual Basic data conversion,Imported Lifemod human dynamics modeling software to establish a musculoskeletal model of spastic hemiplegia gait.After model screening and preliminary data analysis,15 cases of human walking dynamics models that meet the requirements were selected.Through Lifemod software analysis and calculation,the corresponding joint motion angle,joint torque,ground reaction force and muscle strength of the 17 muscles of the lower limbs are obtained,and the relevant parameters of normal people are statistically compared and analyzed.Results:1.The stride length and speed of the affected side and the uninfected side of hemiplegia patients are significantly reduced,and the proportion of double supports is significantly extended;the single support of the affected side is lower than the normal value,and the proportion of the uninfected side is much higher than the normal gait.2.The ankle joint on the affected side of hemiplegia lacks dorsiflexion movement,only in the swing phase dorsiflexion is less than the normal range(P<0.05),and the plantar flexion angle is less than the normal value(P<0.05)in the early stage of support and during the swing phase;sagittal plane The impulse moment of the internally affected ankle joint is less than the normal value.In some patients,only ankle joint valgus occurred,and the valgus angle was larger than that of normal people(P<0.05);patients with only varus motion had severe varus.3.The flexion angle of the affected knee joint in the support phase is greater than the normal value(P<0.05),showing abnormal flexion,and the difference in the swing phase is not significant(P>0.05);the extension angle of the affected knee joint is only greater in the end of the support phase Normal value(P<0.05),no significant difference in other phases(P>0.05).4.In spastic hemiplegia,the range of flexion and extension of the hip joint in the early,middle and swing stages of support was smaller than the normal value(P<0.05);the impulse moment of the affected side was smaller than the normal value.Patients with only adduction movement had excessive adduction in the early and late stages of support(P<0.05).In patients with both abduction and adduction,the adduction angle in the mid-support phase and swing phase was less than the normal value(P<0.05).Except for the peak abduction angle of the affected side in the end-support phase,the peak value was significantly greater than the normal value.The peak values of the spread were significantly smaller than the normal peak values.5.In the 15 samples,the overall GRF trend of the affected side of hemiplegia showed a relatively unsmooth double-peak curve,and the curve of the healthy side changed smoothly in the middle and end stages of support;the first and second peaks and normal values of the healthy and affected side of hemiplegia The difference is not much,the first peak of the affected side is delayed by about 10%of the gait cycle than the normal gait.6.The gastrocnemius muscle has insufficient muscle strength in other phases except the mid-support phase.The muscle strength of the tibialis anterior muscle in the mid-support phase and swing phase is lower than normal(P<0.05),and the soleus muscle strength level in the mid-and end-support phases Lower(P<0.05).7.From the beginning of single support to the end of the gait cycle,the muscle strength of the rectus femoris is significantly lower than the normal value.There was a significant difference between the short head of the biceps femoris and the biceps femoris at the end of support and swing phase(P<0.05);the strength of the long head of the biceps femoris was generally low in the gait cycle,and the internal femoris and semitendinosus muscles.The difference is small and can be ignored.8.Rectus femoris,as a double-joint muscle,has the same muscle strength level as the knee joint;iliopsoas muscle,gluteus maximus 2,adductor maximus,and gluteus medius 1 are generally lower than normal during the gait cycle(P<0.05);gluteus maximus muscles 1 and 2 only have peak muscle strength lower than normal in the swing phase(P<0.05).Conclusions:Comprehensive analysis shows that for patients with spastic hemiplegia,rehabilitation training of related muscles should be carried out according to different stages of walking.1.Insufficient dorsiflexion of the affected ankle joint in the early stage of support is caused by insufficient muscle strength of the lateral head of gastrocnemius and anterior tibialis;in the middle stage of support(single support of the affected side),the muscle strength training of comparative soleus should be strengthened;improving the muscle strength level of triceps crus and anterior tibialis can improve the abnormal varus and valgus of ankle joint.2.The spasm of rectus femoris in swing phase is the main cause of insufficient knee extension;the contracture and insufficient muscle strength of biceps femoris in support phase lead to excessive flexion of knee joint,and the muscle strength of rectus femoris decreases,so the knee joint loses the main source of knee extension power,which reversely aggravates the abnormal flexion of joint.3.For the patients with abnormal adduction abduction of hip,the rehabilitation training of adductor maximus and gluteus medius near femur can be strengthened,while the lower part of gluteus maximus and gluteus medius near sacrum have little effect on hip joint movement of patients with spastic hemiplegia.