Walking disorders are one of the most visible symptoms of multiple sclerosis (MS). Multiple sclerosis (MS) is a chronic autoimmune neurodegenerative disease of the central nervous system that is the most common cause of disability of young adults. Walking disorders are one of the most common motor problems that accompany this disease, which patients themselves perceive as the most limiting. Walking disorders can be caused by many symptoms of MS such as: muscle weakness, spasticity, sensory disturbances, visual disturbances, sphincter problems, cognitive dysfunction, fatigue and thermosensitivity. Measuring of various gait parameters (most often speed and endurance) also helps to monitor the effects of treatment and to evaluate the progression of the disease. Even in patients with minimal neurological symptoms it is possible to detect deterioration of gait parameters. Realized studies have shown that subjectively perceived improvement in gait after treatment with natalizumab can be objectified with the aid of assessment of walking parameteres. Similarly, a functional gait test can be used to assess the therapeutic response (and thus evaluate the cost effectiveness of treatment) to symptomatic treatment with fampridine. As a physiotherapist, I was also interested in the possibility of influencing...

The following work presents a novel, overground robotic gait trainer: the mobile Tethered Pelvic Assist Device, or mTPAD. The mTPAD is a parallel, cable-driven platform that can apply three-dimensional forces and moments to the user’s pelvis as they walk overground. These forces and moments applied to the pelvis can be timed to the user’s gait and motivated through gait deficits to target specific motions or gait adaptations. An overview of both traditional and robotic gait training is given as an introduction in Chapter 1. The state-of-the-art pelvic robotic gait trainers are discussed, and the need for an overground device that can apply timed forces and moments to the pelvis is highlighted. The design of the mTPAD is covered in Chapter 2. The mechanical structure and the novel controller are discussed and validated through experiments with human participants. The mTPAD device is evaluated on its transparency, accuracy of pelvic localization, and ability to apply specific forces. Chapter 3 illustrates a continuous moment that is applied to the pelvis and synchronized with the user’s gait cycle. The controller is evaluated on its accuracy and ability to alter pelvic kinematics and muscle activations in a group of neurotypical adults. Chapters 4 and 5 highlight the mTPAD’s ability to alter gait characteristics and muscle responses of two groups that exhibit gait deficits: stroke survivors and children with Cerebral Palsy. By evaluating the effects of different force and moment profiles on individuals who may benefit from gait training, this work aims to illustrate the mTPAD’s potential as an overground gait training tool.

Le rôle respectif des ganglions de la base (GB) et de la région locomotrice dans le contrôle locomoteur et postural n'est pas établi chez l'homme. Au sein de ces circuits, le noyau sous-thalamique (NST) et le noyau pédunculopontin (NPP) semblent impliqués dans le pattern locomoteur et le maintien de l'équilibre. En effet, chez les patients avec maladie de Parkinson (MP), caractérisée par une perte des neurones dopaminergiques et représentant un modèle de dysfonctionnement des GB, des dysfonctionnements de l'activité du NST seraient à l'origine d'un freinage du mouvement, jusqu'au blocage moteur (freezing de la marche-FOG). Dans le NPP, des lésions cholinergiques sont retrouvées chez les patients MP avec des chutes. Dans ce travail de recherche nous avons étudié le rôle du NST et les effets de la modulation de l'activité du NPP sur les étapes de l'initiation de la marche (GI) chez les patients avec MP. Nous avons retrouvé une synchronisation dans la bande de fréquence alpha précédant l'exécution du pas, en cohérence avec le NPP. La stimulation à basse fréquence du NPP améliore le contrôle postural. Ces données suggèrent que le NST est impliqué dans la préparation de la GI, et que le NPP a un rôle dans le contrôle postural chez l'homme. Dans une seconde partie, nous avons examiné le rôle des lésions du circuit cortex-GB-NPP dans la survenue du FOG et des chutes chez des sujets âgés non-parkinsoniens et démontré une lésion sélective de ce circuit chez ces sujets. Finalement, l'ensemble de ces données confortent les hypothèses physiopathologiques à l'origine des troubles de la marche et de l'équilibre chez les patients MP avec lésion/dysfonction du circuit cortex-GB-NPP. / The respective roles of basal ganglia (BG) and the mesencephalic locomotor region (MLR) in the postural control and locomotion are not clearly established in humans. In these circuits, the subthalamic nucleus (STN) and the pedunculopuntine nucleus (PPN), two interconnected structures, appear to be involved in the locomotor pattern control and postural maintenance. Indeed, in patients with Parkinson’s disease (PD), characterized by a progressive loss of dopaminergic neurons and representing a model of dysfunction of the BG, there are dysfunctions of STN activity that could cause braking of movement underlying motor block (freezing of gait-FOG). In the PPN, greater loss of cholinergic neurons is observed in PD patients with falls. In this research, we studied STN activity and the effects of modulating the PPN activity during the stages of gait initiation (GI) in patients with PD. We found a modulation of activity of the STN with synchronization in the alpha frequency band before the postural adjustments and the execution of step, with PPN coherence. Low frequency stimulation of the PPN improved postural control with no significant effect on the locomotion. These data suggest that the STN is involved in the preparation of GI and the PPN has a leading role in postural control in humans. In a second part, we examined the role of the cortex-basal ganglia-PPN circuit in FOG and falls in a non-parkinsonian elderly population and demonstrated a selective lesion of this circuit in these subjects. Taken together, these data support the pathophysiological hypothesis for the origin of abnormal gait and balance in patients with PD, with lesion and/or dysfunction of the cortex-BG-PPN.

published_or_final_version / abstract / toc / Orthopaedics and Traumatology / Master / Master of Philosophy

Orientador: Irenilza de Alencar Naas / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola / Made available in DSpace on 2018-08-14T16:50:04Z (GMT). No. of bitstreams: 1 Cordeiro_AlexandraFerreiradaSilva_M.pdf: 698775 bytes, checksum: 00cd96699cf75d7552399f75087669d7 (MD5) Previous issue date: 2009 / Resumo: O Brasil é hoje um dos maiores produtores e exportadores de carne de frango no mundo, mas para continuar nessa posição é necessário respeitar o bem-estar animal e manter baixos custos de produção. Problemas locomotores impedem que a ave se movimente livremente e, com isso, acesse os equipamentos necessários a sua sobrevivência: comedouro e bebedouro, prejudicando seu bem- estar e sua produtividade. A hipótese dessa pesquisa é que frangos de corte produzidos em condições de estresse apresentam problemas locomotores. O objetivo desse trabalho foi avaliar deficiências locomotoras em frangos de corte alojados em condições de estresse. Para tanto, foram realizados dois experimentos, sendo o primeiro a determinação da pressão plantar de aves de 28, 35, 42, e 49 dias, o qual foi realizado no Centro de Tecnologia da Universidade estadual de Campinas, São Paulo, Brasil. Essa medida foi determinada por sensores localizados sob uma esteira enquanto as aves caminhavam sobre ela, nesta ocasião também foi determinado o gait score dessas aves. As mais pesadas tiveram mais dificuldade de andar e tiveram maior valor de gait score. Não houve diferença significativa (p = 0,05) no pico da força das patas direito e esquerdo para aves com gait score 0 e 1; entretanto, para frangos mais pesados com gait score 2 houve desbalanço severo no pico das forças entre as patas. A força total expressa em porcentagem do peso vivo aumentou com a idade como esperado, mostrando uma correlação positiva com o gait score para as aves selecionadas. A deficiência de locomoção foi automaticamente detectada devido ao movimento desigual, como seu peso não foi distribuído igualmente nas patas durante caminhada. O segundo experimento constou de observação visual no campo, em granjas da região de Campinas-SP, com determinação do gait score em aves de 28, 35, e 42 dias. Neste experimento o gait score foi avaliado por três metodologias, aves estimuladas a andar, aves sem estímulo para andar e em 10 aves ao acaso dentro do galpão. Não foram encontradas evidências de interação entre os fatores Metodologia e Idade. Há influencia significativa da Metodologia sobre a determinação do gait score. A metodologia de 10 aves ao acaso foi a que se apresentou menos confiável. Os resultados de gait score foram menores na metodologia com estímulo para as aves andar. Entretanto nas três avaliações realizadas e em todas as idades, os resultados de gait score foram piores que o aceitável, sendo que a maior freqüência para gait score 0 (padrão normal) encontrada nesta pesquisa foi de 50%. Estes resultados poderiam ser atribuídos as condições de estresse ambiental inapropriadas em que os frangos foram produzidos. / Abstract: Brazil is today one of the largest poultry meat producer and exporter of the world; however, in order to continue in this production level and quality it is needed to apply animal welfare principles maintaining the same production costs. Locomotors problems keep away the bird from moving freely and to access the needed equipments for its survival: feeder and drinker, reducing their welfare and productivity. The hypothesis of this research it is that Brazilian poultry production presents locomotors problems. The objective of this research was is to evaluate locomotors deficiencies in broiler chicken housed under stressful conditions. For that two experiment were done, the first was the determination of the feet pressure of broiler with the ages of 28, 35, 42 and 49 days. This first experiment was carried out at the Center for Technology, State University of Campinas, SP. The feet force measurement was determined by sensors over a mat while the birds walked over it, and at the same time the gait score was also determined. The heavier birds had more difficult in walking and presented higher gait score. No significant difference was found (p = 0.05) in the force peak of the right and left feet for the birds with gait score 0 and 1; however, older broilers with gait score 2 presented severe unbalance in the peak of force in both feet. The total force expressed as the percentage of the live weight increased with age as expected showing a positive correlation with the gait score of the tested broilers. The locomotion deficiency was automatic detected due to the unbalanced movement as the weight was not equally distributed in both legs during walking. The second experiment constituted of a visual observation in the field, in commercial broiler farms in the region of Campinas, SP, for determining the gait score of birds 28, 35 and 42 days old. In this trial the gait score was estimated in three ways, broilers stimulated to walking, birds without stimulus for walking and broilers chosen randomly inside the housing. No evidence of interaction between the factor Methodology and Age. Significant influence of Methodology over the determination of gait score was found. The methodology of chosen 10 bird at random was the one least reliable. The results of gait score were lower when using the methodology that stimulated the birds to waking. However, in the three evaluations and in all ages the results of gait score were worst than the acceptable, since the frequency of gait score 0 (normal pattern) found in this research was 50%. These results could be accredited to the inappropriate ambient harsh conditions the broilers were reared. / Mestrado / Construções Rurais e Ambiencia / Mestre em Engenharia Agrícola

<p>Cilj rada: Posmatrano je da li postoji povezanost kliničkih parametara, bihejvioralnih simptoma i postignuća na testovima kognitivnih funkcija sa karakteristikama hoda kod obolelih od Parkinsonove bolesti. Analizirana je i povezanost nalaza hiperehogenosti strukture substantia nigra dobijenog transkranijalnim parenhimskim ultrazvukom sa karakteristikama hoda.Materijal I metode: Istraživanjem je obuhvaćeno 60 obolelih od Parkinsonove bolesti (22 žene i 38 mu&scaron;karaca, sa trajanjem bolesti 5,06&plusmn;4,54 godina, ukupnim UPDRS 39,76&plusmn;36,65, UPDRS III 24,28&plusmn;15,18) koji su prema stadijumu bolesti po Hen i Jarovoj skali (H&amp;Y) podeljeni u tri podgrupe sa po 20 ispitanika: H&amp;Y 1, 2 i 3. Kontrolnu grupu činilo je 35 zdravih ispitanika (19 žena i 16 mu&scaron;karaca) koji se od grupe obolelih nisu razlikovali u pogledu godina starosti (oboleli 64,21&plusmn;6,92 godina, zdravi 63,45&plusmn;7,75, p=0,832) i godina obrazovanja (oboleli 12,63&plusmn;3,16 godina, zdravi 12,57&plusmn;2,87, p=0,954). Iz analize su isključeni ispitanici čiji je skor MMSE bio manji od 24. Procena težine motornih znakova Parkinsonove bolesti vr&scaron;ena je Unifikovanom skalom za kvantifikovanje Parkinsonove bolesti, treći deo (UPDRS III). Za globalnu procenu kognicije je kori&scaron;ćena Revidirana Adenbrukova kogntivna skala (ACE- R), a za procenu egzekutivnih funkcija su kori&scaron;ćeni baterija za procenu frontalnih funkcija (FAB) i Egzekutivni intervju (EXIT-25). Za evaluaciju depresije kori&scaron;ćene su Hamiltonova skala za procenu depresije (HAM- D) i Bekova skala depresivnosti (BDI II), za procenu anksioznosti Hamiltonova skala za procenu anksioznosti (HAM- A), a za procenu apatije Skala apatije (AS).Određivanje vremenskih i prostornih parametara hoda vr&scaron;eno je pomoću GAITRite sistema, tokom &bdquo;on&rdquo; perioda. Analizirano je osam parametara hoda: vreme dvokoraka (CT), dužina dvokoraka (SL), vreme zamaha (ST) i vreme dvostrukog oslonca (DS), kao i njihovi koeficijenti varijacija (CV). Posmatran je i uticaj dvostrukog zadatka na parametre hoda. Kao dodatni zadatak tokom hoda primenjen je kognitivni zadatak (oduzima -7 tokom hoda), motorni zadatak (nosi ča&scaron;u punu vode) i kombinovani zadatak (oduzima i nosi ča&scaron;u istovremeno). Veličina hiperehogenosti substantia nigra merena je transkranijalnim parenhimskim ultrazvukom. Rezultati: U poređenju sa zdravim vr&scaron;njacima, oboleli od Parkinsonove bolesti imali su značajno izraženiji varijabilitet koraka pri hodu bez zadatka (skraćen SL, povećan CVSL i CVCT, varijabilitet koraka bio je jo&scaron; izraženiji, dok je pri motornom zadatku postojala i značajna razlika DS i CVDS (p&lt;0,05), tj. parametara kojima se izražava ravnoteža koraka. U uslovima kombinovanog zadatka ove razlike su se potencirale. Parametri hoda (SL, VCSL, CVCT I CVST) minimalno su se razlikovali kod obolelih u najranijim stadijumima bolesti (H&amp;Y 1) u odnosu na zdrave, dok su razlike postajale izraženije kako je bolest bila u odmaklijim stadijumima (H&amp;Y 2 I H&amp;Y 3). U grupi zdravih starost ispitanika korelirala je sa varijabilitetom koraka jedino u uslovima dvostrukog zadatka. Kod obolelih ova povezanost je uočena i pri hodu bez zadatka, a povezanost je bila jača u uslovima dvostrukog zadatka. Starost ispitanika i težina motornih znakova na UPDRS III korelirali su sa parametrima hoda kod obolelih od PB. Skorovi apatije i depresivnosti korelirali su sa promenama parametara hoda kod obolelih, s tim &scaron;to je apatija bila prisutna već u najranijim, a depresija tek u kasnijim stadijumima bolesti. Niža postignuća na testovima egzekutivnih funkcija povezana su sa pogor&scaron;anjem svih parametara hoda. Sa pogor&scaron;anjem parametara hoda tokom trajanja bolesti koreliraju i niža postignuća na testovima jezičkih i vidno- prostornih funkcija, kao i deficit pamćenja. Veličina hiperehogenosti korelira sa CV svih parametara hoda. Zaključak: Kod obolelih od Parkinsonove bolesti značajno se razlikuju vremenski i prostorni parametri hoda u poređenju sa zdravim, pre svega oni kojima se opisuje varijabilitet koraka. Ovi parametri su izraženiji kada se tokom hoda obavlja i dodatni kognitivni zadatak. Kada se tokom hoda obavlja motorni ili kombinovani motorni i kognitivni zadatak, pored varijabiliteta koraka javlja se i značajno produžen DS koji ukazuje na poremećaj ravnoteže. Na parametre hoda utiču starost ispitanika, težina i stadijum Parkinsonove bolesti. Apatija i depresija takođe značajno utiču na parametre hoda kod obolelih. Apatija se javlja u najranijim, a depresivnost tek u kasnijim stadijumima bolesti, &scaron;to govori u prilog stanovi&scaron;ta da je apatija zaseban simptom bolesti povezan sa dopaminergičkom disfunkcijom. Pogor&scaron;anja parametara hoda koreliraju sa o&scaron;tećenjem kognitivnih funkcija, pre svega egzekutivnih. U odmaklim stadijumima bolesti sa pogor&scaron;anjem hoda povezana su i lo&scaron;ija postignuća na testovima vidno-prostornih funkcija i pamćenja. Hiperehogenost substantia nigra na transkranijalnom parenhimskom ultrazvuku, koja se značajno če&scaron;će javlja i značajno je veće povr&scaron;ine kod obolelih u odnosu na zdrave, korelira sa varijabilitetom koraka.</p> / <p>Objectives: The aim of the study was to assess the contribution of clinical presentation, behavioral symptoms and cognitive functioning to gait characteristics in Parkinson&rsquo;s disease (PD). Hyperechogenicity of the substantia nigra on transcranial parenchimal ultrasound and its correlations with gait characteristics was also analyzed. Material and Methods: The experimental group consisted of 60 patients suffering from Parkinson&rsquo;s disease (22 women and 38 men, disease duration 5.06&plusmn;4.54, Unified Parkinson&#39;s Disease Rating Scale (UPDRS) total 39.76&plusmn;36.65, and UPDRS III 24.28&plusmn;15.18), who were classified into three subgroups according to the Hoehn and Yahr (H&amp;Y) stage of the disease: H&amp;Y 1, H&amp;Y 2 and H&amp;Y 3, with each subgroup containing 20 patients. The control group included 35 healthy subjects (19 women and 16 men) who were matched for years of age (64.21&plusmn;6.92 years PD vs 63.45&plusmn;7.75 healthy; p= .832) and formal education (12.63&plusmn;3.16 years PD vs 12.57&plusmn;2.87 healthy, p= .954). The subjects with MMSE&lt;24 were concerned demented and excluded from further analysis. The disease severity was assessed by the UPDRS, motor part (UPDRS III). Addenbrooke&rsquo;s Cognitive Examination-Revised (ACE-R) was used in assessment of global cognition, while executive functions were examined by Frontal Assessment Battery (FAB) and Executive Interview (EXIT-25) Hamilton&rsquo;s Depression Rating Scale (HAM-D) and Beck&rsquo;s Depression Inventory (BDI II) were used to screen for symptoms of depression, and the Apathy Scale (AS) and Hamilton&rsquo;s Anxiety Rating Scale (HAM- A) were used to assess apathy and anxiety. The measurements of spatial and temporal parameters of gait were performed using the GAITRite system, during the &ldquo;on&rdquo; state. The following eight parameters were analyzed: Cycle Time (CT), Stride Length (SL), Swing Time (ST) and Double Support Time (DS), as well as their coefficients of variation (CV). The impact of dual task on gait parameters was also observed. The subjects were asked to walk and simultaneously perform cognitive task (subtracting -7), then motor task (carrying a glass of water) and eventually combined task (subtracting and carrying a glass of water), while walking on the GAITRite electronic pathway. Transcranial parenchymal ultrasound was used to measure hyperechogenicity of substantia nigra. Results: Compared to healthy controls, PD patients had significantly higher gait variability during gait without additional tasks (decreased SL, increased CVSL and CVCT; p&lt; .05), whereas with a cognitive task the variability was even higher. During the motor task DS and CVDS were significantly increased as well, implying gait instability. A combined task had similar effects as the motor task, affecting all parameters. When the experimental group was divided into subgroups, variability of gait (SL, VCSL, CVCTandCVST) was minor in subgroup H&amp;Y 1, but more pronounced in later stages (H&amp;Y 2 and H&amp;Y 3). The age correlated with gait variability (CVCT and CVSL) only during the dual task in healthy subjects, whereas in PD patients the association was significant during normal gait and increased on the dual task. The age and severity of the disease on the UPDRS III also correlated with gait parameters. Apathy and depression were also associated with gait variability. Symptoms of apathy were significant in the earliest stages (H&amp;Y 1), whereas depression was notable in the later stages (H&amp;Y 3). Worse scores on tests of executive functions correlated with impairment of gait parameters. The impact of diminished language, visuo-spatial and memory functions on gait was also significant. Hyperechogenicity of the substantia nigra on transcranial parenchymal ultrasound occurred more frequently and was larger in PD patients and correlated well with gait variability. Conclusion: There is a significant impairment of temporal and spatial gait parameters in PD patients compared to healthy subjects, particularly the parameters of gait variability. These parameters become even more impaired during a simultaneous cognitive task. When a motor or combined task is performed, there is additional increase of DS, implying impairment of stability. Also, age and disease severity affect gait in PD patients. Apathy is significant in early stages (H&amp;Y 1) and depression in later stages (H&amp;Y 3), the finding which may be explained by the dopaminergic origin of apathy. Impairment of cognitive functions, most importantly executive dysfunction, are also associated with gait variability. Lower scores at visuo-spatial, language and memory tests are associated with worsened gait parameters of gait in later stages of PD. Finally, hyperechogenicity of the substantia nigra on transcranial parenchymal sonography, which occurs more frequently and is larger in PD patients, correlates with gait variability.</p>

Made available in DSpace on 2014-12-17T15:16:21Z (GMT). No. of bitstreams: 1 LorennaMMS_DISSERT.pdf: 2596311 bytes, checksum: 93aade0bed81a85e048ee273d698ce3a (MD5) Previous issue date: 2013-12-16 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / A pr?tica mental (PM) ? um m?todo que vem mostrando benef?cios na reabilita??o de pacientes neurol?gicos, por?m, ainda n?o h? evid?ncias dos efeitos imediatos na marcha de indiv?duos com Doen?a de Parkinson (DP). OBJETIVO: Verificar os efeitos imediatos da PM na marcha de indiv?duos com DP. M?TODO: Foi realizado um ensaio cl?nico com 20 indiv?duos com DP Idiop?tica, com idade m?dia de 61,35 anos (DP=?9,26). A avalia??o compreendeu os aspectos sociodemogr?ficos, cl?nicos e antropom?tricos, o estado cognitivo, o n?vel de incapacidade f?sica, o n?vel de capacidade de deambula??o, a nitidez da imagem mental, a cinem?tica da marcha, a fun??o motora, as atividades de vida di?ria e a mobilidade. Os indiv?duos foram distribu?dos aleatoriamente em 2 grupos: 10 para o grupo experimental (GE) e 10 para o grupo controle (GC). As interven??es foram realizadas em uma ?nica sess?o. Inicialmente, ambos os grupos precisaram identificar as altera??es t?picas da marcha parkinsoniana e memorizar as etapas da marcha normal. Em seguida, o GE foi submetido a um protocolo de PM e pr?tica f?sica (PF) da marcha e o GC ? PF da marcha. Foram reavaliados 10 minutos, 1 dia e 7 dias ap?s o fim da sess?o ?nica. Os desfechos prim?rios foram comprimento da passada e tempo total do apoio e balan?o e os secund?rios foram amplitude de movimento do quadril, velocidade e desempenho no TUG Test. A normalidade na distribui??o dos dados foi verificada por meio do teste Shapiro Wilk. O Teste t e o Mann-Whitney foram usados para verificar a homogeneidade dos grupos no baseline. Uma ANOVA para medidas repetidas verificou a intera??o entre os grupos nos momentos observados. A Correla??o de Pearson verificou a correla??o entre vari?veis. RESULTADOS: N?o houve diferen?a significativa entre os grupos. Foi observado diferen?a apenas intragrupo com rela??o a velocidade, comprimento da passada, amplitude de movimento do quadril, desempenho no TUG Test, tempo total do apoio e do balan?o. CONCLUS?O: A PM n?o mostrou efeitos superiores ? PF na marcha de indiv?duos com DPI, sendo realizada em uma ?nica sess?o

Indiana University-Purdue University Indianapolis (IUPUI) / The life expectancy of humans in today's era have increased to a very large extent due to the advancement of medical science and technology. The research in medical science has largely been focused towards developing methods and medicines to cure a patient after a diagnosis of an ailment. It is crucial to maintain the quality of life and health of the patient. It is of most importance to provide a healthy life to the elderly as this particular demographic is the most severely affected by health issues, which make them vulnerable to accidents, thus lowering their independence and quality of life. Due to the old age, most of the people become weak and inefficient in carrying their weight, this increases the probability of falling when moving around. This research of iterative nature focuses on developing a device which works as a preventive measure to reduce the damage due to a fall. The research critically evaluates the best approach for the design of the Pre-Fall detection system. In this work, we develop two wearable Pre-Fall detection system with reduced hardware and practical design. One which provides the capability of logging the data on an SD card in CSV format so that the data can be analyzed, and second, capability to connect to the Internet through Wifi. In this work, data from multiple accelerometers attached at different locations of the body are analyzed in Matlab to find the optimum number of sensors and the best suitable position on the body that gives the optimum result. In this work, a strict set of considerations are followed to develop a flexible, practical and robust prototype which can be augmented with different sensors without changing the fundamental design in order to further advance the research. The performance of the system to distinguish between fall and non-fall is improved by selecting and developing the most suitable way of calculating the body orientation. The different ways of calculating the orientation of the body are scrutinized and realized to compare the performance using the hardware. To reduce the number of false positives, the system considers the magnitude and the orientation to make a decision.

The objective of this study is to evaluate the effectiveness of opened and closed loop cueing intervention on Parkinson disease patients gait function focusing on the temporal and spatial parameters of gait and to define the most effective cueing approach for different gait parameters and finally to examine the closed loop feedback system for regular usage in regular physiotherapy clinics or patients own homes. A 37 clinical trial including 1014 patients were investigated to reach an answer for this review questions. Results reveled that both open and closed cueing intervention has a positive effect on gait spatial, temporal gait parameters and capable to reduce the number of freezes in Parkinson diseases patients. Auditory cueing strategies had a superior effect on patient speed of gait with higher rhythm of cues and better overall gait function during dual tasking. Visual cues showed better effect on stride length and stride frequency. The close loop feedback system of cues still built on complex machinery segments which make it difficult to be used as regular intervention in physiotherapy clinics and patients own homes. As an overall cueing intervention found to be significantly effective as locomotive therapeutic approach on gait functionality, but each intervention procedure and methodology...

Les troubles de la marche et le freezing entraînent une invalidité sévère et ont un impact important sur la qualité de vie des patients souffrant de la maladie de Parkinson (MP). Ceci est d'autant plus vrai que ces troubles répondent mal aux traitements actuels, médicamenteux et chirurgicaux. Leurs mécanismes physiopathologiques sont largement incompris. Toutefois, leur résistance aux traitements courants suggère l'extension du processus lésionnel vers des structures non-dopaminergiques concourant au contrôle de la locomotion. L'implication du noyau pédonculopontin (PPN) a été évoquée. L'objectif de cette étude était de mieux comprendre les circuits neuronaux impliqués dans ces troubles, ainsi que leur modulation par les médicaments dopaminergiques et la stimulation du PPN. Les contraintes d'immobilité de la tête, liées à l'utilisation de la technique de tomographie par émission de positons (TEP), excluant la réalisation d'une épreuve effective de marche, la tâche a été effectuée en imagerie mentale. Les mêmes réseaux neuronaux sont en effet activés lors de la réalisation effective et la représentation mentale d'un mouvement, sous réserve que l'imagerie mentale motrice soit réalisée selon une perspective dite kinesthésique. Il était donc nécessaire, au préalable, de vérifier l'aptitude des patients à imager leur marche selon cette modalité. Nos données vont dans ce sens, et montrent qu'il est possible d'améliorer cette capacité à travers une préparation spécifique. De plus, l'utilisation d'un protocole comportemental d'imagerie mentale reposant sur la loi de Fitts a permis de familiariser les patients avec la tâche d'imagerie mentale en amont de la réalisation des examens TEP, mais aussi de vérifier leur engagement dans cette dernière durant les acquisitions cérébrales. Les résultats obtenus à l'issue de l'étude menée en imagerie cérébrale confirment la complexité de la physiopathologie des troubles locomoteurs, et suggèrent notamment différents niveaux d'atteinte, à l'étage cortical, sous cortical, et du tronc cérébral, selon la nature dopa-sensible ou dopa-résistante du trouble concerné. En particulier, la dérégulation frontale semble confirmée. De plus, un dysfonctionnement du tronc cérébral pourrait être lié à l'émergence des troubles de la marche et du freezing. Nous avons également constaté une implication pariétale, mais son rôle compensateur, ou pathologique, reste encore à définir. Le freezing dopa-sensible pourrait en partie refléter l'expression aggravée de la bradykinésie parkinsonienne, étant donné l'efficacité de la lévodopa sur ce symptôme. La stimulation de la région des PPN semble quant à elle restaurer une boucle cortico-cérebello-thalamo-corticale, facilitant le mouvement dans le cas des troubles dopa-résistants. Des investigations complémentaires, sur un échantillon plus large de patients, sont donc nécessaires pour approfondir ces résultats. Une meilleure compréhension de la physiopathologie de ces troubles est en effet indispensable pour le développement de nouvelles thérapeutiques dans le but d'améliorer la prise en charge des patients souffrant de ces troubles invalidants, et ainsi leurs répercussions en termes de santé publique. / Gait disorders, including freezing of gait are frequent and disabling symptoms that lead to severe decrease of the quality of life on patients from Parkinson's disease (PD). This is emphasized by the fact that those difficulties respond poorly to current medical and surgical treatments. The underlying pathophysiology remains largely unknown. However, the resistance to actual treatments suggests the extension of the degenerative process towards non-dopaminergic structures. Involvement of the pedonculopontine nucleus (PPN) has been proposed. The aim of the study was to better understand the neural networks involved in those troubles, as well as their modulation by dopaminergic drugs and PPN stimulation. The constraints related to stillness of the head during Positron Emission Tomography (PET) exclude, necessarily, the realization of an effective gait. This task has been accomplished using mental moor imagery. The same mural networks are, indeed, activated during the actual execution and the mental representation of movement, under the assumption that motor mental imaging is undertaken from a kinesthetic perspective. Thus, it was necessary, preliminarily to this study, to control the ability of patients to imagine themselves walking from a kinesthetic point of view. Our data validate this condition. Moreover, they show that it is possible to improve this ability through a specific training. What is more, the use of a behavioral protocol, based on Fitt's law, helped the patients to familiarize themselves with this approach, before PET acquisitions, but also to control their correct performance during PET scan. The results, which have been obtained in cerebral imaging confirm the complexity of the underlying mechanisms of gait disorders, and suggest notably different levels of deregulation, on a cortical, sub-cortical and brainstem. In particular, frontal deregulation appears to be confirmed. Moreover, a deregulation of the brainstem could be more particularly involved in gait disorders apparition. We have also evidenced parietal implication, but its exact compensatory or pathologic role remains to be determined. Levodopa-responsive freezing seems to be a consequence of worsened parkinsonian bradykinesia. PPN stimulation seems able to restore a functional cortico-cerebello-cortical loop, facilitating movement. Complementarily studies, on a larger selection of patients, are thus necessary to complete those results. A better understanding of pathophysiology is, as a matter of fact, necessary for the development of new therapeutics in order to improve the therapy of patients from those very invalidating troubles, and thus, to reduce their impact on public health.