Estimation des efforts des muscles de la cheville et de la hanche lors de la génération d'énergie à la marche chez le sujet sain

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

Évaluation de la force et de l'endurance des muscles para-vertébraux chez des femmes et des hommes : étude comparative de différents tests dynamométriques

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

Activité EMG des muscles du dos chez des patients dystrophiques

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

Imagerie des muscles du membre supérieur et du dos

Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.

Fonction et structure des muscles du plancher pelvien de femmes traitées par chirurgie et radiothérapie à la suite d'un cancer de l'endomètre

Ce mémoire porte sur les propriétés fonctionnelles du plancher pelvien à la suite de traitements pour un cancer de l’endomètre. Chez les femmes, le cancer de l’endomètre est le cancer gynécologique ayant la plus forte prévalence. Les traitements oncologiques de ce cancer ont des conséquences néfastes sur la continence urinaire et il est possible que des altérations aux muscles du plancher pelvien à la suite de ces traitements puissent expliquer en partie cette problématique. Ce mémoire est composé de deux études principales. La première étude porte sur la recension des écrits liés aux impacts de la radiothérapie sur la structure anatomique et la fonction musculaire du plancher pelvien chez des adultes atteints d’un cancer pelvien. La deuxième étude compare les propriétés fonctionnelles du plancher pelvien de femmes avec incontinence urinaire à la suite d’un cancer de l’endomètre traité par chirurgie et une radiothérapie adjuvante (groupe à l’étude), à celles de femmes avec hystérectomie sans incontinence (groupe témoin). Cette étude a permis de mettre en évidence une diminution de l’ouverture maximale à l’entrée vaginale, de la longueur vaginale, de la force maximale volontaire du plancher pelvien, du taux de développement de la force dans un test de force maximale et de la coordination lors d’un test de contractions rapides. Ainsi, les deux études de ce mémoire apportent de nouvelles évidences sur les altérations des propriétés fonctionnelles du plancher pelvien à la suite de traitements pour un cancer génital.

Contrôle cortical et postural des muscles multifides : Influence de la lombalgie chronique, des exercices et de la neurostimulation périphérique

La lombalgie chronique (LC) représente de nos jours un fardeau individuel et sociétal énorme. Le contrôle du tronc est complexe, il dépend de l’intégration des afférences périphériques et de l’interaction des régions cérébrales impliquées dans la matrice de la douleur. Les individus souffrant de lombalgie présentent des désordres de contrôle moteur de la colonne vertébrale et une modification de la plasticité du cerveau. Ces altérations semblent réversibles et peuvent être améliorées par différents exercices prescrits en physiothérapie. Par contre, même si les exercices diminuent la douleur, l’effet n’en demeure pas moins modeste. L’utilisation de la neurostimulation magnétique périphérique (rPMS) qui génère des informations sensorielles (entre autres proprioceptives cohérentes avec le contrôle des muscles) et qui agit donc sur l’excitabilité cérébrale et les mécanismes de plasticité pourrait potentialiser les gains atteints grâce aux exercices. L’objectif principal de la thèse est de mieux comprendre le contrôle cortical et postural des muscles du tronc, l’influence de la lombalgie chronique, des exercices et de de la neurostimulation périphérique. La série d’études proposée dans la thèse vise à (i) comprendre les changements présents au niveau du contrôle cortico-moteur des muscles multifides et des ajustements posturaux anticipatoires en lombalgie chronique (étude 1) ainsi que l’influence du côté de la douleur lombaire (étude 2); (ii) déterminer quel type d’exercice utilisé en physiothérapie (global ou isométrique) influence la plasticité corticale (étude 3) et; (iii) déterminer si l’ajout de rPMS potentialise ces effets (étude 4). Les données présentées dans la thèse confirment que les individus avec LC présentent des différences dans le fonctionnement du cortex moteur primaire par rapport aux individus en santé. De plus, le côté de la douleur semble influencer différemment l’excitabilité de base du M1. Enfin, nous avons démontré que l’exercice isométrique agissait de façon spécifique sur la plasticité du M1, ainsi que sur les ajustements posturaux anticipatoires, et que l’ajout des rPMS à l’exercice diminue immédiatement la douleur et modifie le contrôle des muscles multifides. D’autres études sont nécessaires pour confirmer le bénéfice des rPMS chez des populations souffrant de douleur chronique et pour un éventuel transfert clinique.

Correlação entre o sinal mecanomiográfico e a escala modificada de Ashworth durante avaliação clínica da espasticidade

Spasticity is a common disorder in people who have upper motor neuron injury. The involvement may occur at different levels. The Modified Ashworth Scale (MAS) is the most used method to measure involvement levels. But it corresponds to a subjective evaluation. Mechanomyography (MMG) is an objective technique that quantifies the muscle vibration during the contraction and stretching events. So, it may assess the level of spasticity accurately. This study aimed to investigate the correlation between spasticity levels determined by MAS with MMG signal in spastic and not spastic muscles. In the experimental protocol, we evaluated 34 members of 22 volunteers, of both genders, with a mean age of 39.91 ± 13.77 years. We evaluated the levels of spasticity by MAS in flexor and extensor muscle groups of the knee and/or elbow, where one muscle group was the agonist and one antagonist. Simultaneously the assessment by the MAS, caught up the MMG signals. We used a custom MMG equipment to register and record the signals, configured in LabView platform. Using the MatLab computer program, it was processed the MMG signals in the time domain (median energy) and spectral domain (median frequency) for the three motion axes: X (transversal), Y (longitudinal) and Z (perpendicular). For bandwidth delimitation, we used a 3rd order Butterworth filter, acting in the range of 5-50 Hz. Statistical tests as Spearman's correlation coefficient, Kruskal-Wallis test and linear correlation test were applied. As results in the time domain, the Kruskal-Wallis test showed differences in median energy (MMGME) between MAS groups. The linear correlation test showed high linear correlation between MAS and MMGME for the agonist muscle as well as for the antagonist group. The largest linear correlation occurred between the MAS and MMG ME for the Z axis of the agonist muscle group (R2 = 0.9557) and the lowest correlation occurred in the X axis, for the antagonist muscle group (R2 = 0.8862). The Spearman correlation test also confirmed high correlation for all axes in the time domain analysis. In the spectral domain, the analysis showed an increase in the median frequency (MMGMF) in MAS’ greater levels. The highest correlation coefficient between MAS and MMGMF signal occurred in the Z axis for the agonist muscle group (R2 = 0.4883), and the lowest value occurred on the Y axis for the antagonist group (R2 = 0.1657). By means of the Spearman correlation test, the highest correlation occurred between the Y axis of the agonist group (0.6951; p <0.001) and the lowest value on the X axis of the antagonist group (0.3592; p <0.001). We conclude that there was a significantly high correlation between the MMGME and MAS in both muscle groups. Also between MMG and MAS occurred a significant correlation, however moderate for the agonist group, and low for the antagonist group. So, the MMGME proved to be more an appropriate descriptor to correlate with the degree of spasticity defined by the MAS.

Variable Recruitment in Bundles of Miniature Pneumatic Artificial Muscles and Space Qualified Pneumatic Artificial Muscles

The natural compliance and force generation properties of pneumatic artificial muscles (PAMs) allow them to operate like human muscles in anthropomorphic robotic manipulators. Traditionally, manipulators use a single PAM or multiple PAMs actuated in unison in place of a human muscle. However, these manipulators experience efficiency losses when operated outside their target performance ranges. The unidirectional actuation behavior of a miniature PAM bundle and bidirectional actuation behavior of an antagonistic pair of miniature PAM bundles are characterized and modeled. The results are used to motivate the application of a variable recruitment control strategy to a parallel bundle of miniature PAMs as an attempt to mimic the selective recruitment of motor units in a human muscle to improve the operating efficiency of the actuator. Additionally, the fabrication and quasi-static testing results for PAMs assembled from candidate space qualified bladder and braided sleeve materials for use in space robotics are assessed.

Botulinum toxin in masticatory muscles of the adult rat induces bone loss at the condyle and alveolar regions of the mandible associated with a bone proliferation at a muscle enthesis

International audience

Comparação de diferentes tipos de exercício na composição corporal e força em jovens desportistas do sexo feminino

O estudo pretende comparar o efeito de diferentes tipos de exercício físico na composição corporal e força em jovens desportistas do sexo feminino. A amostra foi constituída por vinte e seis desportistas femininas com idades compreendidas entre os 16 e 21 anos. Previamente ao início do estudo foram sujeitas ao 1º momento de avaliação, e após vinte e quatro semanas realizaram o segundo e ultimo momento de avaliação. Os parâmetros avaliados foram a composição corporal através da técnica de absorciometria radiológica de dupla energia; a força isocinética, nomeadamente os momentos de força (peak-torques) e rácios nos músculos extensores e flexores do joelho; a potência muscular nos membros inferiores através dos saltos verticais Squat jump e Countermovement jump. Posteriormente foram separadas em quatro grupos, grupo natação e exercício vibratório (NAT EV; n= 6), grupo natação (NAT; n=6), grupo futsal (FUTS; n= 6) e o grupo de controlo (CONT; n= 8). O grupo (NAT/EV), participou num programa de exercício vibratório (EV), três sessões por semana complementar ao treino de natação. O grupo de (NAT) cumpriu o plano de treino correspondente à disciplina, o grupo de (FUTS) cumpriu o treino referente à respetiva modalidade, o grupo controlo (CONT) realizou somente os exercícios físicos inerentes às aulas de educação física na escola. Resultados: Nas comparações inter grupos, verificou-se no grupo FUTS um aumento de 0,1 (g/m2) ± 0,0 nos valores da DMO-PE, quando comparado com o grupo de CONT, nas comparações intra grupo o grupo de NAT EV registou um acréscimo de 0,1 (g/m2) ± 0,1 nos valores da DMO-TC. Em conclusão, os resultados obtidos sugerem que a modalidade de FUTS promoveu mais alterações na composição corporal, nomeadamente na DMO-PE, no entanto dados conseguidos pelo grupo de NAT EV sugerem que o exercício vibratório poderá influenciar positivamente o incremento da DMO; ABSTRACT: The objective of this study was to compare the effect of different types of exercise on body composition and strength in young female athletes. The sample consisted of twenty-six female athletes aged between 16 and 21. Before the study there was a 1st evaluation point, after twenty-four weeks there was the 2nd and final evaluation. We evaluated body composition through x-ray absorptiometry technique of dual energy, isokinetic strength, including the peak-torques and ratios in the extensor and flexor muscles of the knee; the muscle power in the lower limbs was evaluatated through the vertical jumps Squat jump and countermovement jump. During the study they were separated into four groups, swimming exercise group and vibration (NAT EV; n = 6), swimming group (NAT; n= 6), footsal group (FUTS; n= 6) and control group (CONT; n= 8). The NAT/EV group, participated in a vibrating exercise program (EV), complementary to swimming training, with three sessions per week. The NAT group fulfilled the corresponding swimming workout plan, FUTS group fulfilled the training related to futsal, the CONT group only performed the usual exercises in physical education classes at school. Results: In intergroup comparisons, there was an increase in FUTS group of 0.1 (g / m2) ± 0.0 in the values of MBD-PE, when compared with the CONT group comparisons in intra-group group NAT EV increased by 0.1 (g / m2) ± 0.1 in BMD-TC values. In conclusion, the results suggest that FUTS group promoted more changes in body composition, particularly in BMD-PE, but data obtained by NAT EV group suggest that vibration exercise can positively influence the increase in BMD.

Effects of radiation therapy on the structure and function of the pelvic floor muscles of patients with cancer in the pelvic area : a systematic review

Purpose Radiation therapy (RT) is often recommended in the treatment of pelvic cancers. Following RT, a high prevalence of pelvic floor dysfunctions (urinary incontinence, dyspareunia, and fecal incontinence) is reported. However, changes in pelvic floor muscles (PFMs) after RT remain unclear. The purpose of this review was to systematically document the effects of RT on the PFM structure and function in patients with cancer in the pelvic area. Methods An electronic literature search using Pubmed Central, CINAHL, Embase, and SCOPUS was performed from date of inception up to June 2014. The following keywords were used: radiotherapy, muscle tissue, and pelvic floor. Two reviewers selected the studies in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses Statement (PRISMA). Out of the 369 articles screened, 13 met all eligibility criteria. The methodological quality was assessed using the QualSyst scoring system, and standardized mean differences were calculated. Results Thirteen studies fulfilled all inclusion criteria, from which four were of good methodological quality. One presented strong evidence that RT affects PFM structure in men treated for prostate cancer. Four presented high-level evidence that RT affects PFM function in patients treated for rectal cancer. Meta-analysis was not possible due to heterogeneity and lack of descriptive statistics. Conclusion There is some evidence that RT has detrimental impacts on both PFMs’ structure and function. Implications for cancer survivors A better understanding of muscle damage and dysfunction following RT treatment will improve pelvic floor rehabilitation and, potentially, prevention of its detrimental impacts.

Pelvic floor muscles training to reduce symptoms and signs of vulvovaginal atrophy : a case study

Objective: Vulvovaginal atrophy (VVA), caused by decreased levels of estrogen, is a common problem in aging women. Main symptoms of VVA are vaginal dryness and dyspareunia. First-line treatment consists of the application of local estrogen therapy (ET) or vaginal moisturizer. In some cases however, symptoms and signs persist despite those interventions. This case study describes a 77-year-old woman with severe VVA symptoms despite use of local ET and the addition of pelvic floor muscle (PFM) training to her treatment. Methods: A patient with stress urinary incontinence and VVA was referred to a randomized clinical trial on PFM training. On pretreatment evaluation while on local ET, she showed VVA symptoms on the ICIQ Vaginal Symptoms questionnaire and the ICIQ-Female Sexual Matters associated with lower urinary tract Symptoms questionnaire, and also showed VVA signs during the physical and dynamometric evaluation of the PFM. She was treated with a 12-week PFM training program. Results: The patient reported a reduction in vaginal dryness and dyspareunia symptoms, as well as a better quality of sexual life after 12 weeks of PFM training. On posttreatment physical evaluation, the PFMs' tone and elasticity were improved, although some other VVA signs remained unchanged. Conclusions: Pelvic floor muscle training may improve some VVA symptoms and signs in women taking local ET. Further study is needed to investigate and confirm the present case findings and to explore mechanisms of action of this intervention for VVA.

Effects of radiation therapy on the structure and function of the pelvic floor muscles of patients with cancer in the pelvic area : a systematic review

Purpose Radiation therapy (RT) is often recommended in the treatment of pelvic cancers. Following RT, a high prevalence of pelvic floor dysfunctions (urinary incontinence, dyspareunia, and fecal incontinence) is reported. However, changes in pelvic floor muscles (PFMs) after RT remain unclear. The purpose of this review was to systematically document the effects of RT on the PFM structure and function in patients with cancer in the pelvic area. Methods An electronic literature search using Pubmed Central, CINAHL, Embase, and SCOPUS was performed from date of inception up to June 2014. The following keywords were used: radiotherapy, muscle tissue, and pelvic floor. Two reviewers selected the studies in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses Statement (PRISMA). Out of the 369 articles screened, 13 met all eligibility criteria. The methodological quality was assessed using the QualSyst scoring system, and standardized mean differences were calculated. Results Thirteen studies fulfilled all inclusion criteria, from which four were of good methodological quality. One presented strong evidence that RT affects PFM structure in men treated for prostate cancer. Four presented high-level evidence that RT affects PFM function in patients treated for rectal cancer. Meta-analysis was not possible due to heterogeneity and lack of descriptive statistics. Conclusion There is some evidence that RT has detrimental impacts on both PFMs’ structure and function. Implications for cancer survivors A better understanding of muscle damage and dysfunction following RT treatment will improve pelvic floor rehabilitation and, potentially, prevention of its detrimental impacts.

Pelvic floor muscles training to reduce symptoms and signs of vulvovaginal atrophy : a case study

Objective: Vulvovaginal atrophy (VVA), caused by decreased levels of estrogen, is a common problem in aging women. Main symptoms of VVA are vaginal dryness and dyspareunia. First-line treatment consists of the application of local estrogen therapy (ET) or vaginal moisturizer. In some cases however, symptoms and signs persist despite those interventions. This case study describes a 77-year-old woman with severe VVA symptoms despite use of local ET and the addition of pelvic floor muscle (PFM) training to her treatment. Methods: A patient with stress urinary incontinence and VVA was referred to a randomized clinical trial on PFM training. On pretreatment evaluation while on local ET, she showed VVA symptoms on the ICIQ Vaginal Symptoms questionnaire and the ICIQ-Female Sexual Matters associated with lower urinary tract Symptoms questionnaire, and also showed VVA signs during the physical and dynamometric evaluation of the PFM. She was treated with a 12-week PFM training program. Results: The patient reported a reduction in vaginal dryness and dyspareunia symptoms, as well as a better quality of sexual life after 12 weeks of PFM training. On posttreatment physical evaluation, the PFMs' tone and elasticity were improved, although some other VVA signs remained unchanged. Conclusions: Pelvic floor muscle training may improve some VVA symptoms and signs in women taking local ET. Further study is needed to investigate and confirm the present case findings and to explore mechanisms of action of this intervention for VVA.

Long term betaine supplementation regulates genes involved in lipid and cholesterol metabolism of two muscles from an obese pig breed

This study evaluates the effects of betaine supplementation (1 g kg−1 for 20 weeks) on the regulation of genes involved in lipid and cholesterol metabolism of Longissimus lumborum and Biceps femoris from obese Alentejano pigs. Betaine supplementation led to an increase in total cholesterol in both muscles, complementing results previously published indicating a significant increase on the intramuscular lipid content. The expression of twelve genes involved in lipogenesis, lipolysis/FA oxidation, FA transport, and cholesterol metabolism, as well as two transcription factors were also evaluated. Genes related to lipid and cholesterol synthesis plus FA transport were consistently up-regulated in both muscles of betaine fed pigs. On the other hand, genes related to lipolysis/FA oxidation were not affected or down-regulated by betaine supplementation. Our data suggest that the underlying mechanism regulating IMF and cholesterol accumulation in Alentejano pigs supplemented with betaine is associated with the up-regulation of genes involved in lipid synthesis, FA transport, and cholesterol synthesis.