O presente estudo objetivou analisar a relação do índice do arco plantar com o equilíbrio postural e com a frequência do uso do salto alto entre mulheres de diferentes faixas etárias. Participaram do estudo 60 mulheres, 20 no grupo jovem (GJ), 20 no grupo adulto (GA) e 20 do grupo idoso (GI), as quais foram separadas em subgrupos com 10 indivíduos cada de acordo com a frequência do uso do salto alto. A avaliação da frequência do uso do sapato de salto alto foi realizada através do número de vezes que o indivíduo utilizava esse tipo de calçado. Para o cálculo do índice do arco plantar (IAP) utilizou-se o método de impressão plantar, por meio de um pedígrafo. Para a aquisição dos dados referentes ao equilíbrio postural foi utilizada uma plataforma de força AMTI; as variáveis utilizadas a partir do Centro de Pressão (COP) foram: amplitude de deslocamento ântero-posterior do centro de pressão (COPap), amplitude de deslocamento médio-lateral do COP (COPml), velocidade média de deslocamento do COP (COPvel) e área da elipse (elipse). Os resultados apontam que não houve correlações entre as variáveis do COP (COPap, COPml, velocidade e elipse) e o IAP na condição de olhos abertos e olhos fechados. Ao se tratar da faixa etária, houve diferença estatisticamente significativa entre o índice do arco plantar do GJ e GI e do GA e GI, indicando que o grupo de mulheres idosas possui um maior índice do arco plantar, ou seja, um rebaixamento no arco longitudinal medial. Com relação à frequência do uso do salto alto, não houve diferença estatisticamente significativa do índice do arco plantar entre os grupos. Concluiu-se que o índice do arco plantar não altera o controle postural em mulheres jovens, adultas e idosas deste estudo e que o grupo idoso apresenta um rebaixamento do arco longitudinal medial quando comparado com o grupo jovem e adulto. / The present study aimed to analyze the relationship between plantar arch index and postural balance and the frequency of use of high-heeled shoes among women of different age groups. The study included 60 women, 20 in the young group (GJ), 20 in the adult group (GA) and 20 in the elderly group (GI), which were separated into groups with 10 individuals each according to frequency of use of high-heeled shoes. The evaluation of the frequency of use of the high heel shoe was performed using the number of times that the person use this kind of footwear. To obtain the plantar arch index (IAP) was used the method of printing plant, with a plantar foot pressure. For acquisition of postural balance data was used a AMTI force plate and variables from the center of pressure (COP) used were: range of anteroposterior displacement of the center of pressure (COPap), range of displacement of the medial-lateral COP (COPml) and average speed of displacement of the COP (COPvel). The results showed that there were no correlations between the variables of COP (COPap, COPml, speed and ellipse) and IAP on eyes opened and eyes closed conditions. When dealing with the age group, there were statistically significant differences between the plantar arch index of the GJ and GI and of the GA and GI, indicating that the group of older women have an increased plantar arch index or a presents lower medial longitudinal arch. It was concluded that the plantar arch index does not alter postural control in young, adult and elderly people and that the elderly group presents lower medial longitudinal arch when compared with the young adult group showing.

Orientadores: Helder Anibal Hermini, Cecilia Amelia de Carvalho Zavaglia / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-13T00:54:31Z (GMT). No. of bitstreams: 1 Gaino_MartaRegianeCorrocher_M.pdf: 3846558 bytes, checksum: b58ca2b460c15132afc714592bd49e5e (MD5) Previous issue date: 2009 / Resumo: O rolamento dos pés é fundamental para uma marcha humana eficiente, mas o envelhecimento traz alterações em todos os sistemas corporais, causando também modificação no rolamento dos pés durante a deambulação e uma diminuição na eficiência da marcha. Este trabalho se propôs a criar um dispositivo para, simultaneamente, captar e registrar a sequência da distribuição de cargas na região plantar dos pés durante a marcha e fornecer estímulos sonoros que auxiliem o indivíduo na compreensão da seqüência correta de rolamento dos pés. O dispositivo foi idealizado e desenvolvido por uma equipe multidisciplinar, sendo testado inicialmente nos pés da equipe e em seguida em três sujeitos acima de 60 anos de idade, para realização de ajustes. Os dados colhidos pelo protótipo foram colocados em uma planilha Excel para análise. Em vista dos resultados, são sugeridas melhorias e formas de utilização do dispositivo, que pode ser uma alternativa para uso clínico, tanto para verificação das condições de rolamento do pé na marcha, quanto para o treinamento do mesmo através do "biofeedback" sonoro. Foi encontrada uma vantagem adicional no uso dos sensores de película sensíveis ao toque, uma vez que os mesmos forneceram também um estímulo para a sensibilidade plantar. Em conclusão sugerem-se possibilidades de aprimoramento e propõem-se novos testes. / Abstract: Feet roll-over is fundamental to assure an efficient human gait but aging brings body system's alterations that cause modifications in gait's feet roll-over and diminishes gait's efficiency. This work's proposal was to elaborate and develop a device in order to simultaneously acquire e record plantar load distribution during gait and to give sound stimuli that help aged people to understand the correct feet roll-over mechanism. The device has been idealized and developed by a multidisciplinary team. In order to verify the device efficiency or problems, it has been tried on by the researchers and in three persons above 60 years old, aiming to make adjustments. The collected data have been gathered in Excel spreadsheet in order to be analyzed. Improvements and use possibilities are suggested based in the results. The device can be an alternative to clinical procedures, both to feet roll-over verification or training with sound biofeedback. An additional advantage has been found since the touch pellicle sensors showed to be a good source of sensitive stimuli to the feet's plantar region. In conclusion, improvements and tests of usage possibilities have been suggested. / Mestrado / Projeto Mecanico / Mestre em Engenharia Mecânica

Indiana University-Purdue University Indianapolis (IUPUI) / Currently, changes to endogenous opioid circuits in various pain modalities, including surgical and neuropathic pain, remain unclear. Dynorphin, which is released by prodynorphin-expressing neurons (Pdyn+ neurons), is the endogenous opioid ligand to kappa opioid receptors (KOR). Moreover, a recent study has shown an increase in prodynorphin (Pdyn) mRNA expression in the prelimbic cortex (PL) in a mouse model of chronic pain. However, alterations in the activity of PL Pdyn-expressing neurons (PLPdyn+ neurons) in postoperative and chronic pain have never been explored. Firstly, I found that the population of PLPdyn+ neurons consists of both pyramidal and inhibitory subtypes. Secondly, I found that one day after surgical incision of the mouse hind paw, the excitability of pyramidal PLPdyn+ neurons was increased in both male and female mice, while the excitability of inhibitory PLPdyn+ neurons was unchanged. However, when postoperative pain behavior subsided, inhibitory PLPdyn+ neurons were hyperexcitable in male mice, while pyramidal PLPdyn+ neurons were hypoexcitable in female mice. Lastly, I dissected electrophysiological changes to PLPdyn+ neurons in the spared nerve injury (SNI) model of chronic neuropathic pain. At both early and late stages of SNI pain development, increased excitability of pyramidal PLPdyn+ neurons was detected in both male and female mice. However, in both male and female mice, the excitability of inhibitory PLPdyn+ neurons decreased 3 days after SNI but was conversely increased when measured 14 days after SNI. My findings suggest that different subtypes of PLPdyn+ neurons manifest distinct alterations in the development of different pain modalities in a sex-specific manner.

Yes / The mechanical output at the ankle provides key contribution to everyday activities, particularly step/stair ascent and descent. Age-related decline in ankle functioning can lead to an increased risk of falls on steps and stairs. The rising up-on-the-toes (UTT) 30-second test (UTT-30) is used in the clinical assessment of ankle muscle strength/function and endurance; the main outcome being how many repetitive UTT movements are completed. This preliminary study describes how inertial measurement units (IMUs) can be used to assess the UTT-30. Twenty adults (26.2 ± 7.7 years) performed a UTT-30 at a comfortable speed, with IMUs attached to the dorsal aspect of each foot. Use of IMUs’ angular velocity signal to detect the peak plantarflexion angular velocity (p-fAngVelpeak) associated with each repeated UTT movement indicated the number of UTT movements attempted by each participant. Any UTT movements that were performed with a p-fAngVelpeak 2SD below the mean were deemed to have not been completed over a sufficiently ‘full’ range. Findings highlight that use of IMUs can provide valid assessment of the UTT 30-second test. Their use detected the same number of attempted UTT movements as that observed by a researcher (average difference, -0.1 CI, -0.2 – 0.1), and on average 97.6 ± 3.1% of these movements were deemed to have been completed ‘fully’. We discuss the limitations of our approach for identifying the movements not completed fully, and how assessing the consistency in the magnitude of the repeated p-fAngVelpeak could be undertaken and what this would indicate about UTT-30 performance.

Purpose: The purpose of this dissertation was to determine the effects of chronic plantar fasciitis on intrinsic foot structures with respect to biomechanics, muscle atrophy and muscle energetics. This was accomplished in three parts. Methods: In Part I, a three-dimensional motion capture system with a synchronized force platform quantified multi-segment foot model kinematics and ground reaction forces associated with walking. Healthy individuals were compared to individuals with chronic plantar fasciitis feet. Typical kinematic variables, measures of coupling, phase and variability were examined in rearfoot, forefoot and hallux segments. In Part II, foot and leg magnetic resonance images were taken in subjects with unilateral plantar fasciitis so that within each subject, the healthy limb could be compared to the plantar fasciitis limb. Cross sectional areas (CSA) of the plantar intrinsic foot muscles (PIFM) and tibialis posterior muscle were computed from user-digitized images. In Part III, the metabolic demands of the PIFM were evaluated using phosphorous magnetic resonance spectroscopy at rest and after barefoot walking. Muscle pH and the ratio of inorganic phosphate to phosphocreatine (Pi/PCr) were compared in healthy and plantar fasciitis feet. Results: In comparison to healthy feet, plantar fasciitis feet exhibited significantly (p < 0.05): 1) greater rearfoot motion, 2) greater sagittal plane forefoot motion, 3) fewer rearfoot-forefoot frontal anti-phase movements, 4) reduced rearfoot-forefoot transverse coordinative variability, 5) greater first metatarsophalangeal (FMPJ) joint dorsiflexion, 6) greater FMPJ-medial longitudinal arch (MLA) coupling variability, and 7) decreased vertical ground reaction forces at propulsion. Also, plantar fasciitis feet had 5.2% smaller PIFM CSA at the forefoot compared to contralateral healthy feet. No CSA differences were seen in the rearfoot PIFM or at the tibialis posterior muscle. The PIFM of healthy and PF feet were not significantly different in resting intracellular levels of pH or Pi/PCr, and there were no significant differences in the increase of Pi/PCr from rest to postwalking. Conclusions: In Part I, it was concluded that plantar fasciitis feet exhibit kinematics which are consistent with theoretical causation of the plantar fasciitis injury, that is, the plantar fasciitis foot exhibits excessive motion. Fewer number of anti-phase movements exhibited by plantar fasciitis feet may be an indication of pathology. The ground reaction force results suggested a compensatory pain response. In Part II, it was concluded that atrophy of the forefoot PIFM may destabilize the medial longitudinal arch and prolong the healing process. Lastly in Part III, it was concluded that resting energetics were consistent with muscle free of systemic disease or neuromuscular pathology. The presence of plantar fasciitis did not elicit systematic asymmetries in the metabolic response in comparison to healthy feet. Clinical Relevance: These kinematic results provided some evidence to support the clinical assertion that excessive motion is related to plantar fasciitis. These results also support treatment modalities which clinicians currently use to reduce rearfoot eversion, flattening of the medial longitudinal arch and dorsiflexion of the FMPJ (e.g. foot orthoses, insoles, taping, rocker soles). When treating plantar fasciitis patients, clinicians should assess for PIFM and tibialis posterior muscle atrophy and prescribe targeted exercises when appropriate.

No description available.

Foot posture is an important characteristic that can affect kinematics, plantar loading, and injury risk. Arch height is one common aspect of foot posture, and it is estimated that about 60% of the population has normal arches while 40% of the population is either pes planus or pes cavus. It is important to be able to accurately and reliably assess foot posture characteristics in order to propose interventions that could prevent injuries due to abnormal foot alignment. However, despite multiple classification metrics, many of the devices that are commonly used for foot posture measurements are not economically feasible for smaller clinics or research labs. Therefore, the first purpose of this study was to develop an affordable device to measure different foot posture characteristics. The Foot Posture Measurement System was developed and can measure total foot length, truncated foot length, foot width, dorsum height, and navicular height. This system was shown to have good to excellent validity (ICC = 0.908-0.994) and repeatability (ICC = 0.867-0.996) when compared to a 3D scanner. This device was then used in the second portion of this study, which evaluated the effects of ankle braces on plantar loading patterns in individuals with different foot postures. Contact area, peak force, force-time integral, and center of pressure were evaluated during a walk, run, and cut while the participant was unbraced, wearing a lace-up stabilizer brace, and wearing a semi-rigid brace. It was demonstrated that arch height did affect the maximum plantar forces during all tasks (p=0.001-0.047), as hypothesized based on previous studies. Additionally, this study found that ankle braces affected contact area (p=0.001-0.0014), maximum force (p<0.001 – p=0.043), and force-time integral (p<0.001 – p=0.015) during the walk, run, and cut. This is a novel finding and points to the potential for an impact of ankle braces on plantar loading during athletic activities, independent of foot type. / Master of Science / Foot posture is an important characteristic that can affect daily life and contribute to the risk of injury. Arch height is one common aspect of foot posture, and it is estimated that about 60% of the population has normal arches while 40% of the population is either high arched or low arched/flat footed. It is important to be able to accurately and reliably assess foot posture characteristics in order to propose interventions that could prevent injuries due to abnormal foot alignment. However, despite multiple classification metrics, many of the devices that are commonly used for foot posture measurements are not economically feasible for smaller clinics or research labs. Therefore, the first purpose of this study was to develop an affordable device to measure different foot posture characteristics. The Foot Posture Measurement System was developed and can measure five different length, width, and height characteristics of the foot. This system was shown to be valid when compared to a 3D scanner and repeatable between days. This device was then used in the second portion of this study, which evaluated the effects of ankle braces on individuals with different foot postures. Four different force and pressure variables were examined within the foot during a walk, run, and cut while the participant was unbraced, wearing a lace-up stabilizer brace, and wearing a semi-rigid brace. It was shown that arch height did alter plantar loading measures during all tasks, as hypothesized based on previous studies. Additionally, this study found that ankle braces affected all variables during the walk, run, and cut. This is a novel finding and points to the potential for an impact of ankle braces on plantar loading during athletic activities, independent of foot type.

The prevalence of obesity is high in the United States. One of the many concerns with the high prevalence of obesity is its association with an increased risk of falls and subsequent injury. Thus, it is important to understand factors affecting falls among individuals who are obese, to help develop effective intervention solutions to mitigate falls in this population. Obese individuals have been hypothesized to have an impaired plantar sensitivity, and this may influence their balance control, thus lead to more falls. Executive function deficits in individuals who are obese may affect their ability to allocate attentional resources to dual tasks (walking while performing other tasks), and may put them at higher risks of falls. Gait alterations and muscle strength deficits in individuals who are obese may also increase their fall risks. Therefore, three studies were carried out to provide better understanding into the factors affecting falls in individuals who are obese. The first study investigated the effects of obesity on plantar sensitivity, and explored the relationship between plantar sensitivity and postural sway during quiet standing. Plantar sensitivity was measured as the force threshold at which an increasing force applied to the plantar surface of the foot was first perceived, and the force threshold at which a decreasing force was last perceived. Measurements were obtained while standing, and at two locations on the plantar surface of the dominant foot. Postural sway during quiet standing was then measured under three different sensory conditions. Results indicated less sensitive plantar sensitivity and increased postural sway among individuals who are obese, and statistically significant correlations between plantar sensitivity and postural sway that were characterized as weak to moderate in strength. As such, impaired plantar sensitivity among individuals who are obese may be a mechanism by which obesity degrades standing balance among these individuals. The second study investigated the influence of obesity on executive function, and determined whether there is a relationship between executive function and fall risk (as estimated from selected gait parameters). Four major components of executive function were assessed, including selective attention, divided attention, semantic memory and working memory. Both single- and dual-task walking (walking-while-talking) were completed to evaluate fall risk during gait. Less effective selective attention, semantic memory, and working memory were found among young obese adults. Participants exhibited higher fall risks during dual-task walking, and executive function scores were associated with gait during dual-task walking. In conclusion, obese individuals exhibited less effective executive function, which may be associated with their increased fall risk. The third study explored differences in gait, plantar sensitivity, executive function, lower extremity muscle strength, and body size between fallers and non-fallers, and the strength of the association between the same factors and slip severity. Participants' gait, plantar sensitivity, executive function, lower extremity muscle strength, and body size measures were obtained. An unexpected slip was introduced in a laboratory setting to obtain slip severity related measures and slip outcome. Results indicated obese fallers exhibited better executive function (selective attention), stronger lower extremity muscle strength, lower BMI and smaller waist circumference. Results also indicated increased slip severity was associated with faster walking speed, longer step length, higher RCOF, worse executive function (working memory), and lower BMI. Slower reactive recovery response was also associated with lower BMI. As such, better selective attention and stronger muscle strength exhibited limited benefit in slip recovery among individuals who are obese. Altered gait pattern, and working memory may be factors by which obesity increased slip severity, and lower BMI among individuals who are obese may increase slip-induced fall risks. In conclusion, reduced plantar sensitivity, impairments in executive function, altered gait pattern were associated with deficits in standing and walking balance control, and increased slip severity among individuals who are obese. Therefore, appropriate fall prevention/intervention program targeting at some or all of these factors may be considered as solutions to decrease fall risks for obese individuals. / Ph. D.

African Americans (AA) are twice as likely as White Americans (WA) to experience diabetes-related foot amputation due to foot ulcers. Foot ulcers are often caused by high plantar pressure, and several factors can impact plantar loading. Thus, there is a need to determine if race is a significant predictor of plantar loading. Additionally, with the current state of racial health disparities there is a need to determine racial differences in research engagement and mistrust between AA and WA. Data was collected from 107 participants, aged 18-30, in this Institutional Review Board approved study. An EMED pressure-measurement system (Novel Electronics, St. Paul, MN, USA) was used to collect plantar loading data. Additional measurements collected from each participant included arch height index (AHI), standing height, gait speed, and weight. Participants also completed two surveys focused on research engagement and research mistrust. A multiple linear regression was used to test if race and other factors significantly predicted plantar loading. Non-parametric tests were used to test if there were significant differences in research engagement and mistrust between AA and WA. The analysis determined that race was a significant predictor for plantar loading, along with age, AHI, gait speed, sex, and body mass index (BMI). Additionally, it was found that research engagement practices and feelings of research mistrust differed significantly between AA and WA young adults. These findings could improve our understanding as to why AA are more likely to have diabetic foot ulcers than WA, and why AA are less likely to participate in research than WA. / M.S. / African Americans (AA) are twice as likely than White Americans (WA) to experience diabetes-related foot amputation due to foot ulcers. Foot ulcers are often caused by high plantar pressure, and several factors can alter plantar loading. Thus, there is a need to determine if race is a significant predictor of plantar loading. Additionally, with the current state of racial health disparities, there is a need to determine racial differences in research engagement and mistrust between AA and WA. Data was collected from 107 participants, aged 18-30. A pressure-measurement system was used to collect plantar loading data in seven regions of the foot during self-selected speed walking. The measurements collected from each participant, included arch height, standing height, gait speed, and weight. Participants were also asked to complete two surveys focused on research engagement and research mistrust. We used this data to evaluate if race and other factors predicted plantar loading and to compare survey responses between AA and WA. It was found that race, age, arch height, gait speed, sex, and BMI were considered significant predictor variables for plantar loading measures. Additionally, research engagement practices and feelings of research mistrust differed significantly between this younger sample of AA and WA. These findings help to improve our understanding of why AA are more likely to have diabetic foot ulcers than WA, and why AA are less likely to participate in research than WA, even as young adults.

BACKGROUND:People who have extremely high arched feet or pes cavus often suffer from substantial foot pain. Custom-made foot orthoses (CFO) have been shown to be an effective treatment option, but their specificity is unclear. It is generally thought that one of the primary functions of CFO is redistributing abnormal plantar pressures. This study sought to identify variables associated with pain relief after CFO intervention.METHODS:Plantar pressure data from a randomized controlled trial of 154 participants with painful pes cavus were retrospectively re-analyzed at baseline and three month post CFO intervention. The participants were randomized to a treatment group given CFO or a control group given sham orthoses.RESULTS:No relationship between change in pressure magnitude and change in symptoms was found in either group. However, redistribution of plantar pressure, measured with the Dynamic Plantar Loading Index, had a significant effect on pain relief (p=0.001). Our final model predicted 73% of the variance in pain relief from CFO and consisted of initial pain level, BMI, foot alignment, and changes in both Dynamic Plantar Loading Index and pressure-time integral.CONCLUSION:Our data suggest that a primary function of effective orthotic therapy with CFO is redistribution of abnormal plantar pressures. Results of this study add to the growing body of literature providing mechanistic support for CFO providing pain relief in painful foot conditions. The proposed model may assist in better designing and assessing orthotic therapy for pain relief in patients suffering painful cavus foot deformity.TRIAL REGISTRATION:Randomized controlled trial: ISRCTN84913516