The first metatarsophalangeal joint bending plays an important role in the foot movement. However, the existing researches mainly focused on the movement scope of the joint and the clinical treatments of related foot diseases. In order to investigate the effects of the first metatarsophalangeal joint bending on human walking gait stability, the present researchers recruited 6 healthy young men to perform the first metatarsophalangeal joint constraint (FM-JC) and barefoot (BF) walking tests. Data of the temporal and spatial parameters, the joint angles of lower limbs, the ground reaction forces (GRF) and utilized coefficients of friction (UCOF) were collected and analyzed. The results showed that, since hip and knee could produce compensation motions, the FMJC had no significant effects on waking gait, but the slip and fall probability increased significantly.
Aiming at the gait instability phenomenon under disturbed conditions, domestic and foreign scholars have done some research works, but the relationship between the independent balancing act with the surface electromyographic and gait parameters in the process of instability has yet rarely been involved. In this study, using the gait analysis combined with electromyographic signal analysis, we investigated balance adjustment mechanism of joints and muscles of the human lower limb under the condition of walking on the level trail and after foot heel touching the ground and unexpected sliding. Studying 10 healthy subjects with the unified shoes, we acquired and analyzed the changing rule of the lower limb joint torque, joint angle, and the surface electromyographic of the main muscle groups involved in situations of dry or oid trails. Studies showed that when accident sliding happened, the body would increase ankle dorsiflexion torque moment, knee unbend torque and straight angle, and meanwhile increase the torque of hip extension, and timely adjust muscle activation time (Followed by activation of Tibialis anterior muscle→Rectus femoris→Gastrocnemius→Femoral biceps) to adjust the center of gravity, to maintain balance of the body, and to avoid falling down. The results of the research could be used to explore new ideas and to provide a certain reference value for preventing slip damage, rehabilitation training and development of lower limb walker.
Nowadays, for gait instability phenomenon, many researches have been carried out at home and abroad. However, the relationship between plantar pressure and gait parameters in the process of balance adjustment is still unclear. This study describes the human body adaptive balance reaction during slip events on slippery level walk by plantar pressure and gait analysis. Ten healthy male subjects walked on a level path wearing shoes with two contrastive contaminants (dry, oil). The study collected and analyzed the change rule of spatiotemporal parameters, plantar pressure parameters, vertical ground reaction force (VGRF), etc. The results showed that the human body adaptive balance reaction during slip events on slippery level walk mainly included lighter touch at the heel strikes, tighter grip at the toe offs, a lower velocity, a shorter stride length and longer support time. These changes are used to maintain or recover body balance. These results would be able to explore new ideas and provide reference value for slip injury prevention, walking rehabilitation training design, research and development of walking assistive equipments, etc.
Utilized coefficient of friction (UCOF), which is calculated with ground reaction forces (GRF), is an effective factor to predict the possibility of slip. For researching the UCOF values of different turning strategies and then predicting the possibility of slip, this study selected 10 healthy young men to perform straight walking and 60° and 90° turning using two turning strategies (step turning and spin turning). ATMI force plate was used to collect the data of GRF, and then the UCOF values of different walking conditions were calculated. The study showed that difference of the medial-lateral force in different walking conditions was great; the slip possibility of turning was significantly greater than that of straight walking. For spin turn, turning angle had no significant effect on peak UCOF values. For step turn, the propulsive force decreased with the increase of turning angle, which caused a result that the peak UCOF values of 60° turn were significantly greater than that for 90° turn. This suggests that turning angle had little effect on possibility of slip of spin turning but great effect on that of step turning, and the greater angle led smaller possibility of slip.
In this paper, the research has been conducted by the Microsoft kinect for windows v2 for obtaining the walking trajectory data from hemiplegic patients, based on which we achieved automatic identification of the hemiplegic gait and sorted the significance of identified features. First of all, the experimental group and two control groups were set up in the study. The three groups of subjects respectively completed the prescribed standard movements according to the requirements. The walking track data of the subjects were obtained straightaway by Kinect, from which the gait identification features were extracted: the moving range of pace, stride and center of mass (up and down/left and right). Then, the bayesian classification algorithm was utilized to classify the sample set of these features so as to automatically recognize the hemiplegia gait. Finally, the random forest algorithm was used to identify the significance of each feature, providing references for the diagnose of disease by ranking the importance of each feature. This thesis states that the accuracy of classification approach based on bayesian algorithm reaches 96%; the sequence of significance based on the random forest algorithm is step speed, stride, left-right moving distance of the center of mass, and up-down moving distance of the center of mass. The combination of step speed and stride, and the combination of step speed and center of mass moving distance are important reference for analyzing and diagnosing of the hemiplegia gait. The results may provide creative mind and new references for the intelligent diagnosis of hemiplegia gait.
ObjectiveTo explore the rehabilitation effect of a domestic lower limb rehabilitation robot on patients with chronic stroke.MethodsChronic stroke patients who were hospitalized in the Department of Rehabilitation Medicine, the First Affiliated Hospital of Chongqing Medical University from September 2017 to August 2019 were collected. These patients underwent A3 robot-assisted gait training for 6 weeks. The differences of gait parameters, spatiotemporal asymmetries, total score and score of each item of Barthel Index were analyzed before and after 6 weeks training.ResultsA total of 15 patients were included, and 12 patients finally completed the trial. After the training, the gait parameters of patients with chronic stroke were significantly improved. Comparing with the baseline data, the cadence, stride length, velocity, step length of the affected leg, and step length of the healthy leg significantly increased (P<0.05) after the training; the stride time and the double-support time were significantly shorter (P<0.05); the stance phase of the affected leg was shortened (P<0.05); the swing phase of the affected leg was prolonged (P<0.05); While no significant difference in the stance phase or swing phase of the healthy leg was found (P>0.05). The spatiotemporal asymmetries had no significant change compared with the baseline data, including the ratio of step length [(1.26±0.23) vs. (1.13±0.10); t=1.816, P=0.097] and the ratio of swing phase of both lower limbs [1.14 (0.23) vs. 1.10 (0.38); Z=?0.153, P=0.878]. The activities of daily living were improved after the training, and the total score of Barthel Index [(72.92± 13.05) vs. (85.42±14.38); t=?6.966, P<0.001] was significantly higher than that before the training. Among the items, the scores of bathing [0.00 (3.75) vs. 5.00 (5.00); Z=?2.000, P=0.046], walking on the flat ground [10.00 (3.75) vs. 15.00 (5.00); Z=?3.000, P=0.003], and going up and down stairs [5.00 (5.00) vs. 7.50 (5.00), Z=?3.000, P=0.003] were higher than the baseline data, and the differences were statistically significant.ConclusionsA3 robot-assisted gait training can effectively improve the walking ability and activities of daily living of patients with chronic stroke but not the spatiotemporal asymmetries. Whether the spatiotemporal asymmetries can be improved by adjusting the robot equipment parameters needs to be further studied.
This study aims to establish a multi-segment foot model which can be applied in dynamic gait simulation. The effectiveness and practicability of this model were verified afterwards by comparing simulation results with those of previous researches. Based on a novel hybrid dynamic gait simulator, bone models were imported into automatic dynamic analysis of mechanical systems (ADAMS). Then, they were combined with ligaments, fascia, muscle and plantar soft tissue that were developed in ADMAS. Multi-segment foot model was consisted of these parts. Experimental data of human gait along with muscle forces and tendon forces from literature were used to drive the model and perform gait simulation. Ground reaction forces and joints revolution angles obtained after simulation were compared with those of previous researches to validate this model. It showed that the model developed in this paper could be used in the dynamic gait simulation and would be able to be applied in the further research.
This paper presents a wearable exoskeleton robot system to realize walking assist function, which oriented toward the patients or the elderly with the mild impairment of leg movement function, due to illness or natural aging. It reduces the loads of hip, knee, ankle and leg muscles during walking by way of weight support. In consideration of the characteristics of the psychological demands and the disease, unlike the weight loss system in the fixed or followed rehabilitation robot, the structure of the proposed exoskeleton robot is artistic, lightweight and portable. The exoskeleton system analyzes the user's gait real-timely by the plantar pressure sensors to divide gait phases, and present different control strategies for each gait phase. The pressure sensors in the seat of the exoskeleton system provide real-time monitoring of the support efforts. And the drive control uses proportion-integral-derivative (PID) control technology for torque control. The total weight of the robot system is about 12.5 kg. The average of the auxiliary support is about 10 kg during standing, and it is about 3 kg during walking. The system showed, in the experiments, a certain effect of weight support, and reduction of the pressure on the lower limbs to walk and stand.
ObjectiveTo explore the gait trajectory characteristics and effectiveness after unicompartmental knee arthroplasty (UKA).MethodsThirty patients (30 knees) with anterior medial compartment osteoarthritis who were treated with UKA between January 2017 and December 2018 were selected as subjects (UKA group). According to age, gender, and side, 30 patients (30 knees) with knee osteoarthritis treated with total knee arthroplasty (TKA) were selected as control (TKA group). In addition to the range of motion (ROM) before operation showing significant difference between the two groups (t=4.25, P=0.00), there was no significant difference in gender, age, disease duration, sides, body mass index, and preoperative hip-knee-ankle angle (HKA), Western Ontario and McMaster University Osteoarthritis Index (WOMAC) score between the two groups (P>0.05). The incision length, drainage volume within 24 hours after operation, and the changes of hemoglobin and albumin were recorded. The WOMAC score, ROM, and HKA before and after operation were compared between the two groups. At 1 year after operation, the gait trajectory characteristics of two groups were analyzed by Vicon three-dimensional gait capture system, and the absolute symmetry index (ASI) of the lower limbs of the two groups was calculated.ResultsThe incisions of the two groups healed by first intention, with no complications. The incision length, drainage volume within 24 hours, and the changes of hemoglobin and albumin after operation in the UKA group were significantly smaller than those in the control group (P<0.05). All patients were followed up completely, the follow-up time ranged from 13 to 20 months of UKA group (mean, 18 months) and 16 to 24 months of control group (mean, 20 months). The imaging review showed that the lower limb alignment of the two groups were restored to a neutral position, and the position of prosthesis was good. At 1 year after operation, the WOMAC score, HKA, and ROM of two groups were significantly improved when compared with those before operation (P<0.05); the postoperative WOMAC score and ROM of the UKA group were significantly better than those of the control group (P<0.05), and there was no significant difference in HKA between the two groups (t=1.54, P=0.13). Gait analysis at 1 year after operation showed that the walking speed, stride length, knee extension at mid-stance, and flexion at swing in the UKA group were significantly better than those in the TKA group (P<0.05); there was no significant difference in cadence, knee flexion at initial contact, and knee flexion at loading response between the two groups (P>0.05). The ASI of bilateral knee flexion in the UKA group was significantly greater than that in the TKA group during the initial contact and loading response period (P<0.05).ConclusionCompared with TKA, UKA has the advantages of small incision, less blood loss, and quicker functional recovery. The early gait after UKA is mainly manifested as the increase in walking speed, stride length, knee flexion at swing, and extension at mid-stance phase. From the analysis of gait symmetry, during the initial contact and loading response phase, the operation side after UKA undertakes more shock absorption and joint stabilization functions than the contralateral side.
Turning gait is very common in daily lives. However, study of turning is still limited. For researching the differences of the walking characteristics between straight gait and turning gait and between different turning strategies, and for analyzing the endopathic factor, this study selected 10 healthy young men to perform straight walking and 90° turning using two turning strategies (outside leg turning and inside leg turning). The Vicon capture system and plantar pressure capture system were used to measure gait parameters and plantar pressure parameters at the same time. The study showed that stride velocity reduced while stride time and proportion of stance time increased when turning was compared to straight walking. Inside leg turning strategy needed stronger muscle controlling and could promote turning, while outside leg turning strategy was more stable. This results will offer data for projecting gait of biped robot and provide reference value for walking rehabilitation training design and development of walking assistive equipments, etc.