600 out of every 100,000 people in the United States today suffer from some form of cerebellar disease that causes major abnormalities in the equilibrium and aligned, coordinated movement of the body. Hence it becomes essential to diagnose the extent of the movement and gait disorder and provide required therapy to the patients. Various developments have been made in the designing and application of interactive software system for body positioning. Object oriented design techniques are used in the field of software engineering for interactive geometric representation of system behavior. Motion analysis of the upper and lower extremities of the body could be beneficial in the diagnosis and therapy of numerous orthopedic and neurological ailments. Mathematical models of neuro-musculoskeletal dynamics establish a scientific basis for movement analysis. As mentioned above, an interactive geometric representation of the system behavior is an important diagnostic tool in orthopedic therapy. This realistic depiction of the human body with respect to the model is a very effective diagnostic tool for clinicians. There are existing biomechanical modeling tools like Visual 3-D etc, that are used for motion analysis. Visual 3-D was developed by the movement disorders laboratory at NIH. The preferred method is to place markers on the segments and calculate the joint center locations using a rigid-body assumption. However studies have shown that markers on the joint centers are subject to artifact (skin movement). Moreover, very few details are provided on the algorithm used by Visual 3-D, and no "fixes" are provided for marker dropout. This project aims at testing the accuracy of existing biomechanical movement analysis software Visual 3D by calculating the rigid body motion from the spatial co-ordinates of the markers clusters on the subject's upper extremities. This project tries to emulate their approach in a simple and effective manner and at the same time validate the approach by testing it by three different methods by calculating the elbow and wrist locations during a forward reaching motion of the subject. A mathematical model is developed by determining a relationship between the projections of a particular point in two different planes or on a single plane in two different directions [Kinzel, G.L. et. al. 1972]. The computer simulations are performed using MATLAB to calculate the lunematical parameters from the co-ordinates of projections of markers placed on the upper extremities of the subject's body. This relation will aid in quantitative motion analysis of the upper extremities in the rehabilitation setting. This can be extended to in-depth gait analysis of the lower extremities too. This type of biomechanical movement analysis allows us to understand the dynamic implications of a particular impairment, such as spasticity or weakness, in a particular muscle group.

Thesis name: The evaluating of the change of walking quality in dancers in comparison with the normal population Thesis goal: This thesis deals with effect of long-term ballet dance on kinematic parameters of gait. The theoretical part includes basic characteristics of gait cycle and kinesiological and biomechanical findings of ballet movement and its compensatory mechanisms in musculoskeletal system. There is analyzed angular parameters of gait cycle in ballet dancers in performance of walking in the experimental part. The results will show if the many-years intensive training of dance affects the alignment of particular joints of the body during human walk. Method: Kinematic analysis by Qualisys system allowing automatic processing of record obtained with infrared cameras. Qualisys uses its own high-frequency cameras for precise movement tracking of the measured object using active or passive markers. Gathered data from device were processed and statictically evaluated with Microsoft Office Excel. Keywords: gait, bipedal locomotion, dance, gait analysis, gait of dancers, ballet, kinematics analysis

Title Gait Analysis in Adolescents with Idiopathic Scoliosis: A Systematic Review. Aim The role of spine is vital as a gait stabilizer. Gait analysis may provide a more holistic view of how the body behaves to idiopathic scoliosis among adolescents. The aim of this thesis is to review the effectiveness and validity of gait analysis in examining AIS, and secondly to assess how the gait of AIS patients differ from adolescents without scoliosis. Method A systematic review of the topic was conducted. Information was gathered from six e-databases, and seventeen articles were selected, of which seven focusing solely on AIS subjects (i.e. non-comparative) and ten were focusing on AIS in relation to control subjects (i.e. comparative). Results Spatio-temporal (STP), kinematic, kinetic and EMG parameters show significant changes in AIS subjects during walking. But variations between results, lack of data for certain parameters and no significant relationship between gait parameters and scoliosis was also seen. Furthermore, AIS subjects differ in performance compared to non-scoliosis adolescents in at least one gait parameter across all studies. This includes abnormalities in muscle activity, less economical use of the body, poorer performance in kinematic parameters and differences in STP such as step...

L’examen clinique et les radiographies standard des membres inférieurs et des pieds comportent des biais liés à la reproductibilité et à la projection en 2 dimensions d’unobjet en 3D. La reconstruction en 3D des segments anatomiques à partir d’images biplanes acquises en position debout doit permettre de s’affranchir de ces biais, au prixd’une irradiation modérée. La 1ère partie de ce travail a posé la question de l’utilisationen pratique clinique courante des reconstructions en 3D issues de ce système, et a permis de valider la reproductibilité de celles ci ainsi que de donner des valeurs de référence de ces paramètres mesurés en 3D. La 2ème partie a consisté en l’adaptationd’un modèle de reconstruction de pieds de l’adulte à ceux de l’enfant, a permis devérifier la reproductibilité des données obtenues, ainsi que de rapporter des valeurs préliminaires de paramètres de mesures radiologiques. Enfin, la 3ème partie a étudié l’analyse complète de pieds pathologiques (pied bot varus équin) associant l’examenclinique, la morphologie radiologique (obtenues par EOS®) et la fonction du pied lors d’une analyse de la marche. Nous en concluons que si cette analyse combinée paraîtcapitale, des difficultés persistent, en particulier dans le choix du modèle pour l’analyse de la marche, les modèles les plus complets actuels étant grévés d’une incertitude liée au placement des marqueurs trop importante. / Clinical examination and standard X-rays of the lower limbs and feet have biases related to reproducibility and to 2-dimensional projection of a 3D object. The 3Dreconstruction of the anatomical segments from biplanar images acquired in a standingposition should make possible to get rid of these biases, at the cost of moderate irradiation. The 1st part of this work asked the question of the use in current clinical practice of the reconstructions in 3D resulting from this system, and allowed validationof the reproducibility of these while giving reference values of the measured parameters in 3D. The 2nd part consisted in the adaptation of a model of reconstruction of the feet of the adult to those of the child, and aimed to check the reproducibility of the data obtained, and to report preliminary values of parameters of measurements. Finally, the 3rd part studied the feasibility of a complete analysis of pathological foot (congenital clubfoot) combining clinical examination, radiological morphology (EOS® images) andfoot function with gait analysis. We conclude that while this combined analysis appears to be critical, difficulties remain, particularly in the choice of the model for walkinganalysis, with the current full-scale models being overwhelmed by uncertainty related tothe placement of markers.

A digital twin facilitates the means to monitor, understand, and optimize the functions of the physical entity and provides continuous feedback to improve quality of life, and Medical Cyber-Physical Systems (MCPS) is an integral part of this vision. Many studies focus on human motion to digitize data for further analysis. The literature review presented here emphasizes on gait analysis and gait events detection using wearable devices, which compare results by testing on different groups of individuals. Amongst those, there is a focus on digitizing activities for athletes and sports activities. However, there is a lack of research that address configurability for this type of MCPS. Adding new physical devices to an established MCPS requires manual configuration. Recent studies either solve the issue of users’ mobility by providing a wireless solution with local storage, or sacrifice mobility in order to provide real-time information through wired communication. However, group physical activity applications, such as sports coaching and group physiotherapy, use customized devices that need to be automatically configured in the system. In addition, these systems need to support mobility and real-time data presentation. To solve this problem, a framework is proposed to design a wellbeing Cyber-Physical System (CPS) that focuses on system configurability, providing real-time data of body sensor networks while supporting wireless and mobile communication. A communication protocol is proposed to allow seamless integration and communication of system components, and to enable bandwidth-conscious data transmission. As a proof of concept, a configurable CPS for gait activities monitoring is designed to read, visualize, and backup spatiotemporal data from one or more multi-sensory physical devices over conventional Wi-Fi and in real-time. Two experiments were performed using the implemented CPS. The first experiment was performed outdoors and tested if the CPS components would recognize each other and work seamlessly over foreign networks while providing usable information. The second experiment was performed in collaboration with the Health Sciences Department using our system and the Tekscan Strideway gait mat simultaneously to compare results and to ensure accuracy. In addition, this experiment tested configurability of the system by using different measurement devices for different users.

<p>In 3D and 2D animations walk cycles of characters appear very frequently and are an important way of expressing various aspects of the story told. However walk cycles are tedious and time consuming to animate. In this work an Autodesk MAYA plug-in has been developed, that aims at automating this process. The walk cycle plug-in can be highly beneficial for animators when creating convincing walk cycles in a fast and simple way. The plug-in calculates the right values for each phase in the walk cycle. The GUI of the plug-in makes it easy to provide the required input parameters. In addition, the plug-in allows the animation of a character to walk along a chosen path.</p>

No description available.

The human foot contributes significantly to the function of the whole lower extremity during standing and locomotion. Nevertheless, the foot and ankle often suffer injuries and are affected by many musculoskeletal and neurological pathologies. The overall aim of this thesis was to evaluate gait parameters and muscle function change due to foot and ankle injury, malalignment and co-contraction. Using 3D gait analysis, analytical analyses and computational simulations, biomechanical consequences of gait impairment at the ankle and foot were explored in ablebodied persons and in patient groups with disorders affecting walking. We have characterized gait patterns of subjects with ankle fractures with a modified multi-segment foot model. The inter-segmental foot kinematics were determined during gait in 18 subjects one year after surgically-treated ankle fractures. Gait data were compared to an age- and gender-matched control group and the correlations between functional ankle score and gait parameters were determined. It was observed that even with fairly good clinical results, restricted range of motion and malalignment at and around the injured area were found in the injured limb. Moment-angle relationship (dynamic joint stiffness) - the relationship between changes in joint moment and changes in joint angle - is useful for demonstrating interaction of kinematics and kinetics during gait. Ankle dynamic joint stiffness during the stance phase of gait was analyzed and decomposed into three components in thirty able-bodied children, eight children with juvenile idiopathic arthritis and eight children with idiopathic toe-walking. Compared to controls, the component associated with changes of ground reaction moment was the source of highest deviation in both pathological groups. Specifically, ankle dynamic joint stiffness differences can be further identified via two subcomponents of this component which are based on magnitudes and rates of change of the ground reaction force and of its moment arm. And differences between the two patient groups and controls were most evident and interpretable here. Computational simulations using 3D musculoskeltal models can be powerful in investigating movement mechanisms, which are not otherwise possible or ethical to measure experimentally. We have quantified the effect of subtalar malalignment on the potential dynamic function of the main ankle dorsiflexors and plantarflexors: the gastrocnemius, soleus and tibialis anterior. Induced acceleration analysis was used to compute muscle-induced joint angular and body center of mass accelerations. A three-dimensional subject-specific linkage model was configured by gait data and driven by 1 Newton of individual muscle force. The excessive subtalar inversion or eversion was modified by offsetting up to ±20˚ from the normal subtalar angle while other configurations remain unaltered. We confirmed that in normal gait, muscles generally acted as their anatomical definitions, and that muscles can create motion in many joints, even those not spanned by the muscles. Excessive subtalar eversion was found to enlarge the plantarflexors’ and tibialis anterior’s function. In order to ascertain the reliability of muscle function computed from simulations, we have also performed a parametric study on eight healthy adults to evaluate how sensitive the muscle-induced joints’ accelerations are to the parameters of rigid foot-ground contact model. We quantified accelerations induced by the gastrocnemius, soleus and tibialis anterior on the lower limb joints. Two types of models, a ‘fixed joint’ model with three fixed joints under the foot and a ‘moving joint’ model with one joint located along the moving center of pressure were evaluated. The influences of different foot-ground contact joint constraints and locations of center of pressure were also investigated. Our findings indicate that both joint locations and prescribed degrees-of-freedom of models affect the predicted potential muscle function, wherein the joint locations are most influential. The pronounced influences can be observed in the non-sagittal plane. Excessive muscle co-contraction is a cause of inefficient or abnormal movement in some neuromuscular pathologies. We have identified the necessary compensation strategies to overcome excessive antagonistic muscle cocontraction at the ankle joint and retain a normal walking pattern. Muscle-actuated simulation of normal walking and induced acceleration analysis were performed to quantify compensatory mechanisms of the primary ankle and knee muscles in the presence of normal, medium and high levels of co-contraction of two antagonistic pairs (gastrocnemiustibialis anterior and soleus-tibialis anterior). The study showed that if the co-contraction level increases, the nearby synergistic muscles can contribute most to compensation in the gastrocnemius-tibialis anterior pair. In contrast, with the soleus-tibialis anterior co-contraction, the sartorius and hamstrings can provide important compensatory roles in knee accelerations. This dissertation documented a broad range of gait mechanisms and muscle functions in the foot and ankle area employing both experiments and computational simulations. The strategies and mechanisms in which altered gait and muscles activation are used to compensate for impairment can be regarded as references for evaluation of future patients and for dynamic muscle functions during gait. / QC 20120514

In this master thesis the connection between the two major parts of an osseointegrated prosthesis system for lower limb amputees has been investigated by finite element (FE) analysis. The prosthesis system is developed by Integrum and the current design consists of a fixture, which is integrated in the residual bone, an abutment that penetrates the skin and an abutment screw that holds the parts together. The connection between the fixture and the abutment has a hexagonal section and a press-fit section that together form the connection. Due to wear and fracture problems it is desired to improve the connection. A tapered connection could be an alternative and three different taper angles, the effect of the length of the taper and the smoothness of the outer edge of a tapered fixture have been investigated. The results show that the taper has potential to function well and that a longer connection will give lower stresses in the system, but further investigations are needed.

Gait analysis is one of the primary applications of biomechanics and deals with scientific description of human locomotion, which is a qualitative concept as observed through the human eye. METU Gait Analysis Laboratory has been operating in various fields of gait and motion analyses since 1999. Although several studies have previously been undertaken about METU Gait Analysis System, until now, the effects of methodology and protocol related system parameters on kinematic analysis results have not been fully and exhaustively investigated. This thesis presents an assessment on sensitivity and compatibility of METU Gait Analysis Protocol to variations in experimental methodology and implementation of various joint center estimation methods, performed through investigation of the resulting joint kinematics. It is believed that the performance and reliability of METU Gait Analysis System will be improved based on the findings of this study.