L'analyse du comportement du système musculo-squelettique est indispensable à la compréhension de pathologies ou de l'efficacité du geste sportif. Les modèles, représentants un sujet moyen, permettent l'identification de tendance. Cependant, leurs résultats sont limités à la plage de population qu'ils représentent. Il est donc nécessaire d'adapter leurs géométries et propriétés mécaniques afin de simuler le plus fidèlement possible le comportement biomécanique. L'IRM est l'outil de référence pour la construction de modèle personnalisé tridimentionnel. Cependant, son coût, sa disponibilité et les méthodes de reconstructions limitent son utilisation. Récemment, les développements de la stéréoradiographie, avec le système EOS®, et des techniques ultrasonores, avec l'élastographie ShearWave, ouvrent de nouvelles voies pour la personnalisation des modèles. Le but de ce travail était de proposer une nouvelle méthode pour la construction d'un modèle musculo-squelettique personnalisé, en position érigée, du membre inférieur combinant stéréoradiographie et ultrasons. Tout d'abord, des repères osseux robustes sur images IRM ont été définis pour construire un modèle de référence en position debout. Ensuite, la personnalisation de la géométrie osseuse et de l'enveloppe externe est obtenue par stéréoradiographie. Ces premières informations personnalisées sont utilisées pour estimer la géométrie des muscles. Ce modèle pré-personnalisé est déformé pour correspondre à la géométrie réelle des muscles obtenue par échographie. Cette méthode possède plusieurs avantages. Elle passe outre l'assemblage de coupes échographiques et de supprime la segmentation manuelle complète des coupes. Enfin, un protocole de mesure des propriétés mécaniques par élastographie ShearWave a été présenté. Les propriétés élastiques des muscles du membre inférieur peuvent alors être définies. / The analysis of the behavior of the musculoskeletal system is essential to understand diseases or effectiveness of the sporting gesture. Models, which represent a 50-percentile subject, allow tendencies identification. However, results are limited to the range of people they represent. Their geometry and mechanical properties must be personalized to simulate as closely as possible the biomechanical behavior. MRI is the reference device for the construction of three-dimensional personalized models. However, the cost, the availability and methods of reconstruction limit its use. Recent developments in stereoradiography, with the EOS® system, and in ultrasonic field, with ShearWave elastography, open up new horizons. The aim of this work was to propose a new method for building a personalized musculoskeletal model of lower limb combining stereoradiography and ultrasound, in standing position. First, robust bony frame on MR images were defined to build a reference model. Then, the personalized bones and external envelope geometries were obtained by stereoradiography. This first personalized information was used to estimate muscles geometry. This pre-personalized model was deformed to match the real muscle geometry obtained by ultrasound. This method has several advantages. It overrides the assembly of ultrasound cuts and removes the complete manual segmentation. Finally, a protocol for measuring the mechanical properties ShearWave elastography was introduced. Thus, the muscles elastic properties of the lower limb can then be defined in the model.

Abstract available in the Journal of Strength and Conditioning Research

Traditionally, the mechanical testing of ankle-foot orthoses (AFOs) has been performed with simple limb surrogates, typically with a single axis ankle joint and rigid foot and shank components. Since many current AFO designs allow 3D motion, a surrogate lower limb (SLL) that provides anatomically similar motion in all planes is needed to enable realistic load testing and cyclic testing in a controlled manner. The aim of this thesis was to design, fabricate and test a novel SLL that provides anatomically realistic 3D foot motion, based on a consensus of the passive lower limb range of motion (RoM) found in the literature. The SLL design was inspired by the Rizzoli model, sectioning the lower limb into five segments (shank, hindfoot, midfoot, forefoot, toes). Ball and socket joints were used for the shank-hindfoot, hindfoot-midfoot, and midfoot-forefoot. Forefoot-toes used a hinge-type joint. 3D printed flexible thermoplastic polyurethane (TPU) snap-fit connectors connected the 3D printed nylon foot blocks. A threaded ball stud connected the shank shaft and hindfoot. This shank shaft was surrounded by a 3D printed polylactic acid (PLA) shank cover. The foot was cast in silicone rubber to emulate soft tissue, with a PLA custom mould based on a Össur prosthetic foot cover model. The SLL was successfully designed for easy fabrication using readily available techniques, materials, and components. Only the metal shaft required additional machining. 3D printed components used an affordable 3D printer (Artillery Sidewinder X1), and readily available nylon, PLA, and TPU. Using motion capture testing, SLL foot rotation angles were found to be within standard deviation of mean foot passive rotation angle ranges found in the literature, showing that most joints were within 5° of target maximum rotation angles. With load testing, the SLL was shown to survive static loads representing 1.5 times body weight for a 100 kg individuals and cyclic loads representing normal gait loading for 500,000 cycles.

Les personnes amputées de membre inférieur (PAMI) sont très diversifiées. Ils’agit d’une population hétérogène, tant par ses origines que par ses niveaux d’amputation, ses capacités et ses projets de vie. A ces profils variés s’ajoutent une multitude de composants prothétiques ainsi que les différentes combinaisons possibles entre ces composants. Il est également important de prendre en compte les différents environnements auxquels la PAMI est confrontée quotidiennement. La Classification Internationale du Fonctionnement (CIF 2001) a été créée par l’Organisation Mondiale de la Santé et repose sur un modèle multidimensionnel. Elle est constituée de deux grandes parties : le fonctionnement d’une part et les facteurs contextuels d’autre part. Ce modèle est capable de décrire de manière globale les modifications de fonctionnement (handicap) à partir d’un problème de santé quelconque. Ainsi, une grande quantité d’informations peut être obtenues à partir du modèle de la CIF. Néanmoins, il demeure nécessaire de développer de nouveaux outils pour mieux exploiter ce modèle afin de le rendre plus intelligible et utilisable en pratique clinique courante. Pour cela, nous nous proposons d’utiliser l’Extraction de Connaissances à partir des Données (ECD). L’ECD est un processus non trivial d'identification des structures inconnues, valide et potentiellement exploitable dans les bases de données, qui permet de transformer un maximum d’informations en connaissances facilement exploitables. A partir du modèle de la CIF et conjointement avec des méthodes d’ECD, l’objectif de cette thèse est de caractériser un groupe de PAMI expertes en termes de capacités locomotrices. Ce groupe et sa liste d’indicateurs pertinents reposant sur le modèle de la CIF ont été déterminés. Ils servent de référence pour la comparaison d’autres PAMI et peuvent guider la prise en charge de cette population particulière. / The subjects with a lower-limb amputation (LLA) compose a heterogeneouspopulation, by their amputation origins, by their amputation levels, by their abilities and by their life projects. To these various LLA’s profiles we could add a multitude of prosthetic components and the combination of these components. It is also important to take into account the different environments, which the LAA are confronted daily. The International Classification of Functioning, Disability and Health (ICF 2001) was created by the Word Heath Organization and is based on a multidimensional model. The ICF is constituted by two domains: the functioning on one hand and the contextual factors on the other hand. This comprehensive-global model is able to describe the functioning (disability) from any health problem. However it remains necessary to develop new tools to better use the ICF model making it more intelligible and useful in clinical practice. For this, we proposed to use the Knowledge Discovery in Database (KDD). KDD is a non-trivial process of identification of unknown, valid and potentially-exploitable structures in database. KDD permits to transform a maximum of information in easy-exploitable knowledge. From the ICF model conjoint with KDD methods, the aim of this thesis was to characterize an expert group of LLA in terms of locomotion capacity. This group and its list of relevant indicators, based on the ICF model, were determined. They can be used as a reference to compare with others LLA improving making decision of this particular population.

Objectives: Our thesis is focused on correlation of lateral (side) preferencies of lower limbs and quality of sensorimotor control. Our aim is to figure out whether there is difference in laterality of sensorimotor control of lower limbs and if so, whether there is correlation with side preferency. Methods: Study is made on 18 volunteers. We tested somatosenzoric system, specifically two-point discrimination, graphesthesia, pallesthesia, statesthesia, kinesthesia. We used a questionnare to determine side preferency of lower limbs. We used paired sample t- tests, with level of importance p=0,05. Results: According to t-tests, there are no differencies in sensorimotor control in lower limbs. According to those results, it is not possible to determine the difference in sensorimotor control due to lower limb preferency. Summary: There is no difference in sides in sensorimotor control of lower limbs.

Changes in the external surfaces on the lower limb bones can be caused by various taphonomic factors. It is important for our work how these changes will affects. The aim of the work was to process and subsequently evaluate the changes in the external surfaces on the lower limb bones. For analyses we chose set of adults from 2nd church burial ground Pohansko near Břeclav, we chose specifically braid of the lower limbs (cingulum membri inferioris) and free lower limb (pars libera membri inferioris). We wrote down taphonomic changes into prepared protocols, changes were typologically about damages and color changes. We used programs InkScape and AdobePhotoshop to transform paper protocols into digital form. Heat maps are outputs from this programms through them we are able to see incidence rate of individual changes. We most often detected the occurrence of an orange color on the bones of the lower limbs, so we focused on its cause. We found an increased content of silicon and aluminum in its chemical composition, so we assume that it could be an aluminosilicate weathering product. Key words: Pohansko, taphonomy, taphonomic factors, bone surface, lower limb

Title: The effect of exercise with blood flow restriction on the development of muscle strength Objectives: The aim of this work was to assess the magnitude of the effect of exercise with blood flow restriction on the development of muscle strength on the basis of a systematic research and to determine the main factors that moderate this increase. Methods: Primary sources were searched in the scientific databases Academic Search Ultimate, Web of Science and Taylor and Francis. Individual training interventions were found in the included studies. Based on the training interventions, possible moderating factors of the magnitude of the effect on the development of muscular strength of the upper or lower limbs were defined. From the results of the studies, the effect size values of Cohen's d and Hedge's g were calculated. The influence of concrete parameters of application of the vascular occlusion and blood flow restriction exercise on the magnitude of the effect was evaluated on the basis of correlation analysis. Results: A total of 27 studies were included in this diploma thesis, in which 39 different trainings using blood flow restriction exercises were found and included. Based on the correlation analysis, no direct relationship was found between the exercise parameters and the magnitude of the...

A research report submitted to the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, in partial fulfillment of the requirements for the degree of Master of Science in Physiotherapy. Johannesburg, 2015 / The Human Immunodeficiency Virus (HIV) has been found to cause muscle weakness, wasting and peripheral neuropathies. The specific relationship between lower limb muscle strength and lower limb function in HIV positive patients on Highly Active Antiretroviral Therapy (HAART) has not been examined. The aims of the current study were to establish lower limb muscle strength in HIV positive patients on HAART, establish lower limb muscle strength in HIV negative people, compare lower limb muscle strength between patients who are HIV positive on HAART and HIV negative people, establish lower limb function in patients who are HIV positive on HAART and to establish the relationship between lower limb muscle strength and lower limb function in patients who are HIV positive on HAART. A cross-sectional, descriptive study design was used. Dynamometry was used to measure lower limb muscle strength. The lower Extremity Functional Scale (LEFS) was used to determine lower limb function. A pilot study was done to establish the feasibility and proficiency required to perform hand held dynamometry. Intra and inter-rater reliability were also determined during the pilot phase. Intra and inter-rater reliability were high for the raters' measurement of lower limb muscle strength using a dynamometer with 'r' values of 0.97. For HIV positive patients on HAART, 19% (n=22) were in the age band 45-49years, whereas 33% (n=10) of HIV negative subjects were in age interval 25-29 years. Those over 45 years who were HIV positive on HAART constituted 57% (n=64) of the sample. The mean muscle strength obtained ranged from 9.30kg/m2 in ankle dorsiflexors to 15.80kg/m2 in hip extensors in HIV positive people on HAART for an average of 4 years while knee flexors generated 11.81 kg/m2 and knee extensors generated 15.36kg/m2 in this cohort.Jn the HIV negative matched group, the mean muscle strength ranged from 11.20 kg/m2 in ankle dorsiflexors to 17.70 kg/m2 in hip extensors while knee flexors generated 12.65kg/m2 and knee extensors generated 17.07kg/m2. The majority 78% (n=88) of HIV positive patients on HAART had no difficulty with lower limb function while 22% (n=17) had difficulty. Only 2% (n=2) of HIV positive patients on HAART had quite a bit of difficulty with lower limb functional activities after measurements using the Lower Extremity Functional scale (LEFS). A multiple linear regression showed that there was a positive correlation coefficient of r=0.71 (p-value= 0.00) between lower limb muscle strength and lower limb function. The coefficient of determination 0.50 means that 50% of the changes in lower limb function are attributable to lower limb muscle strength. Gender, employment status and mode of transport also positively affected lower limb function. A detailed regression model showed that lower limb ankle plantar flexors contributed the most to lower limb function in this cohort. This is contrary to International literature which states that hip and trunk muscles are the most active in HIV negative people during lower limb functional activities. That plantar flexors contribute the most in lower limb functional activities instead of hip and trunk muscles confirms the existence of proximal weakness in this cohort which was established by other researchers. This study highlighted that 50% of lower limb function is a result of lower limb muscle strength in HIV positive people on HAART attending an outpatient clinic in Mutare, Zimbabwe. Ankle plantar flexors instead of hip flexors were the most active muscle group in lower limb functional activities in this cohort. It therefore means exercise prescription to activate/strengthen hip flexors and other proximal muscles will improve this population's lower limb functional activities since progressive resisted aerobic exercises have been proved to strengthen muscles. / AC2016

Of the 795,000 people that suffer a stroke in the United States every year, 65% experience hemiparesis. Foot drop is a common gait pathology in people with lower-limb paresis and is often caused by neuropathy of the peroneal nerve that innervates the muscles responsible for ankle dorsiflexion. Foot drop can impede toe clearance and increase the risk of falling, the leading cause of injury among adults ≥65 years. Lower-limb robotic exoskeletons have been used for gait training and can aid with walking, but current devices on the market can be heavy, expensive, and constrained to in-clinic use. Soft wearable robotic devices offer a lightweight and cost-effective alternative to traditional lower-limb exoskeletons. In particular, soft pneumatic systems have the potential to provide a high power-to-weight ratio making them ideal for a wearable application. The soft pneumatic exosuit consists of a footplate to collect air, storage to temporarily house the collected air, and two pneumatic actuators to provide an assistive torque around the wearer’s ankle joint while walking. EMG and IMU sensors were integrated to control the opening and closing of solenoid valves so that assistive torques could be applied to the ankle joint at optimal moments during the gait cycle. Preliminary validation of the soft pneumatic exosuit on a healthy participant demonstrated that the system could successfully deliver the air required to contract the actuators when the EMG sensors detected an increase in muscle activity. These results demonstrate that the current soft pneumatic exosuit appears to be a promising alternative to current rehabilitation exoskeletons on the market while remaining portable and low-cost. / 2025-05-24T00:00:00Z

Specific rehabilitation is a key period for a lower-limb amputee patient. While learning how to walk with a prosthesis, the patient needs to avoid any gait compensations that may lead to future comorbidities. To reach a gait pattern close to the one of a healthy person, objective data may be of great help to complement the experience of the clinician team. By using 6 IMUs located on the feet, shanks and thighs accompanied by 3 accelerometers on the pelvis, sternum and head, data could be recorded during walking exercises of 7 rehabilitation sessions of a patient. To compute the absolute symmetry index of the stance phase duration and the stride duration all over the instrumented sessions, the gait events defining the transitions between gait phases were determined thanks to several algorithms. By first comparing the error obtained in the calculation of the stance phase duration with all tested algorithms as compared to the data from pressure insoles considered as a reference system, the algorithm developed by Trojaniello and collaborators [1] was found to be the most adapted to this situation. Using this algorithm on the data from all sessions highlighted the possibility to detect changes in the symmetry of stance phase duration and stride duration, that are relative to the gait quality. This means that IMUs seem to be able to monitor the progress of a patient during his rehabilitation. Hence, IMUs have proven themselves to be a system of great interest in the analysis of the gait pattern of a lower-limb amputee patient in rehabilitation, by allowing for an embedded measurement of much more parameters than the pressure insoles, whose calibration constituted a real limitation.