Changes of Gait Characteristics in Stroke Patient with Foot Drop After Treating by Foot Drop Stimulator Combined with Moving Treadmill Training

Background and Purpose To analyze the changes of gait characteristics in stroke patient with foot drop after treating by foot drop stimulator combined with moving treadmill, and provide a basis for the improvement of foot drop gait after stroke. Methods Sixty patients with stroke and hemiplegia with foot drop were randomly divided into the experimental group and the control group. Both groups received basic rehabilitation training. On this basis, the experimental group received foot drop stimulator combined with moving treadmil. The control group received foot drop stimulator training. The treatment time of the two groups was 30 minutes/time, 5 times a week, for 3 consecutive weeks. Gait Watch three-dimensional gait analysis system was used to record the angle of hip exion, knee exion and ankle exion before and after treatment. Results After treatment, the angles of hip exion, knee exion, and ankle exion of the two groups of patients changed, but the above changes in the experimental group were better than those in the control group, The difference is statistically signicant (p<0.05).


Introduction
Foot drooping gait after stroke is very common, with an incidence rate as high as 20%-30%, 1,2 which manifests as ankle joints are not exed or insu ciently exed, showing a cross-threshold gait when walking, affecting walking e ciency. 3,4 This study found that the foot drop stimulator combined with moving treadmill can effectively improve the foot-dropping gait, improve ankle exion, hip exion and knee exion after stroke.
Methods 60 patients with stroke and hemiplegia who were treated in our hospital from January 2019 to March 2020 were selected, divide into the experimental group and the control group with 30 cases each, and the inclusion criteria were: All patients met the diagnostic criteria for stroke in the "2016 Guidelines and Consensus on Diagnosis and Treatment of Chinese Cerebrovascular Diseases", 5  There were no statistical differences in gender, age, disease course, and stroke strati cation between the two groups (Table 1). Connect the main unit and use the walking mode. When the affected leg moves forward, the electrical stimulation is started to stimulate the anterior tibial muscle to produce dorsi exion; when the heel is on the ground, the electrical stimulation is turned off. So that the patient can exion of the foot in time during walking, and the patient's walking is more stable, more natural and safer.
Moving treadmill training (MTT) Moving treadmill training (MTT) is a task-oriented and supportive training. In active treadmill training, the patient walks at a set speed with the help of a at track, just like walking in place, without being affected by space, can exhibit a more symmetrical walking posture.
Gait Watch three-dimensional gait analysis system was used to record the angle of hip exion, knee exion and ankle exion before and after treatment.

Outcomes and statistical analyses
The data obtained before and after the treatment were represented by " ±S", and the SPSS 22.0 statistical software package was used for data analysis. The comparison count data within the group and between groups were tested by χ2, the measurement data were tested by T, and the test level was α=0.05, p<0.05 represented The difference was statistically signi cant.

Results
After 3 weeks of treatment, the angles of hip exion, knee exion, and ankle exion of the two groups of patients all changed, but the above changes in the experimental group were better than those in the control group, and the difference was statistically signi cant (p < 0.05, Table 2)

Discussion
After stroke, the patient is prone to induce abnormal postures such as "circling gait" because of foot drop. Walking in this abnormal exercise mode will hinder the establishment of normal exercise mode and affect the recovery of lower limb motor function in hemiplegia. 6 The ankle joint is the adjustment center of human walking posture and stability. Its dorsi exion function plays an important role in gait. Abnormal dorsi exion function will affect the angle of hip exion and knee exion, resulting in abnormal gait such as sagging. 7 Foot drop after stroke is mainly caused by central nervous system injury. 8 Under normal circumstances, the dorsi exion of the ankle joint is controlled by the common peroneal nerve. There are two branches of the common peroneal nerve, which control the anterior calf muscle group (tibialis anterior muscle) and lateral calf muscle group (long bula and short muscle). The XFT-2001 foot drop stimulator stimulates the tibialis anterior and bula long and short muscles by designing a reasonable and targeted electrical stimulation, causing them to contract, and makes the ankle joint dorsi exed and valgus, thus correcting the foot drop and foot inversion. 9 The correction of foot inversion and foot drop stimulator is helpful for the clearance of the swinging ankle joint during the gait cycle and reducing the body's compensatory posture. 10 The author's previous research results also con rmed that the foot drop walker can effectively improve walking function and lower extremity motor function, reduce the difference between left and right step length, and increase the pace. 11 However, the use of a foot drop walker requires patients to have a certain standing balance and walking ability, and requires a su ciently wide walking training eld, which limits the use of the device.
Moving treadmill training is a task-oriented and supportive training. In the activity at training, the patient walks at the set speed by the at track, just like walking in place, not limited by the venue and space, can be expressed a more symmetrical walking posture to improve walking speed and endurance. 12 Moving treadmill training can solve the patient's lack of balance function and the limitation of the training venue.
In recent years, it has been more used for walking function training. 13,14 However, if the patient has foot drop, when simply using moving treadmill to walk, due to the constant speed of the crawler, it will be prone to sprained ankle.
In this study, the foot drop stimulator combined with Moving treadmill training made up for the shortcomings of the two methods above, and fully showed their respective advantages. The results of the study showed that after treatment, the experimental group's angles of hip exion, knee exion, and ankle exion in the affected side changed signi cantly during the gait cycle. After treatment, the ankle dorsi exion angle increased (p < 0.001), indicating that the motor function of the tibialis anterior muscle was restored and the muscle strength was enhanced, which was bene ted from the stimulation effect of the foot drop walker on the tibialis anterior muscle. The improvement of ankle dorsi exion function and the movement of the active at track can help promote the exion of the knee joint, so the knee exion angle increases after treatment (p < 0.001). The improvement of the ankle dorsi exion function and the driving of the movable at track help to promote hip exion and knee exion, so the angle of hip exion and knee exion increased after treatment (p < 0.05).
To sum up, the combination of foot drop stimulator and moving treadmill can promote the recovery of lower limb motor function, improve foot sag, ankle exion, knee exion and hip exion ability, thereby improving foot drop gait.  Authors' contributions Chen Peishun carried out the studies, drafted the manuscript. Zhang Wanrong participated in case collection. Li Taotao participated in assessment and patient treatment. Guan Hongli participated in the design of the study and performed the statistical analysis. Min Yu conceived of the study, and participated in its design and coordination and helped to draft the manuscript. Zhou Haiwang helped to draft the manuscript. All authors read and approved the nal manuscript.