Configuration and Kinematics of a 3-DOF Generalized Spherical Parallel Mechanism for Ankle Rehabilitation

The kinematic equivalent model of an existing ankle-rehabilitation robot is inconsistent with the anatomical structure of the human ankle,which influences the rehabilitation effect.Therefore,this study equates the human ankle to the UR model and proposes a novel three degrees of freedom(3-DOF)generalized spherical parallel mechanism for ankle rehabilitation.The parallel mechanism has two spherical centers corresponding to the rotation centers of tibiotalar and subtalar joints.Using screw theory,the mobility of the parallel mechanism,which meets the requirements of the human ankle,is analyzed.The inverse kinematics are presented,and singularities are identified based on the Jacobian matrix.The workspaces of the parallel mechanism are obtained through the search method and compared with the motion range of the human ankle,which shows that the parallel mechanism can meet the motion demand of ankle rehabilitation.Additionally,based on the motion-force transmissibility,the performance atlases are plotted in the parameter optimal design space,and the optimum parameter is obtained according to the demands of practical applications.The results show that the parallel mechanism can meet the motion requirements of ankle rehabilitation and has excellent kinematic performance in its rehabilitation range,which provides a theoretical basis for the prototype design and experimental verification.

Type Synthesis of Self-Alignment Parallel Ankle Rehabilitation Robot with Suitable Passive Degrees of Freedom

The current parallel ankle rehabilitation robot(ARR)suffers from the problem of difficult real-time alignment of the human-robot joint center of rotation,which may lead to secondary injuries to the patient.This study investigates type synthesis of a parallel self-alignment ankle rehabilitation robot(PSAARR)based on the kinematic characteristics of ankle joint rotation center drift from the perspective of introducing"suitable passive degrees of freedom(DOF)"with a suitable number and form.First,the self-alignment principle of parallel ARR was proposed by deriving conditions for transforming a human-robot closed chain(HRCC)formed by an ARR and human body into a kinematic suitable constrained system and introducing conditions of"decoupled"and"less limb".Second,the relationship between the self-alignment principle and actuation wrenches(twists)of PSAARR was analyzed with the velocity Jacobian matrix as a"bridge".Subsequently,the type synthesis conditions of PSAARR were proposed.Third,a PSAARR synthesis method was proposed based on the screw theory and type of PSAARR synthesis conducted.Finally,an HRCC kinematic model was established to verify the self-alignment capability of the PSAARR.In this study,93 types of PSAARR limb structures were synthesized and the self-alignment capability of a human-robot joint axis was verified through kinematic analysis,which provides a theoretical basis for the design of such an ARR.

Configuration Design and Kinematic Performance Analysis of a Novel 4-DOF Parallel Ankle Rehabilitation Mechanism with Two Virtual Motion Centers

Aiming at the problem that the existing ankle rehabilitation robot is difficult to fully fit the complex motion of human ankle joint and has poor human-machine motion compatibility,an equivalent series mechanism model that is highly matched with the actual bone structure of the human ankle joint is proposed and mapped into a parallel rehabilita-tion mechanism.The parallel rehabilitation mechanism has two virtual motion centers(VMCs),which can simulate the complex motion of the ankle joint,adapt to the individual differences of various patients,and can meet the reha-bilitation needs of both left and right feet of patients.Firstly,based on the motion properties and physiological structure of the human ankle joint,the mapping relationship between the rehabilitation mechanism and ankle joint is determined,and the series equivalent model of the ankle joint is established.According to the kinematic and con-straint properties of the ankle equivalent model,the configuration design of the parallel ankle rehabilitation robot is carried out.Secondly,according to the intersecting motion planes theory,the full-cycle mobility of the mechanism is proved,and the continuous axis of the mechanism is judged based on the constraint power and its derivative.Then,the kinematics of the parallel ankle rehabilitation robot is analyzed.Finally,based on the OpenSim biomechanical soft-ware,a human-machine coupling rehabilitation simulation model is established to evaluate the rehabilitation effect,which lays the foundation for the formulation of a rehabilitation strategy for the later prototype.

The Human Ankle-Foot Complex as a Multi-Configurable Mechanism during the Stance Phase of Walking

The objective of this study is to investigate the biomechanical functions of the human ankle-toot complex during the stancephase of walking. The three-dimensional (3D) gait measurement was conducted by using a 3D infrared multi-camera system anda force plate array to record the Ground Reaction Forces (GRF) and segmental motions simultaneously. The ankle-foot complexwas modelled as a four-segment system, connected by three joints: talocrural joint, sub-talar joint and metatarsophalangeal joint.The subject-specific joint orientations and locations were determined using a functional joint method based on the particleswarm optimisation algorithm. The GRF moment arms and joint moments acting around the talocrural and sub-talar joints werecalculated over the entire stance phase. The estimated talocrural and sub-talar joint locations show noticeable obliquity. Thekinematic and kinetic results strongly suggest that the human ankle-foot complex works as a mechanical mechanism with twodifferent configurations in stance phase of walking. These lead to a significant decrease in the GRF moment arms therebyincreasing the effective mechanical advantages of the ankle plantarflexor muscles. This reconfigurable mechanism enhancesmuscle effectiveness during locomotion by modulating the gear ratio of the ankle plantarflexor muscles in stance. This studyalso reveals many factors may contribute to the locomotor function of the human ankle-foot complex, which include not only itsre-configurable structure, but also its obliquely arranged joints, the characteristic heel-to-toe Centre of Pressure (COP) motionand also the medially acting GRF pattern. Although the human ankle-foot structure is immensely complex, it seems that itsconfiguration and each constitutive component are well tuned to maximise locomotor efficiency and also to minimise risk ofinjury. This result would advance our understanding of the locomotor function of the ankle-foot complex, and also the intrinsicdesign of the ankle-foot musculoskeletal structure. Moreover, this may also provide implications for the design of bionicprosthetic devices and the development of humanoid robots.

The effects of total ankle replacement on ankle joint mechanics during walking

Background:End-stage ankle arthritis impairs joint function and patients' mobility.Total ankle replacement is a surgical procedure to treat severe ankle arthritis.Salto Talaris Anatomic Ankle^(TM)(STAA) was designed to mimic the normal ankle anatomy and flexion/extension of the ankle movement.The purpose of this study was to examine the effect of an STAA ankle replacement on ankle joint function and mechanics during gait.Methods:Five patients with end-stage unilateral ankle arthritis were recruited.Patients performed level walking in a laboratory setting on 2occasions,prior to and 3 months after the STAA ankle surgeries.American Orthopedic Foot and Ankle Society(AOFAS) hindfoot score was obtained.A 12-camera motion capture system was used to perform walking analysis.Gait temporo-spatial parameters and ankle joint mechanics were evaluated.Paired Student's t tests and non-parametric Wilcoxon matched tests were performed to examine the differences in biomechanical variables between the pre-and post-surgery walking conditions.Results:Compared to the pre-surgical condition,at 3 months of post-STAA surgery,patients experienced greater improvement in AOFAS hindfoot score(p = 0.0001);the STAA ankle demonstrated a 31% increase in ankle joint excursion(p = 0.045),a 22% increase in ankle plantarflexor moment(p = 0.075),a 60% increase in ankle power absorption(p = 0.023),and a 68% increase in ankle power production(p = 0.039).Patients also demonstrated a 26% increase in walking speed(p = 0.005),a 20% increase in stride length(p = 0.013),a 15% decrease in double support time(p = 0.043),and a 5% decrease in total stance time(p = 0.055).Conclusion:Three months after surgeries,the STAA patients experienced improvements in ankle function and gait parameters.The STAA ankle demonstrated improved ankle mechanics during daily activities such as walking.

Radiographic assessment of leg alignment and grading of knee osteoarthritis:A critical review

Knee osteoarthritis(OA) is a progressive joint disease hallmarked by cartilage and bone breakdown and associated with changes to all of the tissues in the joint,ultimately causing pain,stiffness,deformity and disability in many people.Radiographs are commonly used for the clinical assessment of knee OA incidence and progression,and to assess for risk factors.One risk factor for the incidence and progression of knee OA is malalignment of the lower extremities(LE).The hipknee-ankle(HKA) angle,assessed from a full-length LE radiograph,is ideally used to assess LE alignment.Careful attention to LE positioning is necessary to obtain the most accurate measurement of the HKA angle.Since full-length LE radiographs are not always available,the femoral shaft-tibial shaft(FS-TS) angle may be calculated from a knee radiograph instead.However,the FS-TS angle is more variable than the HKA angle and it should be used with caution.Knee radiographs are used to assess the severity of knee OA and its progression.There are three types of ordinal grading scales for knee OA:global,composite and individual feature scales.Each grade on a global scale describes one or more features of knee OA.The entire description must be met for a specific grade to be assigned.The KellgrenLawrence scale is the most commonly-used global scale.Composite scales grade several features of knee OA individually and sum the grades to create a total score.One example is the compartmental grading scale for knee OA.Composite scales can respond to change in a variety of presentations of knee OA.Individual feature scales assess one or more OA features individually and do not calculate a total score.They are most often used to monitor change in one OA feature,commonly joint space narrowing.The most commonly-used individual feature scale is the OA Research Society International atlas.Each type of scale has its advantages;however,composite scales may offer greater content validity.Responsiveness to change is unknown for most scales and deserves further evaluation.

A Development of Rom-Exercise Machine Using Linkages(Design of Leg Mechanism by Walking Simulation)

In this study, the design of an automatic ROM-Exercise machine that is constructed witha planar multililnk mechamsm consisting of only revolute pairs is investigated. Namely, equations thatdetermine the minimum moving spaces and relative positions of link required to construct the legmechanism are formulated with consideration of transform functions. For the leg mechanism that isconstructed with a planar eleven-link mechanism, arrangements of each link and optimum linkprofiles avoided mutual interferences among moving links are determined wb consideration of therelative locations of each link in the same plane during a cycle of motion of the mechanism. Based onthe above analytical results, an automatic ROM-Exercise machine that performs within a minimum moving spaces is proposed as a prachcal example. ms study is carried out as part of the students'computcr education to the graduation thesis, in order to improve their creativity and machine designtechnology skills in coniunction with educational advantages. Significam educational results areobtained by using the design techniques mentioned above.

提篮式拱梁组合体系桥梁拱梁结合段受力特性研究

为了解提篮式拱梁组合体系桥梁拱梁结合段的受力特性,以福州至长乐机场城际铁路乌龙江大桥为背景,建立该桥拱梁结合段精细化有限元模型,考虑几何大变形、材料非线性等效应进行全过程非线性分析,得到不同荷载阶段下拱梁结合段的应力分布,研究拱梁结合段的破坏模式和受力特性。结果表明:随着荷载增加,中拱拱脚外侧加劲肋与底板交界处最先屈服,最不利截面位于拱肋壁板与拱脚横隔板交界处;拱梁结合段的弹性承载力系数为2.32,塑性承载力系数为4.71。当荷载达3.57倍最不利荷载组合时,最不利截面拱肋壁板与拱脚横隔板相交的角点先达到屈服;当荷载达4.25倍最不利荷载组合时,1/2最不利截面屈服,屈服区域由角点屈服向拱肋上部区域扩展;当荷载达4.71倍最不利荷载组合时,最不利截面大部分屈服,拱肋壁板屈服区域向整个截面扩展,拱肋因屈服区域过大而丧失承载力。拱肋壁板屈服区域扩展过程中,内、外侧加劲肋逐步屈服;设置外侧加劲肋有利于推迟拱肋壁板的屈服。

基于三点力原理对足内翻矫形器矫正效果的有限元分析

背景:三点力学是踝足矫形器矫正与预防足部各类疾病的有效方法,目前关于3D打印踝足矫形器的临床应用研究已普遍存在,但其涉及三点力学矫正的数值模拟与有限元分析报道相对较少,缺乏相关生物力学实验验证。目的:通过有限元法对踝足矫形器与足部复合模型进行三点力加载分析,观察在三点力干预下佩戴踝足矫形器的足部矫正效果,验证三点力的有效性及踝足矫形器的可靠性。方法:基于医学图像处理软件Mimics构建1例健康志愿者足踝三维模型,采用Rodin 4D与Geomagic逆向工程软件对各模型进行优化处理,设计个性化踝足矫形器模型。利用Solidworks软件对足踝模型进行内侧翻转10°以模拟足内翻病态,通过ANSYS软件结合三点力学原理对足部施力区进行静力加载,在满足人体足部痛阈时分析足踝各组织形变与应力变化,利用显示动力学进一步验证踝足矫形器施加三点力的有效性。结果与结论:(1)设计的个性化踝足矫形器具有预防足踝内翻和固定作用,在未穿戴踝足矫形器时,受到1 N·m内翻载荷后足踝内翻1.81mm,而穿戴踝足矫形器后仅为0.44mm,变形率降低75.7%,预防内翻效果明显增强;(2)仅冠状面矫正时,跟骨力系过小会加剧患者前足内翻,调整足跟内侧与内踝上方矫正力后,前足内翻角与跟骨位得到改善,但足部内侧趾骨区仍有不同程度内收移位,会加剧患者前足内收畸形;(3)冠状面、水平面两组三点力系统联合作用矫正效果优于单冠状面,表现为在足跟内侧、第一跖骨干内侧、外踝下方与内踝上方的力(25,10,10,20 N)作用下,前足内侧趾骨无内收移位,前足内翻角减小,并沿X轴外翻矫正1.395 mm,跟骨外翻矫正1.227mm,在变形比例放大云图下跟骨内翻角由10.21°矫正至7.25°,内翻角改善28.9%;(4)两平面三点力作用下,足底外侧跖骨负荷减小,内侧跖骨负荷增加,矫正后足底骨骼应力显著得到改善,进一步验证了三点力原理的可靠性,该研究为临床患者穿戴踝足矫形器治疗足内翻提供了重要理论支撑。

Design of a Flexible Bionic Ankle Prosthesis Based on Subject-specific Modeling of the Human Musculoskeletal System

A variety of prosthetic ankles have been successfully developed to reproduce the locomotor ability for lower limb amputees in daily lives. However, they have not been shown to sufficiently improve the natural gait mechanics commonly observed in comparison to the able-bodied, perhaps due to over-simplified designs of functional musculoskeletal structures in prostheses. In this study, a flexible bionic ankle prosthesis with joints covered by soft material inclusions is developed on the basis of the human musculoskeletal system. First, the healthy side ankle–foot bones of a below-knee amputee were reconstructed by CT imaging. Three types of polyurethane rubber material configurations were then designed to mimic the soft tissues around the human ankle, providing stability and flexibility. Finite element simulations were conducted to determine the proper design of the rubber materials, evaluate the ankle stiffness under different external conditions, and calculate the rotation axes of the ankle during walking. The results showed that the bionic ankle had variable stiffness properties and could adapt to various road surfaces. It also had rotation axes similar to that of the human ankle, thus restoring the function of the talocrural and subtalar joints. The inclination and deviation angles of the talocrural axis, 86.2° and 75.1°, respectively, as well as the angles of the subtalar axis, 40.1° and 29.9°, were consistent with the literature. Finally, dynamic characteristics were investigated by gait measurements on the same subject, and the flexible bionic ankle prosthesis demonstrated natural gait mechanics during walking in terms of ankle angles and moments.

运动干预慢性踝关节不稳研究进展

该文以运动和慢性踝关节不稳(Chronic Ankle Instability,CAI)等关键词在中国知网以及Pubmed数据库进行文献检索以及梳理,探讨运动干预慢性踝关节不稳的研究内容。慢性踝关节不稳的风险因素主要是平衡受损、腓骨肌反应时间延长、力量缺陷以及本体感觉受损。研究结果发现,运动疗法以力量训练、平衡训练、神经肌肉训练和本体感觉训练为主,运动改善CAI的机制可能是通过改善神经肌肉控制能力来改善CAI。

Rare pattern of Maisonneuve fracture:A case report

BACKGROUND Maisonneuve fracture is a special type of ankle fracture that consists of proximal fibular fracture,a lesion of the inferior tibiofibular syndesmotic complex(interosseous ligament,anterior inferior tibiofibular ligament and posterior inferior tibiofibular ligament),and injury of the medial structure of the ankle(deltoid ligament tear or medial malleolar fracture).The accepted mechanism of Maisonneuve fracture is pronation external rotation according to the Lauge-Hansen classification.In this paper,we report a rare pattern of Maisonneuve fracture,which has the characteristics of both pronation external rotation ankle fracture and supination adduction ankle fracture.CASE SUMMARY A 31-year-old female patient accidentally sprained her right ankle while walking 5 d before hospitalization in our hospital.The patient was initially missed in other hospitals and later rediagnosed in our outpatient department.Full-length radiographs of the lower leg revealed proximal fibula fracture,inferior tibiofibular joint separation,and medial malleolar fracture involving the posterior malleolus,which was also revealed on computed tomography scans.Magnetic resonance imaging revealed rupture of the anterior inferior tibiofibular ligament and anterior talofibular ligament.We diagnosed a rare pattern of Maisonneuve fracture with proximal fibular fracture,inferior tibiofibular joint separation,medial malleolar fracture and ruptures of the anterior inferior tibiofibular ligament and anterior talofibular ligament.The patient underwent open reduction and internal fixation in our hospital.A 6-mo postoperative follow-up confirmed a good clinical outcome.CONCLUSION To our knowledge,this rare pattern of Maisonneuve fracture has not been previously described.The possible mechanism of injury is supination adduction combined with pronation external rotation.Careful analysis of the injury mechanism of Maisonneuve fracture is of great clinical significance and can better guide clinical treatment.

一种带块式指节限位机构模块化机械手的研究

为了解决现有欠驱动模块化机械手指节限位机构结构复杂、更换手指不方便及功能单一的问题,基于欠驱动原理设计了一种采用块式指节限位机构的模块化机械手。块式指节限位机构结构简单,模块化手指更换方便,可以实现多功能抓取和捏取。采用机构静力学分析方法,对机械手捏取状态下的手指进行了静力学分析,推导出了末端指节的接触力计算公式。采用ADAMS软件对机械手进行了接触力分析,仿真结果表明,模块化机械手可稳定包络抓取直径为80~150 mm的3种球状物体,接触力控制在5.86~13.91 N,可包络抓取直径为60~100 mm的3种圆柱状物体,接触力控制在9.16~18.69 N,可捏取厚度为0~12 mm的2种薄片状物体,接触力可以达到任意设定值。研究设计的机械手通用性强,适用范围广,为机械手的研发提供了参考。

摇拔戳手法治疗急性外侧踝关节扭伤后距腓前韧带力学分析

目的探究摇拔戳手法治疗急性外踝关节扭伤的力学作用机理。方法在中国中医科学院望京医院急诊科收集1例外踝关节扭伤患者,扫描并保存患者胫骨远端1/3以下踝关节CT断层图片,利用Abaqus 6.13和Mimics10.0软件来构建足踝三维有限元模型。记录手法治疗前、初次治疗后、疗程结束2周3个时间点的在体力学数据,经过数据转换处理后代入有限元模型中,分析在3个不同时间点4种工况下距腓前韧带的参数及力学数据。结果有限元加载试验提示,随着时间进展,经手法治疗后,距腓前韧带的弹性模量逐渐降低,距腓前韧带的最大应力逐渐增大。结论摇拔戳手法能通过降低距腓前韧带的弹性模量,使距腓前韧带承受的最大应力增加。可能是通过手法缓解踝关节扭伤后踝周围韧带的痉挛紧张状态,提高韧带对力的耐受,这可能是摇拔戳手法治疗外侧踝关节扭伤的力学作用机制之一。

机械动力牵拉法结合递进式目标康复锻炼对旋前外旋型踝关节骨折术后功能恢复的影响

目的 探讨机械动力牵拉法结合递进式目标康复锻炼对旋前外旋型(PER)踝关节骨折术后患者功能恢复效果的影响。方法 选取2017年2月—2021年2月南京大学医学院附属鼓楼医院收治的94例PERⅢ度或Ⅳ度踝关节骨折患者为观察对象,根据术后康复锻炼的方式不同分为观察组(44例)和对照组(50例)。对照组术后予以递进式目标康复锻炼,观察组在对照组基础上联合机械动力牵拉。比较两组VAS评分、踝关节背伸与跖屈角度、踝关节肿胀、AOFAS踝-后足评分、生活质量评分及并发症发生率的差异。结果 观察组患者术后3、6月VAS疼痛评分显著低于对照组(均P<0.05)。观察组患者术后2周、1月、3月、6月踝关节背伸与跖屈角度显著高于对照组(均P<0.05)。两组患者术前、术后2周、1月、3月、6月踝关节骨折患者踝关节肿胀度比较,差异均无统计学意义(均P>0.05)。观察组患者AOFAS踝-后足评分优良率高于对照组(90.9%vs 70.0%,χ^(2)=6.345,P=0.012)。观察组AOFAS踝-后足评分中异常步态、前后活动(屈/伸)评分明显高于对照组(均P<0.05)。观察组患者术后6个月的物质、心理、社会、躯体等生活质量的各维度评分明显高于对照组(均P<0.05)。两组患者并发症发生率比较差异无统计学意义(P>0.05)。结论 机械动力牵拉法结合递进式目标康复锻炼应用于PERⅢ度或Ⅳ度踝关节骨折术后患者可减轻疼痛程度,改善踝关节功能。

面向踝关节康复混联R&(2-SPU+PRR)机构的设计及运动学分析

针对脑卒中患者的踝关节康复及训练,提出一种具有3R1T运动性能的脚踝康复机构。运用螺旋理论分析自由度,利用封闭矢量法求解位置逆解,运用Adams对混联机构进行了运动学分析;并计算了该机构在背伸、趾屈运动时最大转动角度误差值。结果表明,在限位装置的限制下,该机构可在踝关节安全运动范围之内完成患者所需康复运动及竖直方向的关节牵引运动。

踝关节康复机构的结构设计与训练规划

为了保证踝关节康复训练的效果和安全性,设计了一种基于3-UPRU/S并联构型的踝关节康复机构及其脚部固定与快放组件,并对其运动性能与训练规划进行了研究。考虑到踝关节生理回转中心与机构转动中心不重合的影响,应用Adams软件建立了康复机构的脚踝虚拟模型,并利用角速度规划的方法对S型与T型角速度曲线进行优化,得到了一种更优的训练规划;通过逆运动学仿真,得到机构各促动器的位移数据,并使用样条拟合确定了各促动器的驱动函数;通过原理样机试验,进行了实际工作角度与训练规划的验证。结果表明,优化后该康复机构1个周期内增加了约12%的匀速训练时间,并减少了约47%的角速度波动;该训练规划能够提高踝关节康复的效果以及安全性。

混联式踝关节康复机构设计与输出受限控制研究

踝关节损伤是人体损伤常见形式,踝关节康复治疗受到越来越多的关注与研究。混联机构用于踝关节损伤后康复运动中,可有效提高康复机械装置康复效果。在对人体踝关节的结构特征和运动形式解析的基础上,提出一种4自由度的(2-UPU-PU)&R混联式康复机构。利用修正的K-G公式分析脚踝康复机构的自由度,基于闭环矢量法求解了机构的位置逆解,采用搜索法求解机构的工作空间,设计位置及速度输出受限控制系统,验证所设计机构能满足康复需求,保障使用安全性,为后续控制系统设计提供理论指导。

基于fMRI对视觉反馈平衡仪联合腕踝针治疗脑卒中后平衡障碍的机制

目的观察视觉反馈平衡仪联合腕踝针治疗脑卒中后平衡障碍的临床疗效及功能磁共振成像(fMRI)变化。方法采用随机数字表法将康复科住院的90例脑卒中后平衡障碍患者分为对照组、平衡组和联合组,各30例。所有患者均接受常规脑卒中康复训练,平衡组在此基础上增加视觉反馈平衡训练仪,联合组在平衡组的基础上增加踝关节的围刺法治疗。分别在治疗前、治疗后2周和4周时测定3组患者平衡指标并进行静息态血氧水平依赖性功能磁共振成像(BOLD-fMRI)和弥散张量成像(DTI)的检查,比较3组患者平衡参数、各脑区[感觉运动区(SMC区)、辅助运动区(SMA区)、主运动区(M1区)、小脑]的比率低频振幅(fALFF)和皮质脊髓束的各向异性分数(FA)值。结果治疗后2周和4周时,3组患者轨迹长、左右偏离、外周面积和矩形面积等重心转移轨迹参数,X轴重心转移距离均值(Mean-X)、Y轴重心转移距离均值(Mean-Y)、X轴重心转移距离最大值(Max-X)、Y轴重心转移距离最大值(Max-Y)、重心转移距离(LSKG)、重心转移面积(SSKG)、重心转移面积比(LFS)等重心转移距离参数以及体质量分布系数(WDI)和稳定性系数(SI)均显著降低,单位面积轨迹长均显著增加(P<0.05)。联合组患者治疗后2周和4周时的轨迹长、左右偏离、外周面积和矩形面积等重心轨迹参数,Mean-X、Mean-Y、Max-X、Max-Y、LSKG、SSKG、LFS等重心转移距离参数以及WDI和SI均显著小于对照组和平衡组,单位面积轨迹长显著大于对照组和平衡组(P<0.05)。经过治疗,3组患者SMC区、M1区、SMA区和小脑等fALFF以及患侧皮质脊髓束FA均呈显著增加趋势(P<0.05)。联合组患者治疗后2周和4周时SMC区、M1区、SMA区和小脑等fALFF以及患侧皮质脊髓束FA均显著大于对照组和平衡组,平衡组显著大于对照组,差异有统计学意义(P<0.05)。结论视觉反馈平衡仪联合腕踝针能够有效改善脑卒中后平衡障碍患者平衡功能,这与脑卒中后神经可塑和运动功能重组有关,可将fALFF和FA作为平衡障碍康复指标使用。

3R1T型并联式踝关节康复机构型综合

针对踝关节的活动度和康复训练的条件进行分析,确定期望自由度的类型,明确构型综合的目标为3R1T型,通过约束螺旋综合法进行构型综合。首先求解3R1T型并联机构的运动螺旋系与约束螺旋系,推导出3R1T型并联机构不同自由度分支的约束螺旋系与运动螺旋系。然后通过对分支的运动螺旋系进行线性变换得到不同结构的串联分支,将分支组合得到一系列不同类型的3R1T型并联机构。最后选取其中一种构型进行瞬时机构的判别,为康复机构的本体设计提供理论依据。