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.

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.

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.

Finite element modeling and injury criteria investigation for the lower leg of the Chinese human body under impact loads

The widely used human body injury criteria were established based on the biomechanical response of the EuroAmerican human body,without considering the differences in anthropometry and injury characteristics among different races,particularly the Chinese human body which typically has the smaller body size.The absence of such race specific design considerations negatively influences the injury prevention capability for these populations,and weakens the applicability of injury criteria.To resolve these issues,this study aims to develop a lower leg finite element model of a 50th percentile Chinese male.The model is built based on the medical images of an average size Chinese male with detailed ankle ligaments and lower leg muscles modeled.Data from sixty experiments available in the literature are used to validate its biofidelity.Using the validated model,the lower leg model is subjected to combined axial compression and bending loads to evaluate its injury criteria.Compared with a typical Euro-American human body mode,the Chinese lower leg presents reduced mechanical tolerance,and the revised tibia index may be an appropriate injury criteria for the Chinese lower leg.Additionally,the validated model reproduces the pedestrian lower leg fracture in a domestic accident.

Simple bone cysts of the proximal humerus presented with limb length discrepancy:A case report

BACKGROUND Simple bone cysts(SBC)are benign tumor-like bone lesions typically identified in children.While SBC may lead to growth disturbances or growth arrest,such cases are uncommon.The mechanisms behind these observations remain unclear.Additionally,research on the etiology of SBC remains inconclusive,and there has been no consensus on the appropriate timing and methodology for treatment.CASE SUMMARY Here,we present our experience in the successful surgical management of a 10-year-old girl with SBC,who presented with a pathological fracture complicated by malunion of the displaced fracture,varus deformity,and limb length discrepancy.We hypothesized two possible etiologies for the patient’s growth arrest and subsequent humerus varus deformity:(1)Direct disruption of the physis by fluid from the cyst itself;and(2)damage to the epiphysis due to repetitive pathological fractures associated with SBC.In addressing this case,surgical intervention was undertaken to correct the proximal humerus varus deformity.This approach offered the advantages of simultaneously correcting angular abnormalities,achieving mild limb lengthening,providing definitive SBC treatment,and reducing the overall treatment duration.CONCLUSION As per current literature,acute correction of acute angular deformity in proximal humeral SBC is not well comprehended.However,in this specific case,acute correction was considered an optimal solution.

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.

The design of exoskeleton lower limbs rehabilitation robot

To achieve human lower limbs rehabilitation training, the exoskeleton lower limbs rehabilitation robot is designed. Through respective motor driving, the retarding mechanism and telescopic adjusting mechanism, the function of human walking is accomplished. After the design of the mechanical structure, the finite element analysis is carried out on the important parts and the control system is achieved by Single Chip Microcomputer.

Training and Recommendations on the Lower Limbs Explosive Force of Juvenile Amateur Men Sprinters

Based on the characteristics of physiological development of China's juvenile men sprinters,combined with the training mechanism of explosive force,and taking the track- and- field team of Jianshan High School in Chongqing as experimental object,this article selects the combination of one leg training methods and the combination of two legs training methods to carry out group control experiment. The result shows: each index score of the two groups of athletes is improved after training,but the characteristics of employing forces and the way of muscle work in one leg jumping exercises such as the one leg jump and step are much closer to sprint techniques. And using this kind of methods can effectively develop the special quality of juvenile sprinter.

Effects of Hip Arthroplasties on Bone Adaptation in Lower Limbs: A Computational Study

Gait disorders contribute to the risk of falls and successive injuries, especially to elderly populations. The risk of falls becomes higher for hip osteoarthritis (OA) and hip arthroplasties patients due to poor balancing and gait impairment. Bone adaptation and bone loss are fundamental issues in considering the changes of bone behavior and gait pattern. In this study, computational analysis of the lower limbs was conducted to estimate the bone adaptation after hip arthroplasties procedure. 3D inhomogeneous model of lower limb was developed from computed topography (CT- based) data of 79 years old patient with hip osteoarthritis problem in left limb. Two types of arthroplaties were constructed in the left limb, namely total hip arthroplasty and resurfacing hip arthroplasty using commercial biomedical software, Mechanical Finder v6.1. Prosthesis stem and acetabular cup of THA were modelled as titanium alloy material (E = 114 GPa, v = 0.34), femoral ball and bearing insert as alumina properties (E = 370 GPa, v = 0.22). Meanwhile, RHA implant was assigned as Co-Cr-Mo material (E = 230 GPa, v = 0.30). Contact between both implants and bone were considered to be perfectly bonded at the interface. A load case of quiet standing position was conducted in this analysis with 60 kg of the patients’ body weight. The load was applied at the cross sectional lumbar vertebra and fixed at the distal of femoral shafts. Results show different patterns of stress distribution in right and left (operated) limbs for hip OA, THA and RHA models. An indication of stress alteration on both limbs after arthroplasties suggested that the bone adaptation occurred. The higher percentage of change in the left limb projected that the adaptation was more critical in operated limb.

Experimental Study on Seismic Behavior of Exterior Joints of Special-shaped Columns with Different Lengths of Limbs

Four exterior joints with special-shaped columns which have different lengths of limbs are tested under low cyclic loading. Speeial-shaped columns adopted are L- and T-shaped in section. It can be concluded that crack pattern, failure mode and shear strength of joints are affected by the length of limb, and that shear strength and ductility increase with the length of limb; the joints with the flexural failure of the beam have better seismic behavior than those with the shear failure of the joint core.

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.

Epidemiological and Clinical Pattern of Open Fractures of Long Bones of the Lower Limbs in the South-West Region of Cameroon: A 5-Year Review

Background: An open fracture is an injury in which the fracture site and/or hematoma communicates with the external environment. It is associated with significant morbidity and disability and is a challenge to the surgical team. The lower extremities are the most often exposed to traumatic injuries compared to other anatomical parts of the body. Patterns of open fractures differ with different mechanisms of injury and the segment of the long bone affected. The correct and timely management of open fractures is beneficial to the patients and leads to a more favorable outcome. This study aimed at describing the pattern of open fractures of long bones of the lower limb treated in 3 major hospitals of the south west region, Cameroon. Methodology: This was a hospital-based retrospective review of files of patients with open fractures of long bones of the lower limb managed at the surgical units of three secondary health facilities in the South-West region of Cameroon from the 1st of January 2015 to the 31st of December 2019. The socio-demographic characteristics, clinical presentation, treatment modalities, and outcomes were recorded. The data was stored and analyzed using Epi info version 7.0 and SPSS version 23.0 respectively. Results: A total of 195 files of patients aged 8 to 80 years were studied. The main age group affected was between 20 - 40 years. There were 147 (75.4%) males and 48 (24.6%) females giving a sex-ratio of 3.1:1. The most common cause was road traffic crashes 142 (72.8%). In 98 cases (50.3%), the left side was more involved. The tibia was the most common long bone affected in 75 (38.5%) cases. Comminuted fracture was the most common fracture pattern encountered in 126 cases (64.6%). A total of 76 (39%) fractures were graded Gustilo-Anderson IIIA. External fixator was used in 112 cases (57.1%) and internal fixator in 86 cases (42.9%). We recorded 127 (65.1%) cases of wound infection and 143 (73.3%) cases of limb shortening as the most common complications. Other complications include: 20 cases (17.1%) of mal-union, 27 cases (22.5%) of delayed union, 18 cases (15.1%) of non-union and 50 cases (38.5%) chronic osteomyelitis. We recorded a mortality of 2.1%. Gustilo IIIB and IIIC were associated to chronic osteomyelitis (P = 0.02). Conclusion: Open fractures of long bones of the lower limb affect the active age group of the population and road traffic crashes are the most common causes. It tends to affect the left side and the tibia being the most fractured long bone. A reasonable proportion of these fractures subsequently get infected. Comminuted fracture is the common fracture pattern.

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.

Association between serum retinol-binding protein and lower limb atherosclerosis risk in type 2 diabetes mellitus

BACKGROUND Serum retinol-binding protein(RBP)is the primary transport protein of circulating vitamin A.RBP has a crucial role in maintaining nutrient metabolism and physiologic homeostasis.Several studies have indicated that serum RBP participates in the progression of diabetes and diabetes-related complications.However,the impact of serum RBP on lower limb atherosclerosis has not been determined in individuals with type 2 diabetes mellitus(T2DM).AIM To determine the association between serum RBP and lower limb atherosclerosis in individuals with T2DM.METHODS This retrospective study enrolled 4428 eligible T2DM patients and divided the patients into non-lower limb atherosclerosis(n=1913)and lower limb atherosclerosis groups(n=2515)based on lower limb arterial ultrasonography results.At hospital admission,baseline serum RBP levels were assessed,and all subjects were categorized into three groups(Q1-Q3)based on RBP tertiles.Logistic regression,restricted cubic spline regression,subgroup analysis,and machine learning were used to assess the association between RBP levels and lower limb atherosclerosis risk.RESULTS Among 4428 individuals with T2DM,2515(56.80%)had lower limb atherosclerosis.Logistic analysis showed that lower limb atherosclerosis risk increased by 1%for every 1 unit rise in serum RBP level(odds ratio=1.01,95%confidence interval:1.00-1.02,P=0.004).Patients in the highest tertile group(Q3)had a higher lower limb atherosclerosis risk compared to the lowest tertile group(Q1)(odds ratio=1.36,95%confidence interval:1.12-1.67,P=0.002).The lower limb atherosclerosis risk gradually increased with an increase in RBP tertile(P for trend=0.005).Restricted cubic spline analysis indicated a linear correlation between serum RBP levels and lower limb atherosclerosis risk(non-linear P<0.05).Machine learning demonstrated the significance and diagnostic value of serum RBP in predicting lower limb atherosclerosis risk.CONCLUSION Elevated serum RBP levels correlate with an increased lower limb atherosclerosis risk in individuals with T2DM.

Prevention and Treatment of Deep Vein Thrombosis of the Lower Limbs in Patients with Complications after Orthopedic Trauma Surgery

Objective:To explore and analyze on how to prevent and treat deep vein thrombosis of the lower limbs in patients with complications after orthopedic trauma surgery.Methods:The research patients were selected from the cases of surgical treatment of orthopedic trauma in the hospital during the past two years,and a total of 58 patients were selected.The patients were randomly divided into two groups,with 29 patients in the control group treated with conventional clinical methods;and the other 29 patients were assigned to the experimental group,where targeted preventive and therapeutic measures were administered.During the research,the number of complications of postoperative deep vein thrombosis of the lower limbs and the corresponding treatment efficacy were compared between the two groups of patients.Results:According to the results of clinical experiments,the probability of patients in the experimental group suffering from deep vein thrombosis of the lower limbs after surgery was significantly lower than that of the control group(P<0.05);in addition,when complications of deep venous thrombosis of the lower limbs occurred,the treatment efficacy of the patients in the experimental group was 96.55%,and the treatment efficacy of the patients in the control group was 82.76%.There was a significant difference between the two groups(P<0.05).Conclusion:Through clinical experiments to study and analyze the prevention and treatment measures of deep vein thrombosis in patients with complications after orthopedic trauma surgery,this research proves that active and comprehensive preventive and treatment measures can effectively reduce the number of complications and improve surgery treatment efficacy.

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.

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.

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.