A entorse de tornozelo pode ocorrer pela amplitude exagerada de inversão e flexão plantar. Lacuna importante no controle postural é a ação do ajuste postural antecipatório (APA) e compensatório (APC) para estabilizar a articulação do tornozelo. O reflexo de estiramento (M1) e as reações pré-programadas (M2 e M3) foram pouco exploradas em pessoas com instabilidade crônica de tornozelo (CAI). A co-ativação e inibição são fenômenos modulados em nível medular por neurônios excitatórios e inibitórios, mas as informações sobre esses fenômenos atuam na CAI são escassas. A fadiga muscular afeta negativamente as pessoas na condição de CAI. Logo, qual é a relação entre APA e APC no movimento de entorse de tornozelo? A CAI pode alterar as respostas M1, M2 e M3 por lesões osteomioarticulares do tornozelo? A fadiga pode alterar todas estas variáveis em pessoas com CAI? Esta dissertação de mestrado teve por objetivo geral analisar o sinal EMG no movimento simulado da inversão de tornozelo em atletas universitárias de futsal que possuem e que não possuem a CAI. A amostra foi composta por 24 atletas de futsal feminino universitário e foram divididos em dois grupos: controle e instabilidade. A simulação do movimento de entorse do tornozelo foi feita por meio de uma plataforma mecânica que simula o movimento de inversão de tornozelo. Foi utilizado um sistema de aquisição de sinais de 8 canais, onde foram utilizados 4 canais para registro EMG e 3 canais para o registro do sinal do acelerômetro. Para determinar o início e final do movimento da plataforma foi fixado um acelerômetro 3D em uma das bordas da plataforma de inversão. Foram realizar quedas aleatórias na plataforma de inversão antes e depois do protocolo de fadiga. Foram monitorados os músculos tibial anterior, fibular longo e curto e gastrocnêmio lateral. Os períodos analisados foram os APA, APC, reflexo de estiramento muscular e reações pré-programadas. Parece que durante os períodos M1, M2 e M3 há um fator de desproteção no grupo instabilidade, apesar de haver em alguns pares de músculos uma maior coerência, comparado com o grupo controle. Durante o APA os músculos eversores não foram alterados no grupo instabilidade, mas no APC os eversores foram menores comparados com o grupo controle, sugerindo um fator de desproteção. Na correlação cruzada, todos os pares de músculos foram maiores no grupo controle, uma forma de se opor ao movimento de inversão maior que o grupo instabilidade. A co-ativação e inibição recíproca foram alteradas com a fadiga, aumentando após a fadiga, mas a inibição recíproca foi maior somente no grupo controle, podendo mover a articulação do tornozelo de uma forma mais facilitada que o grupo instabilidade. A coerência de pares de músculos foi diferente somente nos grupos, sendo que durante o APC os músculos não sincronizaram de forma satisfatória no grupo instabilidade, somente durante APA e período M / Ankle sprain is an injury associated with sports and exercise and may be used for the exaggerated amplitude of inversion and plantar flexion. An important gap in postural control is the anticipatory (APA) and compensatory (CPA) postural adjustments to stabilize the ankle joint. The stretch reflex (M1) and the pre-programmed reactions (M2 and M3) were poorly explored in people with chronic ankle instability (CAI). Coactivation and recíprocal inhibition are phenomena modulated at the spinal level by excitatory and inhibitory neurons, but the information about these phenomena in CAI is scarce. Negative effects of muscular fatigue affect persons with CAI. Therefore, What is the relationship between APA and CPA in the movement of ankle sprain? Can CAI change the M1, M2 and M3 responses due to osteomyoarticular ankle injuries? Can fatigue change all these variables in people with CAI? This dissertation aimed at analysing the EMG signal in the simulated ankle inversion movement task in female indoor soccer university athletes who have and do not have the CAI. Participants were 24 female indoor soccer college athletes divided in two groups: control and instability. Simulation of ankle sprain was performed with a mechanical platform that simulated the ankle inversion movement. An 8-channel signal acquisition system was used, which 4 channels were used for EMG recording and 3 channels to record accelerometer signal. For determine the beginning and end of the movement of the inversion platform a 3D accelerometer was fixed to one of the edges of the inversion platform. We performed random falls on the inversion platform before and after the fatigue protocol. Muscles monitored were mm. tibialis anterior, fibularis longus, fibularis brevis and gastrocnemius lateralis. Data epochs were APA, CPA, muscle stretching reflex and preprogramed reactions. During M1, M2 and M3 epochs, there was an unprotection factor for instability group, although in some muscle pairs there were more coherence compared to control group. The eversor muscles were not changed in instability group compared with control group during APA epoch, it suggests an unprotect factor. All pair of muscles, the cross correlation were greater in control group to oppose the inversion movement greater in control group than instability group. Coactivation and reciprocal inhibition were changed with fatigue, increasing after fatigue, but reciprocal inhibition was greater only in control group, and could move the ankle joint more easily than for instability group. Coherence of muscle pairs was different only between groups, and during CPA the muscles did not synchronize satisfactorily for instability group, only during APA and M epochs

Orientadores: José Martins Filho, Roberto Teixeira Mendes / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-20T03:33:35Z (GMT). No. of bitstreams: 1 Serafim_RobertoMarsaioli_M.pdf: 846829 bytes, checksum: 43f38782b5683de6c685ada47b242bf7 (MD5) Previous issue date: 2011 / Resumo: O estudo foi desenhado para investigar a confiabilidade intraexaminador da medida da força muscular isométrica da musculatura inversora e eversora do tornozelo, utilizando o dinamômetro manual Lafayette, em voluntários jovens saudáveis. Vinte voluntários (18-21 anos de idade) foram submetidos a três avaliações consecutivas de força isométrica de ambos (direito e esquerdo) inversores e eversores de tornozelo, medidas em três ocasiões diferentes com 48hs de intervalo. Os voluntários eram saudáveis, sem história de lesão prévia de tornozelo ou déficit neuro muscular. As medidas foram realizadas com a solicitação de força máxima. Dados foram analisados comparando tanto a média de cada dia como o máximo do valor obtido em cada dia. A confiabilidade da medida foi avaliada calculando-se o Coeficiente de Correlação Intraclasse (ICC). Resultados: O ICC intraexaminador para força máxima na inversão do tornozelo direito e esquerdo foi 0.90 e 0.87, respectivamente. O ICC intraexaminador para força máxima na eversão do tornozelo direito e esquerdo variou de 0.79 a 0.86 e de 0.88 a 0.93, respectivamente. Resultados semelhantes foram obtidos comparando a média de valores para cada dia. Nossos resultados indicam que o uso do dinamômetro manual da marca Lafayette é confiável e pode ser útil para avaliar a extensão do déficit de força muscular nas lesões de tornozelo, assim como a evolução das medidas de força na evolução do tratamento / Abstract: The study was designed to investigate the intratester reliability of isometric ankle inversion- and eversion-strength measurement using Lafayette hand held dynamometer in healthy youngth. Twenty volunteers (18-21 years) were submitted to three consecutive evaluations of both (right and left) ankle inversion- and eversion-strength measurement in three different occasions (48h interval). The volunteers were considered healthy with no previous history of ankle lesion. The volunteers were asked to perform maximum strength in each measurement. Data were analyzed comparing either the mean of each day or the maximum value obtained in each day. Reliability of the measurement was assessed by calculating the intraclass correlation coefficient (ICC). Results: The intratester ICC for maximum strength in right and left ankle inversion was 0.90 and 0.87, respectively. The intratester ICC for maximum strength in right and left ankle eversion ranged from 0.79 to 0.86 and from 0.88 to 0.93, respectively. Similar results were obtained comparing the mean values for each day. Our results indicate that use of the Lafayette hand held dynamometer is reliable and may be useful for evaluating extension of muscle strength deficit in ankle lesions, as well the evolution of treatment / Mestrado / Pediatria / Mestre em Saude da Criança e do Adolescente

The human ankle joint is hypothesized to be a primary controller of support, propulsion and steering during locomotion. A series of experiments were initiated to understand ankle plantarflexor muscle kinematics and kinetics in normal and pathological gait, and to define the specific locomotor demands of community ambulation. Additional experiments were then conducted to quantify the effects of walking speed on plantar pressures and centre of mass motion, to illuminate the role of the ankle in acceleration and deceleration during walking, and to examine how humans alter their kinematics and kinetics to turn. The results of these experiments provide support for the hypothesis that the ankle joint is important in a wide range of locomotor movements beyond walking straight ahead at constant speed. The ankle appears instrumental in adapting to different walking speeds, altering both the pressures on specific regions the plantar surface and the motion of the centre of mass across a range of speeds. The ankle also has subtle kinetic changes that appear to modulate acceleration and deceleration during single limb stance. For turning, the ankle plays a role during slowing into the turn and accelerating after the turn, but mediolateral shears appear to alter the trajectory of the body to negotiate a corner and the external hip rotators appear to rotate the trunk toward the new direction of travel. This work extends our understanding of the ankle in functionally relevant gait activities beyond simple straight-ahead walking at constant speed. The published papers included in this supporting statement have been cited by 180 different subsequent peerreviewed publications, suggesting that this work has had some impact on the field.

Submitted in partial compliance with the requirements for the Master’s Degree in Technology: Chiropractic, Durban University of Technology, Durban, South Africa, 2017. / Background: Acute ankle sprains and chronic ankle instability syndrome (CAIS) may be managed effectively through conservative management approaches such as strapping. There are two main types of strapping viz. rigid tape which is used to stabilise the joint and limit joint motion and elastic tape which permits joint motion but provides dynamic support. Kinesio™ tape is becoming increasingly popular in the management of various conditions. It is reportedly beneficial in reducing pain, improving circulation, increasing proprioception and correcting muscle function. Due to claimed benefits of Kinesio™ tape, it should, in theory, be beneficial in the management of individuals with CAIS particularly in terms of reducing pain and improving proprioception. AIM: To investigate the effect of three types of strapping applied in the method described for the application of Kinesio™ tape in the management of CAIS. METHODS This study consisted of three groups of 15 participants (recruited through convenience sampling) with each group receiving a different tape (i.e. rigid, elastic or Kinesio™ tape), all three groups, however, received the same taping method which was the Kinesio™ tape functional correction application. After obtaining informed consent each participant underwent a case history, physical examination and a foot an ankle orthopaedic examination. Thereafter, baseline measurements of subjective pain rating (NRS-101), pain threshold (analogue algometer), ankle dorsiflexion, plantarflexion and inversion (analogue goniometer) and proprioception (Biodex Biosway portable balance system) were documented. Depending on the group, the particular tape was then applied and a follow up consultation was made for two to three days later where the tape was removed, measurements were reassessed and the tape was reapplied. At the final consultation three to four days later, the tape was removed and final measurements were assessed and documented. Statistical intra- (using Wilcoxon Signed Ranks Test) and inter-group (using the Mann-Whitney U-test) analyses of the data were performed due to a skewed distribution of the variables. Data was analysed using SPSS version 21.0 with the level of significance set at 0.05. RESULTS The mean (± SD) age of the participants was 24.8 (4.7) and there were 23 male participants in total. Intra-group analyses of subjective outcome measurements showed significant increases (p < 0.05) in subjective pain rating in all three groups across all consultations. Similarly, intra-group analyses of objective outcome measurements found significant increases (p < 0.05) in pain threshold and dorsiflexion range of motion in all three groups across all consultations. Plantarflexion and inversion range of motion also showed significant increases (p < 0.05) but these were not consistent across all consultations. Intra-group analyses of the sway index showed no significant improvements (p > 0.05) in Groups Two and Three across the three consultations. Only Group One showed significant increases during the eyes open foam surface (EOFoS) (p = 0.013) and eyes closed foam surface (ECFoS) (p = 0.047) test conditions between Consultations One and Two. Inter-group analyses of subjective outcome measurements showed no significant increases (p > 0.05) in subjective pain rating across each of the three consults in all three groups. Inter-group analyses of objective outcome measurements revealed a significant increase in pain threshold (p = 0.040) between Groups Two and Three at Consultation One. There was a significant increase in plantarflexion between Groups One and Three at Consultation Two (p = 0.021) and Consultation Three (p = 0.030). There were no other significant results amongst the three groups. CONCLUSION The results suggest that pain rating, pain threshold and ankle dorsiflexion would improve if taping is applied in the manner described for Kinesio™ tape irrespective of the type of taping used in the management of CAIS. The taping method did not result in a significant difference in proprioception. Further studies, with larger sample sizes are required to confirm the findings of this study and to determine the role of taping in the management of CAIS. / M

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Dissertation submitted in partial compliance with the requirements for the Master's Degree in Technology: Chiropractic, Technikon Natal, 1999. / To investigate the efficacy of adjusting the ankle in the treatment of subacute and chronic grade I and II ankle inversion sprains. The researcher hypothesised that adjusting a symptomatic ankle, in terms of the above, would result in a more significant improvement than that of a placebo treatment / M

Assistive technologies traditionally rely on either strong actuation or passive structures to provide users with increased strength, support or the ability to perform lost functions. At one end of the spectrum are powered exoskeletons, which significantly increase a user’s strength, but require strong actuators, complex control systems, and heavy power sources. At the other end are orthoses, which are generally unpowered and lightweight devices that rely on their structure’s mechanical behaviour to enhance user’s support and stability. Ideally, assistive technologies should achieve both systems’ characteristics by enhancing human motion abilities while remaining lightweight and efficient. This can be achieved by using distinctive actuators to harness gait energy, towards enhancing human mobility and performance. Pneumatic Artificial Muscles (PAMs), compliant and flexible, yet powerful and lightweight, present a unique set of characteristics compared to other mechanical actuators in human mobility applications. However, given the need of a compressor and power source, PAMs present a significant challenge, limiting their application. In contrast, PAMs can be implemented as unpowered actuators that act as non-linear elastic elements. This thesis aims to develop a wearable lightweight unpowered ankle exoskeleton, which relies on the PAM to harness gait energy and compliment the human ankle biomechanical abilities at the push off movement, thusly assisting the user in propelling the body forward during walking. Presently, limited PAM models have been developed to analyse PAM passive behaviour and to assist in designing and selecting the appropriate PAM for unpowered application. Thus, this thesis aims to develop a passive model for the PAM. To mechanically validate the proposed exoskeleton design, a prototype is fabricated, and tested within an Instron tensile machine setup. The unpowered exoskeleton has shown its ability to provide significant contribution to the ankle timed precisely to release at the push off phase of the gait cycle. Furthermore, the proposed PAM stiffness model is validated experimentally, and accounts for muscle pressure, geometry, material and stretching velocity. This enables the evaluation of the impact of various parameters on the muscle behaviour and designs the PAM accordingly for the unpowered ankle exoskeleton

The objective of the present study was to; 1) determine if the use of a continuous cognitive task demonstrates distinct characteristics of a more automatic control of posture, compared to an external focus (EF) and feet together (FT) postural task, and to 2) examine which condition, if any, exhibits the characteristics of increased ankle stiffness proposed by Winter et al. (1998), as well as displaying increased ankle muscular co-contractions, which are a suggested neuromuscular mechanism that stiffens posture. Fifteen young adults stood on a force platform and performed 4 separate conditions: FT, EF, single number sequence (SNS), and double number sequence (DNS). Throughout the session, surface electromyography (EMG) signals were collected from the tibialis anterior (TA) and medial gastrocnemius (MG) of each leg. Each testing session consisted of 24 trials, with 6 per condition. Results displayed decreased sway area for SNS and DNS compared to FT. Sway variability in the anterior/posterior (AP) direction SNS and DNS were smaller compared to EF and FT. As well sway variability in the medial/lateral (ML) direction was smaller for SNS and DNS compared to FT. ML Mean velocity (MV) did not differ across conditions, though in the AP direction it was larger for SNS and DNS compared to EF and FT. AP Mean power frequency (MPF) was larger for SNS compared to FT. In the ML direction MPF was larger for SNS and DNS compared to FT. Co-Contraction indices revealed no differences across conditions. Conversely the left TA for DNS revealed increased EMG activation compared to EF and SNS.

As doenças cerebrovasculares, incluindo o acidente vascular encefálico (AVE), são a segunda causa de morte no mundo, e o principal causador das incapacidades na população adulta. Devido à reorganização cortical, quanto mais precoce a reabilitação é realizada, melhores são os resultados. Desta forma, novos tratamentos e soluções tecnológicas foram desenvolvidos para enfrentar os desafios da reabilitação pós AVE, por exemplo, aumento da intensidade e duração da terapia incluindo manipulação externa, treinamento do movimento bilateral, e reabilitação robótica. Os dispositivos robóticos possibilitam a realização de tarefas específicas repetidas vezes, de forma controlada e confiável, fator determinante para a facilitação da reorganização cortical, com aumento da habilidade motora e melhora do desempenho das atividades funcionais. O objetivo principal deste trabalho foi verificar a adequação e usabilidade da Plataforma Robótica de Reabilitação de Tornozelo - PRRT em indivíduos que precisam de reabilitação de tornozelo decorrente de sequela de AVE, a fim de realizar eventuais ajustes antes que o equipamento seja incorporado na prática clínica. A metodologia consistiu em verificar a adequação ergonômica e técnica do equipamento, e avaliar a satisfação do usuário após o seu uso por meio de questionário. O aparelho foi avaliado tanto em pacientes com déficit motor de hemiparesia, como em indivíduos sem deficiências. Os resultados experimentais mostram que o equipamento é adequado como um recurso auxiliar na avaliação da amplitude de movimento articular do tornozelo e da força muscular, beneficiando os terapeutas na avaliação dos ganhos reais obtidos com as terapias. A partir das respostas ao questionário, verifica-se que os indivíduos sentiram-se satisfeitos com o recurso. Portanto, conclui-se que a PRRT é um recurso auxiliar promissor no tratamento do tornozelo de indivíduos que sofreram lesão neurológica, podendo trazer benefícios em relação à amplitude de movimento e ganho de força, além de proporcionar uma terapia prazerosa e estimulante aos pacientes. / Cerebrovascular diseases, including stroke, are the second leading cause of death worldwide and the leading cause of disability in the adult population. Due to cortical reorganization, the earlier rehabilitation is performed, the better the results. In this way, new treatments and technological solutions were developed to meet the challenges of rehabilitation after stroke, for example, increase of intensity and duration of therapy including external manipulation, bilateral movement training, and rehabilitation robotics. Robotic devices allow performing specific tasks repeatedly in a controlled and reliable way, a key factor for cortical reorganization, with increase of motor skills and improvement of functional activities performance. The main objective of this work was to verify the adequacy and usability of the Robotic Platform for Ankle Rehabilitation in post-stroke patients who need ankle rehabilitation, in order to make any necessary adjustments before the equipment be incorporated into clinical practice. The methodology consisted in verifying ergonomic and technical adequacy, and evaluates user satisfaction after use through a questionnaire. The device was evaluated in patients with motor deficit of hemiparesis, as well as in individuals without disabilities. Experimental results show the proposed equipment is suitable as an auxiliary resource in evaluating the range of motion and muscle strength of the ankle, assisting therapists in the evaluation of real gains obtained with the therapies. From the questionnaire responses, the individuals said they were satisfied with the resource. Therefore, it is concluded that the PRRT is a promising auxiliary resource in the treatment of individuals who have suffered neurological damage, bringing benefits with relation to range of motion and muscle strength, as well as providing pleasurable and stimulating therapy to patients.