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.
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.
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.
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.
Based on force sensing resistor(FSR) sensor, we designed insoles for pressure measurement, which were stable and reliable with a simple structure, and easy to wear and to do outdoor experiments with. So the insoles could be used for gait detection system. The hardware includes plantar pressure sensor array, signal conditioning unit and main circuit unit. The software has the function of data acquisition, signal processing, feature extraction and classification function. We collected 27 groups of gait data of a healthy person based on this system to analyze the data and study pressure distribution under various gait features, i.e. walking on the flat ground, uphill, downhill, up the stairs, and down the stairs. These five gait patterns for pattern recognition and classification by K-nearest neighbors (KNN) recognition algorithm reached up to 90% accuracy. This preliminarily verified the usefulness of the system.
The purpose of this study is to determine how restricting inversion-eversion and pronation-supination motions of the ankle joint complex influences the stability of human gait. The experiment was carried out on a slippery level ground walkway. Spatiotemporal gait parameter, kinematics and kinetics data as well as utilized coefficient of friction (UCOF) were compared between two conditions, i.e. with restriction of the ankle joint complex inversion-eversion and pronation-supination motions (FIXED) and without restriction (FREE). The results showed that FIXED could lead to a significant increase in velocity and stride length and an obvious decrease in double support time. Furthermore, FIXED might affect the motion angle range of knee joint and ankle joint in the sagittal plane. In FIXED condition, UCOF was significantly increased, which could lead to an increase of slip probability and a decrease of gait stability. Hence, in the design of a walker, bipedal robot or prosthetic, the structure design which is used to achieve the ankle joint complex inversion-eversion and pronation-supination motions should be implemented.
Objective To explore the effects of fibulectomy on lower limb function and gait of adult patients through gait analysis, in order to provide guidance for clinical treatment. Methods A clinical data of 24 patients who underwent fibulectomy and met the selection criteria between January 2017 and December 2022 was retrospectively analyzed. There were 12 males and 12 females with an average age of 25 years (range, 18-68 years). The length of fibulectomy was 10-19 cm, with an average of 15 cm. The patients underwent routine rehabilitation training after operation. The occurrence of postoperative complications was recorded, the pain degree of surgical incision was evaluated by visual analogue scale (VAS) score, and the residual fibular bone was reviewed by imaging. A gait test system was used before operation and at 6 months after operation to collect gait data of healthy and affected sides under slow, medium, and fast velocity conditions, including gait parameters (foot rotation angle, step length, support phase, swing phase, gait line length, single support line, maximum force 1, maximum force 2) and the tripod area parameters (maximum pressure, time maximum force, and contact time of forefoot, midfoot, and hindfoot). Results All incisions healed by first intention after operation. All patients were followed up 1-5 years, with an average of 3 years. The great dorso-extension muscle strength decreased in 3 cases, and the sensory defects in the operative area and distal part occurred in 5 cases. The VAS scores of incisions were 0-6 (mean, 4) at 6 months after operation and 0-5 (mean, 2) at last follow-up. During follow-up, imaging review showed that 5 cases had osteoporotic changes of distal residual bone of the fibula, and the residual segment was shorter and more significant; 3 cases had new bone formation. The results of gait test showed that the gait parameters and the tripod area parameters under the three gait speeds were consistent. There was no significant difference in the gait parameters and the tripod area parameters between the healthy side and the affected side before operation (P>0.05). Compared with the healthy side, the foot rotation angle, the single support line, the maximum force 1, the maximum force 2, and the maximum pressures of the forefoot and midfoot of the affected side significantly decreased after operation (P<0.05), and the step length, the time maximum force of midfoot and hindfoot, and the contact time of the forefoot and midfoot significantly increased (P<0.05). Compared with preoperative conditions on the same side, the foot rotation angle, the gait line length of both sides significantly decreased (P<0.05), and the maximum pressures of the forefoot, midfoot, and hindfoot and the time maximum force of the midfoot significantly increased (P<0.05); the step length on healthy side significantly decreased, while the affected side significantly increased (P<0.05); the maximum force 1 and the maximum force 2 on the healthy side significantly increased, while the affected side significantly decreased (P<0.05); the single support line on the affected side significantly decreased (P<0.05). Conclusion Different degrees of clinical symptoms occurred, gait pattern changes, compensatory gait appears, gait stability decreases, and the risk of tumble increases in adult patients after partial fibulectomy. Therefore, it is recommended to walk slowly after fibulectomy.
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.
Objective To investigate the changes of knee joint kinematics after anterior cruciate ligament (ACL) reconstruction assisted by personalized femoral positioner based on the apex of deep cartilage (ADC). Methods Between January 2021 and January 2022, a total of 40 patients with initial ACL rupture who met the selection criteria were randomly divided into the study group (using the personalized femoral positioner based on ADC design to assist ACL reconstruction) and the control group (not using the personalized femoral positioner to assist ACL reconstruction), with 20 patients in each group. Another 20 volunteers with normal knee were collected as a healthy group. There was no significant difference in gender, age, body mass index, and affected side between groups (P>0.05). Gait analysis was performed at 3, 6, and 12 months after operation using Opti _ Knee three-dimensional knee joint motion measurement and analysis system, and the 6 degrees of freedom (flexion and extension angle, varus and valgus angle, internal and external rotation angle, anteroposterior displacement, superior and inferior displacement, internal and external displacement) and motion cycle (maximum step length, minimum step length, and step frequency) of the knee joint were recorded. The patients’ data was compared to the data of healthy group. Results In the healthy group, the flexion and extension angle was (57.80±3.45)°, the varus and valgus angle was (10.54±1.05)°, the internal and external rotation angle was (13.02±1.66)°, and the anteroposterior displacement was (1.44±0.39) cm, the superior and inferior displacement was (0.86±0.20) cm, and the internal and external displacement was (1.38±0.39) cm. The maximum step length was (51.24±1.29) cm, the minimum step length was (45.69±2.28) cm, and the step frequency was (12.45±0.47) step/minute. Compared with the healthy group, the flexion and extension angles and internal and external rotation angles of the patients in the study group and the control group decreased at 3 months after operation, and the flexion and extension angles of the patients in the control group decreased at 6 months after operation, and the differences were significant (P<0.05); there was no significant difference in the other time points and other indicators when compared with healthy group (P>0.05). In the study group, the flexion and extension angles and internal and external rotation angles at 6 and 12 months after operation were significantly greater than those at 3 months after operation (P<0.05), while there was no significant difference in the other indicators at other time points (P>0.05). There was a significant difference in flexion and extension angle between the study group and the control group at 6 months after operation (P<0.05), but there was no significant difference of the indicators between the two groups at other time points (P>0.05).Conclusion Compared with conventional surgery, ACL reconstruction assisted by personalized femoral positioner based on ADC design can help patients achieve more satisfactory early postoperative kinematic results, and three-dimensional kinematic analysis can more objectively and dynamically evaluate the postoperative recovery of knee joint.