Assessment of locomotion recovery in preclinical studies of experimental spinal cord injury remains challenging. We studied the CatWalk XT■gait analysis for evaluating hindlimb functional recovery in a widely used an...Assessment of locomotion recovery in preclinical studies of experimental spinal cord injury remains challenging. We studied the CatWalk XT■gait analysis for evaluating hindlimb functional recovery in a widely used and clinically relevant thoracic contusion/compression spinal cord injury model in rats. Rats were randomly assigned to either a T9 spinal cord injury or sham laminectomy. Locomotion recovery was assessed using the Basso, Beattie, and Bresnahan open field rating scale and the CatWalk XT■gait analysis. To determine the potential bias from weight changes, corrected hindlimb(H) values(divided by the unaffected forelimb(F) values) were calculated. Six weeks after injury, cyst formation, astrogliosis, and the deposition of chondroitin sulfate glycosaminoglycans were assessed by immunohistochemistry staining. Compared with the baseline, a significant spontaneous recovery could be observed in the CatWalk XT■parameters max intensity, mean intensity, max intensity at%, and max contact mean intensity from 4 weeks after injury onwards. Of note, corrected values(H/F) of CatWalk XT■parameters showed a significantly less vulnerability to the weight changes than absolute values, specifically in static parameters. The corrected CatWalk XT■parameters were positively correlated with the Basso, Beattie, and Bresnahan rating scale scores, cyst formation, the immunointensity of astrogliosis and chondroitin sulfate glycosaminoglycan deposition. The CatWalk XT■gait analysis and especially its static parameters, therefore, seem to be highly useful in assessing spontaneous recovery of hindlimb function after severe thoracic spinal cord injury. Because many CatWalk XT■parameters of the hindlimbs seem to be affected by body weight changes, using their corrected values might be a valuable option to improve this dependency.展开更多
Medical research on neurologic ailments requires representative animal models to validate treatments before they are translated to human clinical trials.Rodents are the predominant animal model used in neurological re...Medical research on neurologic ailments requires representative animal models to validate treatments before they are translated to human clinical trials.Rodents are the predominant animal model used in neurological research despite limited anatomic and physiologic similarities to humans.As a result,functional testing designed to assess locomotor recovery after neurologic impairment is well established in rodent models.Comparatively,large r,more clinically relevant models have not been as well studied.To achieve similar locomotor testing standardization in larger animals,the models must be accessible to a wide array of researchers.Non-human primates are the most relevant animal model fo r translational research,however ethical and financial barriers limit their accessibility.This review focuses on swine,sheep,and goats as large animal alternatives for transitional studies between rodents and non-human primates.The objective of this review is to compare motor testing and data collection methods used in swine,sheep,and goats to encourage testing standardization in these larger animal models.The PubMed database was analyzed by searching combinations of swine,sheep,and goats,neurologic injuries,and functional assessments.Findings were categorized by animal model,data collection method,and assessment design.Swine and sheep were used in the majority of the studies,while only two studies were found using goats.The functional assessments included open pen analysis,treadmill walking,and guided free walking.Data collection methods included subjective behavioral rating scales and objective tools such as pressure-sensitive mats and image-based analysis software.Overall,swine and sheep were well-suited for a variety of assessment designs,with treadmill walking and guided free walking offering the most consistency across multiple trials.Data collection methods varied,but image-based gait analysis software provided the most robust analysis.Future studies should be conducted to standardize functional testing methods after neurologic impairment in large animals.展开更多
Human Activity Recognition(HAR)has always been a difficult task to tackle.It is mainly used in security surveillance,human-computer interaction,and health care as an assistive or diagnostic technology in combination w...Human Activity Recognition(HAR)has always been a difficult task to tackle.It is mainly used in security surveillance,human-computer interaction,and health care as an assistive or diagnostic technology in combination with other technologies such as the Internet of Things(IoT).Human Activity Recognition data can be recorded with the help of sensors,images,or smartphones.Recognizing daily routine-based human activities such as walking,standing,sitting,etc.,could be a difficult statistical task to classify into categories and hence 2-dimensional Convolutional Neural Network(2D CNN)MODEL,Long Short Term Memory(LSTM)Model,Bidirectional long short-term memory(Bi-LSTM)are used for the classification.It has been demonstrated that recognizing the daily routine-based on human activities can be extremely accurate,with almost all activities accurately getting recognized over 90%of the time.Furthermore,because all the examples are generated from only 20 s of data,these actions can be recognised fast.Apart from classification,the work extended to verify and investigate the need for wearable sensing devices in individually walking patients with Cerebral Palsy(CP)for the evaluation of chosen Spatio-temporal features based on 3D foot trajectory.Case-control research was conducted with 35 persons with CP ranging in weight from 25 to 65 kg.Optical Motion Capture(OMC)equipment was used as the referral method to assess the functionality and quality of the foot-worn device.The average accuracy±precision for stride length,cadence,and step length was 3.5±4.3,4.1±3.8,and 0.6±2.7 cm respectively.For cadence,stride length,swing,and step length,people with CP had considerably high inter-stride variables.Foot-worn sensing devices made it easier to examine Gait Spatio-temporal data even without a laboratory set up with high accuracy and precision about gait abnormalities in people who have CP during linear walking.展开更多
Parkinson’s disease is identified as one of the key neurodegenerative disorders occurring due to the damages present in the central nervous system.The cause of such brain damage seems to be fully explained in many res...Parkinson’s disease is identified as one of the key neurodegenerative disorders occurring due to the damages present in the central nervous system.The cause of such brain damage seems to be fully explained in many research studies,but the understanding of its functionality remains to be impractical.Specifically,the development of a quantitative disease prediction model has evolved in recent decades.Moreover,accelerometer sensor-based gait analysis is accepted as an important tool for recognizing the walking behavior of the patients during the early prediction and diagnosis of Parkinson’s disease.This type of minimal infrastructure equipment helps in analyzing the Parkinson’s gait properties without affecting the common behavioral patterns during the clinical practices.Therefore,the Accelerometer Sensor-based Parkinson’s Disease Identi-fication System(ASPDIS)is introduced with a kernel-based support vector machine classifier model to make an early prediction of the disease.consequently,the proposed classifier can easily predict various severity levels of Parkinson’s disease from the sensor data.The performance of the proposed classifier is com-pared against the existing models such as random forest,decision tree,and k-near-est neighbor classifiers respectively.As per the experimental observation,the proposed classifier has more capability to differentiate Parkinson’s from non-Parkinson patients depending upon the severity levels.Also,it is found that the model has outperformed the existing classifiers concerning prediction time and accuracy respectively.展开更多
Introduction: Gait analysis of an adult man after trans-metatarsal unilateral amputation is described. Objective: Instrumental gait analysis of a subject 15 years after trans-metatarsal unilateral amputation in two fo...Introduction: Gait analysis of an adult man after trans-metatarsal unilateral amputation is described. Objective: Instrumental gait analysis of a subject 15 years after trans-metatarsal unilateral amputation in two footwear conditions: while walking barefoot and with prosthesis. Materials and Methods: In a movement analysis laboratory, locomotion studies were carried out at freely chosen walking speed by a 65-year-old subject, obtaining kinematic, kinetic and surface electromyographic data in time and space. Gait analysis was performed using instrumental technologies from a digital eco-system applying walking protocols. Results: When the patient wore the prosthesis, several positive improvements were observed in various aspects of gait. These included enhancements in the base of support, gait speed, and joint range of movements. Additionally, there was a slight improvement in the vertical ground reaction forces pattern, indicating a positive effect of the assistive technology. Furthermore, the use of the prosthesis led to a more organized pattern of muscle activity, which further supports its beneficial impact. However, it is worth noting that some challenges still persisted, particularly regarding stabilizing the body during the double support phase. Despite this difficulty, the overall findings suggest that the use of the prosthesis offers valuable improvements to the patient’s gait dynamics. Conclusions: After conducting a thorough analysis of the parameters related to the gait of a subject who underwent a trans-metatarsal unilateral amputation fifteen years ago, it was found that the use of prosthesis had a positive impact. This study demonstrated important improvements in some kinematic and kinetic parameters, including muscle activation patterns, indicating an increase in comfort and confidence while utilizing the prosthetic device.展开更多
AIM To describe,using gait analysis,the development of spinal motion in the growing child.METHODS Thirty-six healthy children aged from 3 to 16 years old were included in this study for a gait analysis(9m-walk).Variou...AIM To describe,using gait analysis,the development of spinal motion in the growing child.METHODS Thirty-six healthy children aged from 3 to 16 years old were included in this study for a gait analysis(9m-walk).Various kinematic parameters were recorded and analyzed such as thoracic angle(TA),lumbar angle(LA)and sagittal vertical axis(SVA).The kinetic parameters were the net reaction moments(N.m/kg)at the thoracolumbar and lumbosacral junctions.RESULTS TA and LA curves were not statistically correlated to the age(respectively,P=0.32 and P=0.41).SVA increased significantly with age(P<0.001).Moments in sagittal plane at the lumbosacral junction were statistically correlated to the age(P=0.003),underlining the fact that sagittal mechanical constraints at the lumbosacral junction increase with age.Moments in transversal plane at the thoracolumbar and lumbosacral junctions were statistically correlated to the age(P=0.0002and P=0.0006),revealing that transversal mechanical constraints decrease with age.CONCLUSION The kinetic analysis showed that during growth,a decrease of torsional constraint occurs while an increase of sagittal constraint is observed.These changes in spine biomechanics are related to the crucial role of the trunk for bipedalism acquisition,allowing stabilization despite lower limbs immaturity.With the acquisition of mature gait,the spine will mainly undergo constraints in the sagittal plane.展开更多
[Objectives]To observe the effect of motor relearning combined with transcranial direct current stimulation on the motor function of lower extremities in patients with cerebral infarction,and to observe its effect on ...[Objectives]To observe the effect of motor relearning combined with transcranial direct current stimulation on the motor function of lower extremities in patients with cerebral infarction,and to observe its effect on gait by 3D gait analysis.[Methods]60 patients with cerebral infarction who met the inclusion criteria were randomly divided into 3 groups according to the order of treatment(n=20).Group A received motor relearning treatment,group B received transcranial direct current stimulation treatment,group C received motor relearning combined with transcranial direct current stimulation,and the curative effect was observed after 5 courses of treatment.[Results]Before treatment,FMA,MBI,spatio-temporal parameters for 3D gait analysis(gait frequency,gait cycle,stride length,gait speed,stride length deviation,double support)and lower limb joint motion parameters(affected side stride length,maximum hip flexion,maximum hip extension,maximum knee flexion,maximum knee extension,stance phase,swing phase)were compared among the three groups.After treatment,the FMA and MBI of the three groups increased,and the spatio-temporal parameters for 3D gait analysis(gait frequency,gait cycle,gait speed,double support)and the lower limb joint motion parameters(affected side stride length,maximum hip flexion,maximum hip extension,maximum knee flexion,swing phase)were all improved,while the spatio-temporal parameters(stride length and stride length deviation)and the lower limb joint motion parameters(maximum knee extension and stance phase)decreased.Compared with those before treatment,there were significant differences among the three groups(P<0.05).Through the comparison between groups,it was found that the FMA,MBI,spatio-temporal parameters for 3D gait analysis(gait frequency,gait cycle,gait speed,double support)and lower limb joint motion parameters(affected side stride length,maximum hip flexion,maximum hip extension,maximum knee flexion,swing phase)in group C were significantly higher than those in group A and B,while the spatio-temporal parameters(stride length and stride length deviation)and lower limb joint motion parameters(maximum knee extension and stance phase)in group C were significantly lower than those in group A and group B,and the difference was statistically significant(P<0.05).[Conclusions]Motor relearning combined with transcranial direct current stimulation could increase MBI and FMA,improve gait spatio-temporal parameters and lower limb joint motion parameters,and correct abnormal gait in patients with cerebral infarction.展开更多
The equivalent mechanism of the system is often considered as one specific mechanism in most existing studies of multi-legged robots, however the equivalent mechanism is varying while the robot moves on the ground. Fo...The equivalent mechanism of the system is often considered as one specific mechanism in most existing studies of multi-legged robots, however the equivalent mechanism is varying while the robot moves on the ground. Four typical tripod period gaits of a radial symmetrical six-legged robot are analyzed. Similar to the metamorphic mechanism, the locomotion of multi-legged robot is considered as a series of varying hybrid serial-parallel mechanisms by assuming the constraints of the feet on the ground with hinges. One gait cycle is divided into several periods, and in different walking period there is a specific equivalent mechanism corresponding to it, and the walking process of multi-legged robot is composed by these series of equivalent mechanisms. Walking performance can be got by analyzing these series of equivalent mechanisms. Kinematics model of the equivalent mechanism is established, workspaces of equivalent mechanisms are illustrated by simulation and a concept of static stability workspace is proposed to evaluate the static stability of these four gaits. A new method to calculate the stride length of multi-legged robots is presented by analyzing the relationship between the workspace of two adjacent equivalent parallel mechanisms in one gait cycle. The stride lengths of four gaits are given by simulations. Comparison of stride length and static stability among these four typical tripod gaits are given. It has been proved that mixed gait and insect-wave gait II have better static stability than mammal kick-off gait and insect-wave gait I. Insect-wave gait II displays its advantage on stride length while the height of robot body lower than 87 mm, mammal kick-off gait has superiority on stride length while the height of robot body higher than 115 mm, and insect-wave gait I shows its shortcoming in stride length. The proposed method based on metamorphic theory and combining the footholds and body height of robot provides a new method to comprehensive analyze the performance of multi-legged robot.展开更多
The previous research regarding the gait planning of quadruped robot focuses on the sequence for lifting o and placing the feet, but neglects the influence of body height. However, body height a ects gait performance ...The previous research regarding the gait planning of quadruped robot focuses on the sequence for lifting o and placing the feet, but neglects the influence of body height. However, body height a ects gait performance significantly, such as in terms of the stride length and stability margin. We herein study the performance of a quadruped robot using the equivalent mechanism concept based on metamorphosis. Assuming the constraints between standing feet and the ground with hinges, the ground, standing legs and robot body are considered as a parallel mechanism, and each swing leg is regarded as a typical serial manipulator. The equivalent mechanism varies while the robot moves on the ground. One gait cycle is divided into several periods, including step forward stages and switching stages. There exists a specific equivalent mechanism corresponding to each gait period. The robot's locomotion can be regarded as the motion of these series of equivalent mechanisms. The kinematics model and simplified model of the equivalent mechanism is established. A new definition of the multilegged robot stability margin, based on friction coe cient, is presented to evaluate the robot stability. The stable workspaces of the equivalent mechanism in the step forward stage of trotting gait under di erent friction coe cients are analyzed. The stride length of the robots is presented by analyzing the relationship between the stable workspaces of the equivalent mechanisms of two adjacent step forward stages in one gait cycle. The simulation results show that the stride length is larger with increasing friction coe cient. We herein propose a new method based on metamorphosis, and an equivalent mechanism to analyze the stability margin and stable workspace of the multilegged robot.展开更多
In this work, a total of 322 tests were taken on young volunteers by performing 10 different falls, 6 different Activities of Daily Living (ADL) and 7 Dynamic Gait Index (DGI) tests using a custom-designed Wireless Ga...In this work, a total of 322 tests were taken on young volunteers by performing 10 different falls, 6 different Activities of Daily Living (ADL) and 7 Dynamic Gait Index (DGI) tests using a custom-designed Wireless Gait Analysis Sensor (WGAS). In order to perform automatic fall detection, we used Back Propagation Artificial Neural Network (BP-ANN) and Support Vector Machine (SVM) based on the 6 features extracted from the raw data. The WGAS, which includes a tri-axial accelerometer, 2 gyroscopes, and a MSP430 microcontroller, is worn by the subjects at either T4 (at back) or as a belt-clip in front of the waist during the various tests. The raw data is wirelessly transmitted from the WGAS to a near-by PC for real-time fall classification. The BP ANN is optimized by varying the training, testing and validation data sets and training the network with different learning schemes. SVM is optimized by using three different kernels and selecting the kernel for best classification rate. The overall accuracy of BP ANN is obtained as 98.20% with LM and RPROP training from the T4 data, while from the data taken at the belt, we achieved 98.70% with LM and SCG learning. The overall accuracy using SVM was 98.80% and 98.71% with RBF kernel from the T4 and belt position data, respectively.展开更多
An experiment was carried out in the key laboratory for Technique Diagnosis and Function Assessment of Winter Sports of China to investigate the differences in gait characteristics between healthy children and childre...An experiment was carried out in the key laboratory for Technique Diagnosis and Function Assessment of Winter Sports of China to investigate the differences in gait characteristics between healthy children and children with spastic hemiplegic cerebral palsy.With permission of their parents,200 healthy children aged 3 to 6 years in the kindergarten of Northeastern University were enrolled in this experiment.Twenty children aged 3 to 6 years with spastic hemiplegic cerebral palsy from Shengjing Hospital,China were also enrolled in this experiment.Standard data were collected by simultaneously recording gait information from two digital cameras.DVracker was used to analyze the standard data.The children with hemiplegic cerebral palsy had a longer gait cycle,slower walking speed,and longer support phase than did the healthy children.The support phase was longer than the swing phase in the children with hemiplegic cerebral palsy.There were significant differences in the angles of the hip,knee,and ankle joint between children with cerebral palsy and healthy children at the moment of touching the ground and buffering,and during pedal extension.Children with hemiplegic cerebral palsy had poor motor coordination during walking,which basically resulted in a short stride,high stride frequency to maintain speed,more obvious swing,and poor stability.展开更多
In this paper, a comparative analysis of walking patterns during different cognitive states is conducted, followed by the classification of our database into Fallers and Non-fallers;by Fallers we describe subjects wit...In this paper, a comparative analysis of walking patterns during different cognitive states is conducted, followed by the classification of our database into Fallers and Non-fallers;by Fallers we describe subjects with repeated falling history. Vertical Ground Reaction Forces (VGRF) acquired from underneath the heel and toes of both feet are processed and analyzed for that endeavor. The subjects underwent three levels of tasks: 1) Single task: Walking at self-selected-speed (MS), 2) Dual task: Walking while performing a verbal fluency task (MF) and 3) Complex Dual task: Walking while counting backwards (MD).The ultimate objective of our research is fall prediction among the elderly by characterizing the variation of time-domain feature of Gait signals. For that, walking VGRF is analyzed and tested for the existence of indicators of the effect of dual task on subject falling susceptibility, whether parametric or pattern-wise analysis. As a result to our work, dual task in Fallers VGRF signals were recognized at 74% while at those non-fallers were recognized at 85%. Most importantly, subjects with history of fall have shown more potential to change the way they walk while performing mathematical cognitive task.展开更多
<div style="text-align:justify;"> With the development of medicine and the improvement of people’s living standards, the issue of rehabilitation is getting more and more attention. Gait rehabilitation...<div style="text-align:justify;"> With the development of medicine and the improvement of people’s living standards, the issue of rehabilitation is getting more and more attention. Gait rehabilitation provides a brand-new treatment method for patients with walking disfunction. It is currently recognized as an advanced rehabilitation medical method in the world. In recent years, the number of patients suffering from dyskinesias in the lower limbs in China has been increasing, and the society's demand for walking rehabilitation treatment is also increasing. The emergence of gait rehabilitation solves the problem of fewer therapists and more patients, reduces the intensity of the therapist’s work, and has the incomparable advantage that traditional rehabilitation methods lack. However, because there are no mature related products in China at present, and the prices of foreign products are very expensive, domestic medical institutions have not yet put them into practice. Accelerating the development of gait re-habilitation equipment is of great significance for improving China’s medical level, improving the quality of life of patients, and reducing social burden. Usually, high-precision optical sensors are installed on human limbs or using high-speed cameras to capture motion. However, due to the high cost of the equipment, the relative high price of image processing software when processing the collected motion data. In this paper, the acceleration sensors are installed on the human body and the data in a gait cycle can be obtained. After smoothing, using it as the input signal for gait feature extraction and classification. In order to classify normal gait and abnormal gait for evaluation and better walking rehabilitation. </div>展开更多
In clinical assessment or sports exercise,it is common that a subject is required to repeat a specific per- formance so that a stable movement pattern is obtained and analysed.In practice,however,the trials done by a ...In clinical assessment or sports exercise,it is common that a subject is required to repeat a specific per- formance so that a stable movement pattern is obtained and analysed.In practice,however,the trials done by a sub- ject vary more or less,depending on the psychological or physical conditions.Some of the trials can be used as rep- resentatives of the stable movement pattern,and some not.Therefore,there is a demand for a new method to identify which trials/curves are similar.The traditional methods used to assess curve similarity are not perfectly suitable for the case where there are only a few of trials available.This study proposes a similarity-distance coefficient to assess the similarity of curves/trials.A group of designed curves are used to validate the coefficient.The results show that given joint kinematic data during gait as examples,the proposed coefficient can be used to quantitatively evaluate the similarity of trials,and thus find which trials would be representative (s) for the gait investigated.The proposed method could be applied in various situations where repeat movements have to be measured and analysed.展开更多
Introduction: gait analysis of a subject with total hip replacement is described. Objective: instrumental gait analysis of a subject 12 years after the total hip arthroplasty. Materials and Methods: in a movement anal...Introduction: gait analysis of a subject with total hip replacement is described. Objective: instrumental gait analysis of a subject 12 years after the total hip arthroplasty. Materials and Methods: in a movement analysis laboratory, locomotion studies were carried out at freely chosen walking speed by a 64-year-old subject, obtaining kinematic, kinetic and surface electromyographic data in time and space. All measurements were assessments by applying walking protocols on a straight surface of 8 m long. Results: abnormal slight activations of semitendinosus and tibialis anterior muscles, of the left limb, were observed throughout the gait cycle, no spatiotemporal parameters far from normal values were detected. Conclusions: it was possible to obtain an exhaustive analysis of the parameters associated with the gait of a subject after 12 years of total hip arthroplasty.展开更多
Purpose:Robot-assisted technology is a forefront of surgical innovation that improves the accuracy of total knee arthroplasty (TKA).But whether the accuracy of surgery can improve the clinical efficacy still needs fur...Purpose:Robot-assisted technology is a forefront of surgical innovation that improves the accuracy of total knee arthroplasty (TKA).But whether the accuracy of surgery can improve the clinical efficacy still needs further research.The purpose of this study is to perform three-dimensional (3D) analysis in the early postoperative period of patients who received robot-assisted total knee arthroplasty (RATKA),and to study the trend of changes in gait parameters after RATKA and the correlation with the early clinical efficacy.Methods:Patients who received RATKA in the Center of Joint Surgery,the First Hospital Affiliated to Army Military Medical University from October 2020 to January 2021 were included.The imaging parameters,i.e.,hip-knee-ankle angle,lateral distal femoral angle,medial proximal tibial angle,posterior condylar angle were measured 3 months post-TKA.The 3D gait analysis and clinical efficacy by Western Ontario Mac Master University Index (WOMAC) score were performed pre-TKA,3 and 6 months post-TKA.The differences in spatiotemporal parameters of gait,kinetic parameters,and kinematic parameters of the operated limb and the contralateral limb were compared.The correlation between gait parameters and WOMAC scores was analyzed.Paired samplet-test and Wilcoxon rank-sum test were used to analyze the difference between groups,and Spearman correlation coefficient was used to analyze the correlation.Results:There were 31 patients included in this study,and the imaging indexes showed that all of them returned to normal post-TKA.The WOMAC score at 3 months post-TKA was significantly lower than that pre-TKA,and there was no significant difference between at 3 and 6 months.The 3D gait analysis results showed that the double support time of the operated limb reduced at 3 and 6 months (allp < 0.05),the maximum extension and maximum external rotation of the knee joint increased at stance phase,and the maximum flexion angle,the range of motion and the maximum external rotation increased at swing phase.Compared with the preoperative data,there were significant improvements (allp < 0.05).Compared with the contralateral knee joint,the maximum external rotation of the knee joint at swing phase was smaller than that of the contralateral side,and the maximum flexion and extension moment was greater than that of the contralateral knee.The maximum external rotation moment of the joint was greater than that of the contralateral knee joint (p < 0.05).There was a negative correlation between the single support time pre-TKA and the WOMAC score at 3 months (p = 0.017),and the single support time at 3 months was negatively correlated with the WOMAC score at 6 months (p = 0.043).The cadence at 6 months was negatively correlated with the WOMAC score at 6 months (p = 0.031).The maximum knee extension at stance phase at 6 months was negatively correlated with the WOMAC score at 6 month (p = 0.048).The maximum external rotation at stance phase at 6 months was negatively correlated with the WOMAC score at 6 months (p = 0.024).Conclusion:The 3D gait analysis of RATKA patients is more sensitive than WOMAC score in evaluating the clinical efficacy.Trend of changes in gait parameters shows that the knee joint support,flexion and extension function,range of motion,external rotation and varus deformity moment of the patient were significantly improved at 3 months after surgery,and continued to 6 months after surgery.Compared with the contralateral knee,the gait parameters of the operated limb still has significant gaps in functionality,such as the external rotation and flexion and extension.The single support time,cadence,knee extension,and knee external rotation of the operated limb have a greater correlation with the postoperative WOMAC score.Postoperative rehabilitation exercises should be emphasized,which is of great value for improving the early efficacy of RATKA.展开更多
Soft climbing/crawling robots have been attracting increasing attention in the soft robotics community,and many prototypes with basic locomotion have been implemented.Most existing soft robots achieve locomotion by pl...Soft climbing/crawling robots have been attracting increasing attention in the soft robotics community,and many prototypes with basic locomotion have been implemented.Most existing soft robots achieve locomotion by planar bending deformation and lack sufficient mobility.Enhancing the mobility of soft climbing/crawling robots is still an open and challenging issue.To this end,we present a novel pneumatic leech-like soft robot,Leechbot,with both bending and stretching deformation for locomotion.With a morphological structure,the robot consists of a three-chambered actuator in the middle for the main motion,two chamber-net actuators that act as ankles,and two suckers at the ends for anchoring on surfaces.The peristaltic motion for locomotion is implemented by body stretching,and direction changing is achieved by body bending.Due to the novel design and two deformation modes,the robot can make turns and transit between different surfaces;the robot,hence,has excellent mobility.The development of the robot prototype is presented in detail in this paper.To control its motion,tests were carried out to determine the relationship between step length and air pressure as well as the relationship between motion speed and periodic delay time.A kinematic model was established,and the kinematic mobility and surface transitionability were analyzed.Gait planning based on the inflating sequence of the actuating chambers is presented for straight crawling,turn making,and transiting between surfaces and was verified by a series of experiments with the prototype.The results show that a high mobility in soft climbing/crawling robots can be achieved by a novel design and by proper gait planning.展开更多
Quadruped animals in the nature realize high energy efficiency locomotion by automatically changing their gait at different speeds.Inspired by this character,an efficient adaptive diagonal gait locomotion controller i...Quadruped animals in the nature realize high energy efficiency locomotion by automatically changing their gait at different speeds.Inspired by this character,an efficient adaptive diagonal gait locomotion controller is designed for quadruped robot.A unique gait planning method is proposed in this paper.As the speed of robot varies,the gait cycle time and the proportion of stance and swing phase of each leg are adjusted to form a variety of gaits.The optimal joint torque is calculated by the controller combined with Virtual Model Control(VMC)and Whole-Body Control(WBC)to realize the desired motion.The gait and step frequency of the robot can automatically adapt to the change of speed.Several experiments are done with a quadruped robot made by our laboratory to verify that the gait can change automatically from slow-trotting to flying-trot during the period when speed is from 0 to 4 m/s.The ratio of swing phase is from less than 0.5 to more than 0.5 to realize the running motion with four feet off the ground.Experiments have shown that the controller can indeed consume less energy when robot runs at a wide range of speeds comparing to the basic controller.展开更多
文摘Assessment of locomotion recovery in preclinical studies of experimental spinal cord injury remains challenging. We studied the CatWalk XT■gait analysis for evaluating hindlimb functional recovery in a widely used and clinically relevant thoracic contusion/compression spinal cord injury model in rats. Rats were randomly assigned to either a T9 spinal cord injury or sham laminectomy. Locomotion recovery was assessed using the Basso, Beattie, and Bresnahan open field rating scale and the CatWalk XT■gait analysis. To determine the potential bias from weight changes, corrected hindlimb(H) values(divided by the unaffected forelimb(F) values) were calculated. Six weeks after injury, cyst formation, astrogliosis, and the deposition of chondroitin sulfate glycosaminoglycans were assessed by immunohistochemistry staining. Compared with the baseline, a significant spontaneous recovery could be observed in the CatWalk XT■parameters max intensity, mean intensity, max intensity at%, and max contact mean intensity from 4 weeks after injury onwards. Of note, corrected values(H/F) of CatWalk XT■parameters showed a significantly less vulnerability to the weight changes than absolute values, specifically in static parameters. The corrected CatWalk XT■parameters were positively correlated with the Basso, Beattie, and Bresnahan rating scale scores, cyst formation, the immunointensity of astrogliosis and chondroitin sulfate glycosaminoglycan deposition. The CatWalk XT■gait analysis and especially its static parameters, therefore, seem to be highly useful in assessing spontaneous recovery of hindlimb function after severe thoracic spinal cord injury. Because many CatWalk XT■parameters of the hindlimbs seem to be affected by body weight changes, using their corrected values might be a valuable option to improve this dependency.
文摘Medical research on neurologic ailments requires representative animal models to validate treatments before they are translated to human clinical trials.Rodents are the predominant animal model used in neurological research despite limited anatomic and physiologic similarities to humans.As a result,functional testing designed to assess locomotor recovery after neurologic impairment is well established in rodent models.Comparatively,large r,more clinically relevant models have not been as well studied.To achieve similar locomotor testing standardization in larger animals,the models must be accessible to a wide array of researchers.Non-human primates are the most relevant animal model fo r translational research,however ethical and financial barriers limit their accessibility.This review focuses on swine,sheep,and goats as large animal alternatives for transitional studies between rodents and non-human primates.The objective of this review is to compare motor testing and data collection methods used in swine,sheep,and goats to encourage testing standardization in these larger animal models.The PubMed database was analyzed by searching combinations of swine,sheep,and goats,neurologic injuries,and functional assessments.Findings were categorized by animal model,data collection method,and assessment design.Swine and sheep were used in the majority of the studies,while only two studies were found using goats.The functional assessments included open pen analysis,treadmill walking,and guided free walking.Data collection methods included subjective behavioral rating scales and objective tools such as pressure-sensitive mats and image-based analysis software.Overall,swine and sheep were well-suited for a variety of assessment designs,with treadmill walking and guided free walking offering the most consistency across multiple trials.Data collection methods varied,but image-based gait analysis software provided the most robust analysis.Future studies should be conducted to standardize functional testing methods after neurologic impairment in large animals.
文摘Human Activity Recognition(HAR)has always been a difficult task to tackle.It is mainly used in security surveillance,human-computer interaction,and health care as an assistive or diagnostic technology in combination with other technologies such as the Internet of Things(IoT).Human Activity Recognition data can be recorded with the help of sensors,images,or smartphones.Recognizing daily routine-based human activities such as walking,standing,sitting,etc.,could be a difficult statistical task to classify into categories and hence 2-dimensional Convolutional Neural Network(2D CNN)MODEL,Long Short Term Memory(LSTM)Model,Bidirectional long short-term memory(Bi-LSTM)are used for the classification.It has been demonstrated that recognizing the daily routine-based on human activities can be extremely accurate,with almost all activities accurately getting recognized over 90%of the time.Furthermore,because all the examples are generated from only 20 s of data,these actions can be recognised fast.Apart from classification,the work extended to verify and investigate the need for wearable sensing devices in individually walking patients with Cerebral Palsy(CP)for the evaluation of chosen Spatio-temporal features based on 3D foot trajectory.Case-control research was conducted with 35 persons with CP ranging in weight from 25 to 65 kg.Optical Motion Capture(OMC)equipment was used as the referral method to assess the functionality and quality of the foot-worn device.The average accuracy±precision for stride length,cadence,and step length was 3.5±4.3,4.1±3.8,and 0.6±2.7 cm respectively.For cadence,stride length,swing,and step length,people with CP had considerably high inter-stride variables.Foot-worn sensing devices made it easier to examine Gait Spatio-temporal data even without a laboratory set up with high accuracy and precision about gait abnormalities in people who have CP during linear walking.
文摘Parkinson’s disease is identified as one of the key neurodegenerative disorders occurring due to the damages present in the central nervous system.The cause of such brain damage seems to be fully explained in many research studies,but the understanding of its functionality remains to be impractical.Specifically,the development of a quantitative disease prediction model has evolved in recent decades.Moreover,accelerometer sensor-based gait analysis is accepted as an important tool for recognizing the walking behavior of the patients during the early prediction and diagnosis of Parkinson’s disease.This type of minimal infrastructure equipment helps in analyzing the Parkinson’s gait properties without affecting the common behavioral patterns during the clinical practices.Therefore,the Accelerometer Sensor-based Parkinson’s Disease Identi-fication System(ASPDIS)is introduced with a kernel-based support vector machine classifier model to make an early prediction of the disease.consequently,the proposed classifier can easily predict various severity levels of Parkinson’s disease from the sensor data.The performance of the proposed classifier is com-pared against the existing models such as random forest,decision tree,and k-near-est neighbor classifiers respectively.As per the experimental observation,the proposed classifier has more capability to differentiate Parkinson’s from non-Parkinson patients depending upon the severity levels.Also,it is found that the model has outperformed the existing classifiers concerning prediction time and accuracy respectively.
文摘Introduction: Gait analysis of an adult man after trans-metatarsal unilateral amputation is described. Objective: Instrumental gait analysis of a subject 15 years after trans-metatarsal unilateral amputation in two footwear conditions: while walking barefoot and with prosthesis. Materials and Methods: In a movement analysis laboratory, locomotion studies were carried out at freely chosen walking speed by a 65-year-old subject, obtaining kinematic, kinetic and surface electromyographic data in time and space. Gait analysis was performed using instrumental technologies from a digital eco-system applying walking protocols. Results: When the patient wore the prosthesis, several positive improvements were observed in various aspects of gait. These included enhancements in the base of support, gait speed, and joint range of movements. Additionally, there was a slight improvement in the vertical ground reaction forces pattern, indicating a positive effect of the assistive technology. Furthermore, the use of the prosthesis led to a more organized pattern of muscle activity, which further supports its beneficial impact. However, it is worth noting that some challenges still persisted, particularly regarding stabilizing the body during the double support phase. Despite this difficulty, the overall findings suggest that the use of the prosthesis offers valuable improvements to the patient’s gait dynamics. Conclusions: After conducting a thorough analysis of the parameters related to the gait of a subject who underwent a trans-metatarsal unilateral amputation fifteen years ago, it was found that the use of prosthesis had a positive impact. This study demonstrated important improvements in some kinematic and kinetic parameters, including muscle activation patterns, indicating an increase in comfort and confidence while utilizing the prosthetic device.
文摘AIM To describe,using gait analysis,the development of spinal motion in the growing child.METHODS Thirty-six healthy children aged from 3 to 16 years old were included in this study for a gait analysis(9m-walk).Various kinematic parameters were recorded and analyzed such as thoracic angle(TA),lumbar angle(LA)and sagittal vertical axis(SVA).The kinetic parameters were the net reaction moments(N.m/kg)at the thoracolumbar and lumbosacral junctions.RESULTS TA and LA curves were not statistically correlated to the age(respectively,P=0.32 and P=0.41).SVA increased significantly with age(P<0.001).Moments in sagittal plane at the lumbosacral junction were statistically correlated to the age(P=0.003),underlining the fact that sagittal mechanical constraints at the lumbosacral junction increase with age.Moments in transversal plane at the thoracolumbar and lumbosacral junctions were statistically correlated to the age(P=0.0002and P=0.0006),revealing that transversal mechanical constraints decrease with age.CONCLUSION The kinetic analysis showed that during growth,a decrease of torsional constraint occurs while an increase of sagittal constraint is observed.These changes in spine biomechanics are related to the crucial role of the trunk for bipedalism acquisition,allowing stabilization despite lower limbs immaturity.With the acquisition of mature gait,the spine will mainly undergo constraints in the sagittal plane.
基金Supported by Scientific Research Project of Chinese Medicine of Hubei Provincial Health Commission(ZY2021Q015)Project of Taihe Hospital(2021JJXM077,2019JJXM099,2016JJXM023)。
文摘[Objectives]To observe the effect of motor relearning combined with transcranial direct current stimulation on the motor function of lower extremities in patients with cerebral infarction,and to observe its effect on gait by 3D gait analysis.[Methods]60 patients with cerebral infarction who met the inclusion criteria were randomly divided into 3 groups according to the order of treatment(n=20).Group A received motor relearning treatment,group B received transcranial direct current stimulation treatment,group C received motor relearning combined with transcranial direct current stimulation,and the curative effect was observed after 5 courses of treatment.[Results]Before treatment,FMA,MBI,spatio-temporal parameters for 3D gait analysis(gait frequency,gait cycle,stride length,gait speed,stride length deviation,double support)and lower limb joint motion parameters(affected side stride length,maximum hip flexion,maximum hip extension,maximum knee flexion,maximum knee extension,stance phase,swing phase)were compared among the three groups.After treatment,the FMA and MBI of the three groups increased,and the spatio-temporal parameters for 3D gait analysis(gait frequency,gait cycle,gait speed,double support)and the lower limb joint motion parameters(affected side stride length,maximum hip flexion,maximum hip extension,maximum knee flexion,swing phase)were all improved,while the spatio-temporal parameters(stride length and stride length deviation)and the lower limb joint motion parameters(maximum knee extension and stance phase)decreased.Compared with those before treatment,there were significant differences among the three groups(P<0.05).Through the comparison between groups,it was found that the FMA,MBI,spatio-temporal parameters for 3D gait analysis(gait frequency,gait cycle,gait speed,double support)and lower limb joint motion parameters(affected side stride length,maximum hip flexion,maximum hip extension,maximum knee flexion,swing phase)in group C were significantly higher than those in group A and B,while the spatio-temporal parameters(stride length and stride length deviation)and lower limb joint motion parameters(maximum knee extension and stance phase)in group C were significantly lower than those in group A and group B,and the difference was statistically significant(P<0.05).[Conclusions]Motor relearning combined with transcranial direct current stimulation could increase MBI and FMA,improve gait spatio-temporal parameters and lower limb joint motion parameters,and correct abnormal gait in patients with cerebral infarction.
基金supported by National Science Foundation for Distinguished Young Scholoars, China (Grant No. 51125020)Program for New Century Excellent Talents in University, China
文摘The equivalent mechanism of the system is often considered as one specific mechanism in most existing studies of multi-legged robots, however the equivalent mechanism is varying while the robot moves on the ground. Four typical tripod period gaits of a radial symmetrical six-legged robot are analyzed. Similar to the metamorphic mechanism, the locomotion of multi-legged robot is considered as a series of varying hybrid serial-parallel mechanisms by assuming the constraints of the feet on the ground with hinges. One gait cycle is divided into several periods, and in different walking period there is a specific equivalent mechanism corresponding to it, and the walking process of multi-legged robot is composed by these series of equivalent mechanisms. Walking performance can be got by analyzing these series of equivalent mechanisms. Kinematics model of the equivalent mechanism is established, workspaces of equivalent mechanisms are illustrated by simulation and a concept of static stability workspace is proposed to evaluate the static stability of these four gaits. A new method to calculate the stride length of multi-legged robots is presented by analyzing the relationship between the workspace of two adjacent equivalent parallel mechanisms in one gait cycle. The stride lengths of four gaits are given by simulations. Comparison of stride length and static stability among these four typical tripod gaits are given. It has been proved that mixed gait and insect-wave gait II have better static stability than mammal kick-off gait and insect-wave gait I. Insect-wave gait II displays its advantage on stride length while the height of robot body lower than 87 mm, mammal kick-off gait has superiority on stride length while the height of robot body higher than 115 mm, and insect-wave gait I shows its shortcoming in stride length. The proposed method based on metamorphic theory and combining the footholds and body height of robot provides a new method to comprehensive analyze the performance of multi-legged robot.
基金Supported by National Natural Science Foundation of China(Grant Nos.51775011,91748201)
文摘The previous research regarding the gait planning of quadruped robot focuses on the sequence for lifting o and placing the feet, but neglects the influence of body height. However, body height a ects gait performance significantly, such as in terms of the stride length and stability margin. We herein study the performance of a quadruped robot using the equivalent mechanism concept based on metamorphosis. Assuming the constraints between standing feet and the ground with hinges, the ground, standing legs and robot body are considered as a parallel mechanism, and each swing leg is regarded as a typical serial manipulator. The equivalent mechanism varies while the robot moves on the ground. One gait cycle is divided into several periods, including step forward stages and switching stages. There exists a specific equivalent mechanism corresponding to each gait period. The robot's locomotion can be regarded as the motion of these series of equivalent mechanisms. The kinematics model and simplified model of the equivalent mechanism is established. A new definition of the multilegged robot stability margin, based on friction coe cient, is presented to evaluate the robot stability. The stable workspaces of the equivalent mechanism in the step forward stage of trotting gait under di erent friction coe cients are analyzed. The stride length of the robots is presented by analyzing the relationship between the stable workspaces of the equivalent mechanisms of two adjacent step forward stages in one gait cycle. The simulation results show that the stride length is larger with increasing friction coe cient. We herein propose a new method based on metamorphosis, and an equivalent mechanism to analyze the stability margin and stable workspace of the multilegged robot.
文摘In this work, a total of 322 tests were taken on young volunteers by performing 10 different falls, 6 different Activities of Daily Living (ADL) and 7 Dynamic Gait Index (DGI) tests using a custom-designed Wireless Gait Analysis Sensor (WGAS). In order to perform automatic fall detection, we used Back Propagation Artificial Neural Network (BP-ANN) and Support Vector Machine (SVM) based on the 6 features extracted from the raw data. The WGAS, which includes a tri-axial accelerometer, 2 gyroscopes, and a MSP430 microcontroller, is worn by the subjects at either T4 (at back) or as a belt-clip in front of the waist during the various tests. The raw data is wirelessly transmitted from the WGAS to a near-by PC for real-time fall classification. The BP ANN is optimized by varying the training, testing and validation data sets and training the network with different learning schemes. SVM is optimized by using three different kernels and selecting the kernel for best classification rate. The overall accuracy of BP ANN is obtained as 98.20% with LM and RPROP training from the T4 data, while from the data taken at the belt, we achieved 98.70% with LM and SCG learning. The overall accuracy using SVM was 98.80% and 98.71% with RBF kernel from the T4 and belt position data, respectively.
基金provided by the Educational Bureau of Liaoning Province,No. 2009A671
文摘An experiment was carried out in the key laboratory for Technique Diagnosis and Function Assessment of Winter Sports of China to investigate the differences in gait characteristics between healthy children and children with spastic hemiplegic cerebral palsy.With permission of their parents,200 healthy children aged 3 to 6 years in the kindergarten of Northeastern University were enrolled in this experiment.Twenty children aged 3 to 6 years with spastic hemiplegic cerebral palsy from Shengjing Hospital,China were also enrolled in this experiment.Standard data were collected by simultaneously recording gait information from two digital cameras.DVracker was used to analyze the standard data.The children with hemiplegic cerebral palsy had a longer gait cycle,slower walking speed,and longer support phase than did the healthy children.The support phase was longer than the swing phase in the children with hemiplegic cerebral palsy.There were significant differences in the angles of the hip,knee,and ankle joint between children with cerebral palsy and healthy children at the moment of touching the ground and buffering,and during pedal extension.Children with hemiplegic cerebral palsy had poor motor coordination during walking,which basically resulted in a short stride,high stride frequency to maintain speed,more obvious swing,and poor stability.
文摘In this paper, a comparative analysis of walking patterns during different cognitive states is conducted, followed by the classification of our database into Fallers and Non-fallers;by Fallers we describe subjects with repeated falling history. Vertical Ground Reaction Forces (VGRF) acquired from underneath the heel and toes of both feet are processed and analyzed for that endeavor. The subjects underwent three levels of tasks: 1) Single task: Walking at self-selected-speed (MS), 2) Dual task: Walking while performing a verbal fluency task (MF) and 3) Complex Dual task: Walking while counting backwards (MD).The ultimate objective of our research is fall prediction among the elderly by characterizing the variation of time-domain feature of Gait signals. For that, walking VGRF is analyzed and tested for the existence of indicators of the effect of dual task on subject falling susceptibility, whether parametric or pattern-wise analysis. As a result to our work, dual task in Fallers VGRF signals were recognized at 74% while at those non-fallers were recognized at 85%. Most importantly, subjects with history of fall have shown more potential to change the way they walk while performing mathematical cognitive task.
文摘<div style="text-align:justify;"> With the development of medicine and the improvement of people’s living standards, the issue of rehabilitation is getting more and more attention. Gait rehabilitation provides a brand-new treatment method for patients with walking disfunction. It is currently recognized as an advanced rehabilitation medical method in the world. In recent years, the number of patients suffering from dyskinesias in the lower limbs in China has been increasing, and the society's demand for walking rehabilitation treatment is also increasing. The emergence of gait rehabilitation solves the problem of fewer therapists and more patients, reduces the intensity of the therapist’s work, and has the incomparable advantage that traditional rehabilitation methods lack. However, because there are no mature related products in China at present, and the prices of foreign products are very expensive, domestic medical institutions have not yet put them into practice. Accelerating the development of gait re-habilitation equipment is of great significance for improving China’s medical level, improving the quality of life of patients, and reducing social burden. Usually, high-precision optical sensors are installed on human limbs or using high-speed cameras to capture motion. However, due to the high cost of the equipment, the relative high price of image processing software when processing the collected motion data. In this paper, the acceleration sensors are installed on the human body and the data in a gait cycle can be obtained. After smoothing, using it as the input signal for gait feature extraction and classification. In order to classify normal gait and abnormal gait for evaluation and better walking rehabilitation. </div>
基金the Chinese National Education Committee for supporting his visit to UK in 1995.
文摘In clinical assessment or sports exercise,it is common that a subject is required to repeat a specific per- formance so that a stable movement pattern is obtained and analysed.In practice,however,the trials done by a sub- ject vary more or less,depending on the psychological or physical conditions.Some of the trials can be used as rep- resentatives of the stable movement pattern,and some not.Therefore,there is a demand for a new method to identify which trials/curves are similar.The traditional methods used to assess curve similarity are not perfectly suitable for the case where there are only a few of trials available.This study proposes a similarity-distance coefficient to assess the similarity of curves/trials.A group of designed curves are used to validate the coefficient.The results show that given joint kinematic data during gait as examples,the proposed coefficient can be used to quantitatively evaluate the similarity of trials,and thus find which trials would be representative (s) for the gait investigated.The proposed method could be applied in various situations where repeat movements have to be measured and analysed.
文摘Introduction: gait analysis of a subject with total hip replacement is described. Objective: instrumental gait analysis of a subject 12 years after the total hip arthroplasty. Materials and Methods: in a movement analysis laboratory, locomotion studies were carried out at freely chosen walking speed by a 64-year-old subject, obtaining kinematic, kinetic and surface electromyographic data in time and space. All measurements were assessments by applying walking protocols on a straight surface of 8 m long. Results: abnormal slight activations of semitendinosus and tibialis anterior muscles, of the left limb, were observed throughout the gait cycle, no spatiotemporal parameters far from normal values were detected. Conclusions: it was possible to obtain an exhaustive analysis of the parameters associated with the gait of a subject after 12 years of total hip arthroplasty.
基金National Key R&D Program of China(2017YFC0110705)。
文摘Purpose:Robot-assisted technology is a forefront of surgical innovation that improves the accuracy of total knee arthroplasty (TKA).But whether the accuracy of surgery can improve the clinical efficacy still needs further research.The purpose of this study is to perform three-dimensional (3D) analysis in the early postoperative period of patients who received robot-assisted total knee arthroplasty (RATKA),and to study the trend of changes in gait parameters after RATKA and the correlation with the early clinical efficacy.Methods:Patients who received RATKA in the Center of Joint Surgery,the First Hospital Affiliated to Army Military Medical University from October 2020 to January 2021 were included.The imaging parameters,i.e.,hip-knee-ankle angle,lateral distal femoral angle,medial proximal tibial angle,posterior condylar angle were measured 3 months post-TKA.The 3D gait analysis and clinical efficacy by Western Ontario Mac Master University Index (WOMAC) score were performed pre-TKA,3 and 6 months post-TKA.The differences in spatiotemporal parameters of gait,kinetic parameters,and kinematic parameters of the operated limb and the contralateral limb were compared.The correlation between gait parameters and WOMAC scores was analyzed.Paired samplet-test and Wilcoxon rank-sum test were used to analyze the difference between groups,and Spearman correlation coefficient was used to analyze the correlation.Results:There were 31 patients included in this study,and the imaging indexes showed that all of them returned to normal post-TKA.The WOMAC score at 3 months post-TKA was significantly lower than that pre-TKA,and there was no significant difference between at 3 and 6 months.The 3D gait analysis results showed that the double support time of the operated limb reduced at 3 and 6 months (allp < 0.05),the maximum extension and maximum external rotation of the knee joint increased at stance phase,and the maximum flexion angle,the range of motion and the maximum external rotation increased at swing phase.Compared with the preoperative data,there were significant improvements (allp < 0.05).Compared with the contralateral knee joint,the maximum external rotation of the knee joint at swing phase was smaller than that of the contralateral side,and the maximum flexion and extension moment was greater than that of the contralateral knee.The maximum external rotation moment of the joint was greater than that of the contralateral knee joint (p < 0.05).There was a negative correlation between the single support time pre-TKA and the WOMAC score at 3 months (p = 0.017),and the single support time at 3 months was negatively correlated with the WOMAC score at 6 months (p = 0.043).The cadence at 6 months was negatively correlated with the WOMAC score at 6 months (p = 0.031).The maximum knee extension at stance phase at 6 months was negatively correlated with the WOMAC score at 6 month (p = 0.048).The maximum external rotation at stance phase at 6 months was negatively correlated with the WOMAC score at 6 months (p = 0.024).Conclusion:The 3D gait analysis of RATKA patients is more sensitive than WOMAC score in evaluating the clinical efficacy.Trend of changes in gait parameters shows that the knee joint support,flexion and extension function,range of motion,external rotation and varus deformity moment of the patient were significantly improved at 3 months after surgery,and continued to 6 months after surgery.Compared with the contralateral knee,the gait parameters of the operated limb still has significant gaps in functionality,such as the external rotation and flexion and extension.The single support time,cadence,knee extension,and knee external rotation of the operated limb have a greater correlation with the postoperative WOMAC score.Postoperative rehabilitation exercises should be emphasized,which is of great value for improving the early efficacy of RATKA.
基金supported by the National Natural Science Foundation of China(Grant no.51975126)the China Postdoctoral Science Foundation(Grant no.2021M700882)+1 种基金the Frontier and Key Technology Innovation Funds of Guangdong Province(Grant no.2017B050506008)the Guangdong Yangfan Program for Innovative and Entrepreneurial Teams(Grant no.2017YT05G026).
文摘Soft climbing/crawling robots have been attracting increasing attention in the soft robotics community,and many prototypes with basic locomotion have been implemented.Most existing soft robots achieve locomotion by planar bending deformation and lack sufficient mobility.Enhancing the mobility of soft climbing/crawling robots is still an open and challenging issue.To this end,we present a novel pneumatic leech-like soft robot,Leechbot,with both bending and stretching deformation for locomotion.With a morphological structure,the robot consists of a three-chambered actuator in the middle for the main motion,two chamber-net actuators that act as ankles,and two suckers at the ends for anchoring on surfaces.The peristaltic motion for locomotion is implemented by body stretching,and direction changing is achieved by body bending.Due to the novel design and two deformation modes,the robot can make turns and transit between different surfaces;the robot,hence,has excellent mobility.The development of the robot prototype is presented in detail in this paper.To control its motion,tests were carried out to determine the relationship between step length and air pressure as well as the relationship between motion speed and periodic delay time.A kinematic model was established,and the kinematic mobility and surface transitionability were analyzed.Gait planning based on the inflating sequence of the actuating chambers is presented for straight crawling,turn making,and transiting between surfaces and was verified by a series of experiments with the prototype.The results show that a high mobility in soft climbing/crawling robots can be achieved by a novel design and by proper gait planning.
基金supported in part by the National Key Research and Development Program of China[Grant No.2020AAA0108900]the National Natural Science Foundation of China[No.91948201,62003190,62203268,61973185]+1 种基金the Open Research Projects of Zhejiang Lab(No.2022NB0AB06)the National Natural Science Foundation of Shandong Province of China[No.ZR2022QF027].
文摘Quadruped animals in the nature realize high energy efficiency locomotion by automatically changing their gait at different speeds.Inspired by this character,an efficient adaptive diagonal gait locomotion controller is designed for quadruped robot.A unique gait planning method is proposed in this paper.As the speed of robot varies,the gait cycle time and the proportion of stance and swing phase of each leg are adjusted to form a variety of gaits.The optimal joint torque is calculated by the controller combined with Virtual Model Control(VMC)and Whole-Body Control(WBC)to realize the desired motion.The gait and step frequency of the robot can automatically adapt to the change of speed.Several experiments are done with a quadruped robot made by our laboratory to verify that the gait can change automatically from slow-trotting to flying-trot during the period when speed is from 0 to 4 m/s.The ratio of swing phase is from less than 0.5 to more than 0.5 to realize the running motion with four feet off the ground.Experiments have shown that the controller can indeed consume less energy when robot runs at a wide range of speeds comparing to the basic controller.