Neural Network Robust Control Based on Computed Torque for Lower Limb Exoskeleton

The lower limb exoskeletons are used to assist wearers in various scenarios such as medical and industrial settings.Complex modeling errors of the exoskeleton in different application scenarios pose challenges to the robustness and stability of its control algorithm.The Radial Basis Function(RBF)neural network is used widely to compensate for modeling errors.In order to solve the problem that the current RBF neural network controllers cannot guarantee the asymptotic stability,a neural network robust control algorithm based on computed torque method is proposed in this paper,focusing on trajectory tracking.It innovatively incorporates the robust adaptive term while introducing the RBF neural network term,improving the compensation ability for modeling errors.The stability of the algorithm is proved by Lyapunov method,and the effectiveness of the robust adaptive term is verified by the simulation.Experiments wearing the exoskeleton under different walking speeds and scenarios were carried out,and the results show that the absolute value of tracking errors of the hip and knee joints of the exoskeleton are consistently less than 1.5°and 2.5°,respectively.The proposed control algorithm effectively compensates for modeling errors and exhibits high robustness.

Model Parameters Identification and Backstepping Control of Lower Limb Exoskeleton Based on Enhanced Whale Algorithm

Exoskeletons generally require accurate dynamic models to design the model-based controller conveniently under the human-robot interaction condition.However,due to unknown model parameters such as the mass,moment of inertia and mechanical size,the dynamic model of exoskeletons is difficult to construct.Hence,an enhanced whale optimization algorithm(EWOA)is proposed to identify the exoskeleton model parameters.Meanwhile,the periodic excitation trajectories are designed by finite Fourier series to input the desired position demand of exoskeletons with mechanical physical constraints.Then a backstepping controller based on the identified model is adopted to improve the human-robot wearable comfortable performance under cooperative motion.Finally,the proposed Model parameters identification and control are verified by a two-DOF exoskeletons platform.The knee joint motion achieves a steady-state response after 0.5 s.Meanwhile,the position error of hip joint response is less than 0.03 rad after 0.9 s.In addition,the steady-state human-robot interaction torque of the two joints is constrained within 15 N·m.This research proposes a whale optimization algorithm to optimize the excitation trajectory and identify model parameters.Furthermore,an enhanced mutation strategy is adopted to avoid whale evolution’s unsatisfactory local optimal value.

Personalized Lower Limb Gait Reconstruction Modeling Based on RFA-ProMP

Personalized gait curves are generated to enhance patient adaptability to gait trajectories used for passive training in the early stage of rehabilitation for hemiplegic patients.The article utilizes the random forest algorithm to construct a gait parameter model,which maps the relationship between parameters such as height,weight,age,gender,and gait speed,achieving prediction of key points on the gait curve.To enhance prediction accuracy,an attention mechanism is introduced into the algorithm to focus more on the main features.Meanwhile,to ensure high similarity between the reconstructed gait curve and the normal one,probabilistic motion primitives(ProMP)are used to learn the probability distribution of normal gait data and construct a gait trajectorymodel.Finally,using the specified step speed as input,select a reference gait trajectory from the learned trajectory,and reconstruct the curve of the reference trajectoryusing the gait keypoints predictedby the parametermodel toobtain the final curve.Simulation results demonstrate that the method proposed in this paper achieves 98%and 96%curve correlations when generating personalized lower limb gait curves for different patients,respectively,indicating its suitability for such tasks.

Epidemiological, Clinical and Paraclinical Profile of Osteoarthritis of the Lower Limbs in Obese Patients at the Cocody University Teaching Hospital

Objective: To describe the epidemiological, clinical and paraclinical characteristics of osteoarthritis of the lower limbs in obese patients at the Cocody University Teaching Hospital. Methodology: This was an analytical cross-sectional study carried out in the rheumatology department of the Cocody UTH in Abidjan (Ivory Coast) from March 1 to April 30 2023. Patients who came for rheumatology consultation presenting with mechanical arthralgia of the lower limbs, who were obese, had radiographic images were included. All patients without radiographic images were excluded. Obesity was defined as a body mass index (BMI) greater than or equal to 30 kg/m. The Chi2 test was used to compare proportions and determine the existence of associations between osteoarthristis and obesity, obesity severity and radiographic stage of osteoarthritis as well as the functional impact. A p-value below a predefined threshold (p = 0,05) indicates a significant relationship between the variables. Result: Out of 185 patients received for osteoarthritis of the lower limbs during the study period, 136 were obese (74%). There were 115 women (84.6%) with an average age of 56.03 with a standard deviation of 12.72 years (extremes: 22 and 84 years). The main socio-professional category was the informal sector (30%). The majority of patients had a low socio-economic level (80.2%) and lived in urban areas (92.6%). The most common past medical history was hypertension (33.08%) followed by peptic ulcer disease (16.91%). Patients had a body mass index class 1 (81.6%), class 2 (15.40%) and class 3 (2.90%). The average duration of symptom progression until diagnosis was 11 months. Genu varum was the main static disorder (56.10%) and the knee joint was the dominant topography (90.4%) with a bilateral localization (80%). The average Lequesne index was greater than 8 (59.5%). The Kellgren and Lawrence radiographic stages were stage 1 (9.20%), stage 2 (46.90%), stage 3 (29.20%) and stage 4 (6.90%). The Obesity severity was significantly associated with osteoarthritis of the knee (p = 0.042). There was no statistically significant association between obesity severity and radiographic stage of osteoarthritis (p = 0.163) or functional impact (p = 0.180). Conclusion: Osteoarthritis of the lower limbs affected obese women and was dominated by stage 2 osteoarthritis of the knee (Kellgren and Lawrence). There is an association between the severity of obesity and osteoarthritis of the knee.

Intervention Effect of Lower Limb Rehabilitation Robot with Task-Oriented Training on Stroke Patients and Its Influence on KFAROM Score

Objective: To explore the effect of lower limb rehabilitation robot combined with task-oriented training on stroke patients and its influence on KFAROM score. Methods: 100 stroke patients with hemiplegia admitted to our hospital from January 2023 to December 2023 were randomly divided into two groups, the control group (50 cases) was given task-oriented training assisted by nurses, and the observation group (50 cases) was given lower limb rehabilitation robot with task-oriented training. Lower limb balance, lower limb muscle strength, motor function, ankle function, knee flexion range of motion and walking ability were observed. Results: After treatment, the scores of BBS, quadriceps femoris and hamstrings in the observation group were significantly higher than those in the control group (P Conclusion: In the clinical treatment of stroke patients, the combination of task-oriented training and lower limb rehabilitation robot can effectively improve the lower limb muscle strength, facilitate the recovery of balance function, and have a significant effect on the recovery of motor function, which can improve the walking ability of stroke patients and the range of motion of knee flexion, and achieve more ideal therapeutic effectiveness.

Assistive Devices and Clothing: Exploring Adaptive Clothing Needs for Women with Lower Limb Prostheses Using the FEA Model

This study aimed to comprehensively investigate the essential considerations in designing adaptive clothing for women with lower limb prostheses in Saudi Arabia. Employing a qualitative methodology, the research entailed semi-structured, in-depth interviews with women utilizing lower limb prostheses and prosthetic specialists. This approach was selected to unearth pivotal design prerequisites and comprehend the specific challenges these women encounter within the realm of clothing. The utilization of selective sampling facilitated the collection of intricate and valuable insights. A Functional, Expressive, and Aesthetic (FEA) User Needs model was utilized to scrutinize participant feedback. Functional requisites encompass ease of dressing and undressing, accessibility to the prosthetic limb, comfort, mobility with the prosthesis, and appropriate fit. Additionally, participants highlighted various expressive needs, including privacy preservation, modesty, camouflaging disability appearances, maintaining alignment with non-disabled women’s fashion, and considerations about the aesthetic aspects of garments.

A Clinical Randomized Controlled Study of Low-Frequency rTMS Therapy on Lower Limb Motor Dysfunction after Stroke

Objective:To investigate the efficacy and safety of low-frequency repetitive transcranial magnetic stimulation(rTMS)for the treatment of lower limb motor dysfunction after stroke.Methods:A total of 96 patients with stroke and lower limb motor dysfunction were enrolled in this study,and were randomly divided into the experimental group and the sham stimulation group using the method of calculator-generated random numbers.Both groups received conventional medication and rehabilitation therapy.The experimental group received 4 weeks of 1 Hz rTMS treatment in the primary cortical motor area(M1)of the healthy side,with the treatment coil tangent to the skull surface;the sham stimulation group underwent the same procedures as the experimental group,but the treatment coil was perpendicular to the skull surface instead.Lower-extremity subscale of the Fugl-Meyer Assessment(FMA-LE),Berg Balance Scale(BBS),gait analysis,and lower-extremity surface electromyography(LESEM)were performed in both groups before and after rTMS treatment.Results:All 96 patients completed the test with no shedding and no adverse reactions.After treatment,the FMA-LE score and BBS score of the 2 groups of patients were significantly improved as compared with the pre-treatment(P<0.05),and the TUG test time was reduced as compared with the pre-treatment(P<0.05).The true stimulation group had greater improvement in all assessment indexes than that of the sham stimulation group(P<0.05).After treatment,the electromyographic activity of the tibialis anterior and rectus femoris muscles in the true simulation group improved significantly.The step length,step speed,and step frequency were also significantly improved in both groups after treatment,and the symmetrical ratio of step length and support time was reduced(P<0.05).Comparison between the groups revealed that the true simulation group significantly improved after rTMS treatment as compared to the sham stimulation group(P<0.05).Conclusion:1Hz rTMS treatment safely and effectively improved motor and balance function in patients with post-stroke lower limb motor dysfunction.

Lower limb amputation rehabilitation status in India: A review

Rehabilitation of lower limb amputation in developing countries is quite challenging.Though there are basic to highly advanced prostheses available in India,the set-up is still facing difficulties in developing countries.Prosthetic management is difficult due to lack of availability of prostheses and reduced affordability among low income populations.In this review we highlighted the lower limb amputation and prosthetic rehabilitation status in India.Currently,India is advancing well in the rehabilitation field,but further studies are required to provide more evidence and recommendation.

Equalisation of Lower Limb Length in Young Adults Using Internal Osteosynthesis: A Case Report of 22 Patients

Introduction: Inequality in the length of the lower limbs has an impact on the stability and function of the musculoskeletal system because of the imbalance it causes in our bodies. Several treatment modalities were used by practitioners. The aim of this study was to evaluate the anatomical and functional results of length equalisation of the lower limbs using internal osteosynthesis in the Orthopaedic and Traumatological Surgery Department of the Amirou Boubacar Diallo National Hospital in Niamey. Patients and method: This was a retrospective, prospective study of 22 patients from January 2010 to November 2015, a period of 5 years. The patients concerned were aged at least 18 years and had undergone a femoral shortening osteotomy not exceeding 5 cm on the contralateral healthy limb with a screw plate as the internal osteosynthesis device. Results: The average age of our patients was 24.18 years (18 to 48 years). The etiologies of these length inequalities were: vascular 54.55% (n = 12), post-traumatic 27.27% (n = 6), post-infectious 13.64% (n = 3) and neuromuscular 4.54% (n = 1). The mean length inequality of our patients was 4.93 cm, with extremes ranging from 4 to 8 cm. At an average follow-up of 6.5 months (6 to 24 months), our functional results were satisfactory overall. Discussion: Despite the significant nature of our initial inequalities, which were moderate and severe, we ended up with slight inequalities or even total correction for some of our patients. Conclusion: Inequality in the length of the lower limbs is a handicap that requires appropriate management.

Knowledge of Patients and Their Accompanying Persons about Obliterative Arteriopathy of the Lower Limbs at Conakry University Hospital in 2022

Introduction: Obliterative arterial disease of the lower limbs is a marker of advanced atherosclerosis. It is one of the world’s most common cardiovascular diseases, present in one in five people over the age of 60, and carries an increased risk of morbidity and mortality. The aim of this study was to assess the knowledge of patients and their carers about obliterative arteriopathy of the lower limbs at Conakry University Hospital. Material and Methods: We conducted a descriptive cross-sectional study lasting 3 months, from March 12 to June 12, 2022 in the hospitals of the University Hospital of Conakry (Donka and Ignace Deen). Following free and informed consent, they were interviewed on the basis of a pre-established questionnaire. Socio-demographic data (age, gender, level of education) were collected, and knowledge of obliterative arterial disease of the lower limbs. Results: The study involved 159 people, comprising 106 patients (66.66%) and 53 accompanying persons (33.34%) in the hospitals of the University Hospital of Conakry (Donka and Ignace Deen). The 60 to 79 age group was the most represented (44.7%), with an average age of 55.4 ± 15.9 years and extremes of 20 to 84 years. Half (47.8%) had not attended school, and almost all (96.4%) of those who had attended school had a low level of education (primary and secondary). Almost all of them (91.2%) had never heard of AOMI. Only 5% identified at least one risk factor, diabetes, hypertension and smoking. Amputation was the most frequently identified complication. About 98% did not know that AOMI is associated with myocardial infarction and stroke, and 93.7% did not know of any complications. Almost all the participants (99.4%) had poor knowledge of the following complications. Conclusion: Obliterative arterial disease of the lower limbs could be prevented or delayed by screening and controlling risk factors. Our results show a huge deficit in knowledge of this pathology, including risk factors, preventive measures, clinical signs and complications among patients and their relatives. A study conducted outside the hospital environment would provide a better understanding of the extent to which the general population is unaware of this disease.

Risk Factors for Lower Extremity Amputation among Diabetic Patients with Diabetic Foot Gangrene in ATBUTH, Bauchi

Background: Diabetic mellitus was described as an evolving global epidemic of the twenty-first century, due to the exponential rise in the number of people with the condition. Lower extremity amputation is one of the common complications of diabetes. With increase in the number of people with diabetes there will also be increase in the number of diabetics going for lower extremity amputation, increasing both the financial as well as psychologic burden of treatment. Methodology: A prospective cross-sectional study of all diabetic patients going for lower extremity amputation will be done. All the patients with advanced diabetic foot syndrome needing lower extremity amputation are enrolled (Wagener stage IV and V), both through the clinic and emergency center. Informed consent is obtained from the patient after which data are collected using a structured questionnaire. All the investigation results of the patients were also documented. Data collected are analyzed using the SPSS version 29. Chi-square and student t-test were used to measure significant relationship between the variables at 95% confident interval. Results: Within the period of study, which extends from 1st January 2022 to 1st of January 2024, a total of 171 patients were recruited. All diabetic patients with diabetic foot Wagener grade IV and V who presented to the clinic or emergency department were enrolled in the study. We found a significant relationship between gender, previous procedure on the affected limb or amputation of the contralateral limb, knowledge of foot care among diabetics and risk of amputation. There was, however, no statistically significant relationship between. There is no statistically significance relationship between the level of education, occupation, presence of co-morbidity with the risk of amputation among diabetic patients with foot syndrome. Conclusion: Previous lower limb procedure/amputation, male gender, paucity of knowledge on foot care, prolonged duration of the disease and method of treatment are important risk factors for the risk of amputation among diabetic patients with diabetic foot syndrome.

A Review on Lower Limb Rehabilitation Exoskeleton Robots

Lower limb rehabilitation exoskeleton robots integrate sensing, control, and other technologies and exhibit the characteristics of bionics, robotics, information and control science, medicine, and other interdisciplinary areas. In this review, the typical products and prototypes of lower limb exoskeleton rehabilitation robots are introduced and stateof-the-art techniques are analyzed and summarized. Because the goal of rehabilitation training is to recover patients’ sporting ability to the normal level, studying the human gait is the foundation of lower limb exoskeleton rehabilitation robot research. Therefore, this review critically evaluates research progress in human gait analysis and systematically summarizes developments in the mechanical design and control of lower limb rehabilitation exoskeleton robots. From the performance of typical prototypes, it can be deduced that these robots can be connected to human limbs as wearable forms;further, it is possible to control robot movement at each joint to simulate normal gait and drive the patient’s limb to realize robot-assisted rehabilitation training. Therefore human–robot integration is one of the most important research directions, and in this context, rigid-flexible-soft hybrid structure design, customized personalized gait generation, and multimodal information fusion are three key technologies.

Structure Design of Lower Limb Exoskeletons for Gait Training

Due to the close physical interaction between human and machine in process of gait training, lower limb exoskeletons should be safe, comfortable and able to smoothly transfer desired driving force/moments to the patients. Correlatively, in kinematics the exoskeletons are required to be compatible with human lower limbs and thereby to avoid the uncontrollable interactional loads at the human-machine interfaces. Such requirement makes the structure design of exoskeletons very difficult because the human-machine closed chains are complicated. In addition, both the axis misalignments and the kinematic character difference between the exoskeleton and human joints should be taken into account. By analyzing the DOF（degree of freedom） of the whole human-machine closed chain, the human-machine kinematic incompatibility of lower limb exoskeletons is studied. An effective method for the structure design of lower limb exoskeletons, which are kinematically compatible with human lower limb, is proposed. Applying this method, the structure synthesis of the lower limb exoskeletons containing only one-DOF revolute and prismatic joints is investigated; the feasible basic structures of exoskeletons are developed and classified into three different categories. With the consideration of quasi-anthropopathic feature, structural simplicity and wearable comfort of lower limb exoskeletons, a joint replacement and structure comparison based approach to select the ideal structures of lower limb exoskeletons is proposed, by which three optimal exoskeleton structures are obtained. This paper indicates that the human-machine closed chain formed by the exoskeleton and human lower limb should be an even-constrained kinematic system in order to avoid the uncontrollable human-machine interactional loads. The presented method for the structure design of lower limb exoskeletons is universal and simple, and hence can be applied to other kinds of wearable exoskeletons.

Successful endovascular treatment in patients with acute thromboembolic ischemia of the lower limb including the crural arteries

AIM To examine the efficacy and safety of the 6 French(6F) Rotarex~S catheter system in patients with acute limb ischemia(ALI) involving thromboembolic occlusion of the proximal and mid-crural vessels.METHODS The files of patients in our department with ALI between 2015 and 2017 were examined. In seven patients, the Rotarex~S catheter was used in the proximal segment of the crural arteries. Data related to the clinical examination, Doppler sonography, angiography and followup from these patients were further used for analysis.RESULTS Two patients(29%) had thrombotic occlusion of the common femoral artery, and the remaining five exhibited thrombosis of the superficial femoral artery and popliteal artery. Mechanical thrombectomy was performed in all cases using a 6F Rotarex~S catheter. Additional Rotarex~S catheter thrombectomy due to remaining thrombus formation with no reflow was performed in the anterior tibial artery in two of seven cases(29%), in the tibiofibular tract and posterior tibial artery in two of seven cases(29%) and in the tibiofibular tract and fibular artery in the remaining three of seven cases(43%). Ischemic symptoms resolved promptly in all, and none of the patients experienced a procedural complication, such as crural vessel dissection, perforation or thrombus embolization.CONCLUSION Mechanical debulking using the 6F Rotarex~S catheter system may be a safe and effective treatment option in case of thrombotic or thromboembolic occlusion of the proximal and mid-portion of crural arteries.

Lower limb stress fractures in sport:Optimising their management and outcome

Stress fractures in sport are becoming increasing more common,comprising up to 10%of all of sporting injuries.Around 90%of such injuries are located in the lower limb.This articles aims to define the optimal management of lower limb stress fractures in the athlete,with a view to maximise return rates and minimise return times to sport.Treatment planning of this condition is specific to the location of the injury.However,there remains a clear division of stress fractures by"high"and"low"risk."Low risk"stress fractures are those with a low probability of fracture propagation,delayed union,or non-union,and so can be managed reliably with rest and exercise limitation.These include stress fractures of the PosteroMedial Tibial Diaphysis,Metatarsal Shafts,Distal Fibula,Medial Femoral Neck,Femoral Shaft and Calcaneus."High risk"stress fractures,in contrast,have increased rates of fracture propagation,displacement,delayed and non-union,and so require immediate cessation of activity,with orthopaedic referral,to assess the need for surgical intervention.These include stress fractures of the Anterior Tibial Diaphysis,Fifth Metatarsal Base,Medial Malleolus,Lateral Femoral Neck,Tarsal Navicular and Great Toe Sesamoids.In order to establish the optimal methods for managing these injuries,we present and review the current evidence which guides the treatment of stress fractures in athletes.From this,we note an increased role for surgical management of certain high risk stress fractures to improve return times and rates to sport.Following this,key recommendations are provided for the management of the common stress fracture types seen in the athlete.Five case reports are also presented to illustrate the application of sportfocussed lower limb stress fracture treatment in the clinical setting.

Adaptive Robust Control for a Lower Limbs Rehabilitation Robot Running Under Passive Training Mode

This paper focuses on the problem of the adaptive robust control of a lower limbs rehabilitation robot(LLRR) that is a nonlinear system running under passive training mode. In reality, uncertainties including modeling error, initial condition deviation, friction force and other unknown external disturbances always exist in a LLRR system. So, it is necessary to consider the uncertainties in the unilateral man-machine dynamical model of the LLRR we described. In the dynamical model, uncertainties are(possibly fast) time-varying and bounded. However, the bounds are unknown. Based on the dynamical model, we design an adaptive robust control with an adaptive law that is leakagetype based and on the framework of Udwadia-Kalaba theory to compensate for the uncertainties and to realize tracking control of the LLRR. Furthermore, the effectiveness of designed control is shown with numerical simulations.

Versatility of Reverse Sural Fasciocutaneous Flap for Reconstruction of Distal Lower Limb Soft tissue Defects

Summary： In this study we present our experiences with the reverse sural fasciocutaneous flap to reconstruct the distal lower limb soft tissue defects caused by traumatic injuries. These flap graftings were carried out from Oct. 2010 to Dec. 2012 in our department. The series consisted of 36 patients, including 21 men and 15 women with an average age of 46.2 years （14-83 years） and with a medium followp period of 18 months （12-24 months）. Of all the cases of acute trauma, there were 10 eases of trauma of distal tibia, 9 cases of trauma of perimalleolus, and 17 cases of trauma of midfoot and forefoot. Related risk factors in the patients were diabetes （2 cases）, advanced age （〉65 years, 3 cases） and ciga- rette smoking （6 cases）. The reverse flow sural island flap irrigation depended on lower perforators of the peroneal artery. The fasciocutaneous pedicle was 3-4 cm in width and the anatomical structures consisted of the superficial and deep fascia, the sural nerve, short saphenous vein, superficial sural artery together with an islet of subcutaneous cellular tissue and skin. The most proximal border of the flap was only 1.5 cm away from the popliteal skin crease and the pivot point was 5-7 cm above the tip of the lateral malleolus. All the flaps survived. No arterial crisis occurred in any case. The venous congestion occurred in 2 cases and got better after raising the limbs and bloodletting. Only in an old man, 1.5 cm necrosis of distal margin of his flap occurred and finally healed after continuous dressing change. One-stage skin grafting was performed, and all the donor sites were sutured and successfully healed. It was concluded that the reverse sural fasciocutaneous flap is safe and reliable to extend to the proximal third even near the popliteal skin crease. We also concluded this flap can be safely and efficiently used to treat patients with large and far soft-tissue defects from the distal leg to the forefoot with more versatility and it is easier to reach the recipient sites.

Slacklining and stroke: A rehabilitation case study considering balance and lower limb weakness

To ascertain the effectiveness of slacklining as a supplementary therapy for elderly stroke patients who are functionally non-progressing. This case study involved an 18-mo prospective observation of the management of an 87-year-old female stroke-patient of the left hemisphere with reduced balance, reduced lower limb muscular activation, hypertonia, and concurrent postural deficits. This entailed the initial acute care phase through to discharge to home and 18-mo final status in her original independent living setting. The introduction of slacklining as an adjunct therapy was made 12 mo post incident. Slacklining involves balance retention on a tightened band where external environmental changes cause a whole-body dynamic response to retain equilibrium. It is a complex neuromechanical task enabling individualized self-developed response strategies to be learned and adapted. This facilitates the innate process of balance retention, lower-limb and core muscle activation, and stable posture through a combination of learned motor skills and neurological system down regulation. Individuals adopt and follow established sequential motor learning stages where the acquired balance skillsare achieved in a challenging composite-chain activity. Slacklining could be considered an adjunct therapy for lower limb stroke rehabilitation where function is compromised due to decreased muscle recruitment, decreased postural control and compromised balance. Initial inpatient rehabilitation involved one-month acute-care, one-month rehabilitation, and one-month transitional care prior to home discharge. A further six months of intensive outpatient rehabilitation was provided with five hourly sessions per week including:supervised and self-managed hydrotherapy, plus one individual and two group falls' prevention sessions. These were supported by daily home exercises. At 12 mo post incident, recovery plateaued, then regressed following three falls. Rehabilitation was subsequently modified with the hydrotherapy retained and the group sessions replaced with an additional individual session supplemented with slacklining. The slacklining followed stages one and two of a standardized five-stage protocol. Self-reported functional progression resumed with improvement by 14 mo which further increased and was sustained 18 mo(Students' t test P < 0.05). Slacklining's external stimulations activate global-body responses through innate balance, optimal postural and potentially down-regulated reflex control. Incorporated into stroke rehabilitation programs, slacklining can provide measurable functional gains.

Control and Implementation of 2-DOF Lower Limb Exoskeleton Experiment Platform

In this study,a humanoid prototype of 2-DOF(degrees of freedom)lower limb exoskeleton is introduced to evaluate the wearable comfortable effect between person and exoskeleton.To improve the detection accuracy of the humanrobot interaction torque,a BPNN(backpropagation neural networks)is proposed to estimate this interaction force and to compensate for the measurement error of the 3D-force/torque sensor.Meanwhile,the backstepping controller is designed to realize the exoskeleton's passive position control,which means that the person passively adapts to the exoskeleton.On the other hand,a variable admittance controller is used to implement the exoskeleton's active followup control,which means that the person's motion is motivated by his/her intention and the exoskeleton control tries best to improve the human-robot wearable comfortable performance.To improve the wearable comfortable effect,serval regular gait tasks with different admittance parameters and step frequencies are statistically performed to obtain the optimal admittance control parameters.Finally,the BPNN compensation algorithm and two controllers are verified by the experimental exoskeleton prototype with human-robot cooperative motion.

Auditory P300 as an Indicator in Effectiveness of Robot-Assisted Lower Limb Rehabilitation Training among Hemiplegic Patients after Ischemic Stroke

Background: Robot-assisted lower limb rehabilitation training in early stage could improve the limb function among hemiplegic patients caused by ischemic stroke. P300 potential changes have importantly clinical value for evaluating the improvement in nerve function during the training as one of the objective targets. Methods: Sixty hemiplegic patients after stroke were randomly divided into a Lokomat group (30 cases) and a control group (30 cases). The Lokomat group received Lokomat rehabilitation while the control group only received traditional rehabilitation. The gait parameters and the balance ability were evaluated by the K421GAITRite analysis system and the Berg Balance Scale (BBS);ERP components including N100, N200, P200 and P300 potential were evaluated by a muscle electric inducing potentiometer. Results: There were no significant differences in BBS and gait parameters (P > 0.05), as well as in amplitude and incubation periods (IP) (P > 0.05) between the two groups before training. After 8 weeks treatment, the total (48.88 ± 3.68), static (26.40 ± 3.14) and dynamic (22.64 ± 3.68) balance scores improved significantly;the pace (59.22 ± 4.67), stride length (19.04 ± 2.24), feet wide (98.02 ± 7.97) and walking velocity (84.86 ± 9.88) and IP of N200 and P300 shortened obviously and P300 amplitude increased significantly in robot group (P < 0.05). Conclusion: This demonstrated that robot-assisted lower limb rehabilitation training in early stage could improve the limb function among hemiplegic patients caused by ischemic stroke. P300 may be considered as an indicator of neurological function improvement and effective robot-assisted lower limb rehabilitation training.