Development of biomechanical-based analysis tools for the evaluation of infringements and performance in race-walking

The study aims at developing an innovative biomechanical based methodology for the performance and infringements assessment in race-walking using a wearable inertial system

Body sensor networks: smart monitoring solutions after reconstructive surgery

Advances in reconstructive surgery are providing treatment options in the face of major trauma and cancer. Body Sensor Networks (BSN) have the potential to offer smart solutions to a range of clinical challenges. The aim of this thesis was to review the current state of the art devices, then develop and apply bespoke technologies developed by the Hamlyn Centre BSN engineering team supported by the EPSRC ESPRIT programme to deliver post-operative monitoring options for patients undergoing reconstructive surgery. A wireless optical sensor was developed to provide a continuous monitoring solution for free tissue transplants (free flaps). By recording backscattered light from 2 different source wavelengths, we were able to estimate the oxygenation of the superficial microvasculature. In a custom-made upper limb pressure cuff model, forearm deoxygenation measured by our sensor and gold standard equipment showed strong correlations, with incremental reductions in response to increased cuff inflation durations. Such a device might allow early detection of flap failure, optimising the likelihood of flap salvage. An ear-worn activity recognition sensor was utilised to provide a platform capable of facilitating objective assessment of functional mobility. This work evolved from an initial feasibility study in a knee replacement cohort, to a larger clinical trial designed to establish a novel mobility score in patients recovering from open tibial fractures (OTF). The Hamlyn Mobility Score (HMS) assesses mobility over 3 activities of daily living: walking, stair climbing, and standing from a chair. Sensor-derived parameters including variation in both temporal and force aspects of gait were validated to measure differences in performance in line with fracture severity, which also matched questionnaire-based assessments. Monitoring the OTF cohort over 12 months with the HMS allowed functional recovery to be profiled in great detail. Further, a novel finding of continued improvements in walking quality after a plateau in walking quantity was demonstrated objectively. The methods described in this thesis provide an opportunity to revamp the recovery paradigm through continuous, objective patient monitoring along with self-directed, personalised rehabilitation strategies, which has the potential to improve both the quality and cost-effectiveness of reconstructive surgery services.Open Acces

Cognitive and Psychosocial Factors Associated with Sarcopenia in Older Adults

Objectives: To describe the muscle mass, strength, and function of older adults living in residential care apartment complexes (RCACs) and examine the association between self-efficacy for exercise, depressive symptoms, social support and sarcopenia. The convergent validity of Muscle Mechanography (MM) when compared to the traditional muscle function and strength tests was also tested. Design: Secondary data analysis of baseline data from a clinical trial. Setting: One RCAC in the Midwestern United States. Participants: Thirty-one older adults living in one RCAC. Measurement: Muscle mass was measured by bioelectrical impedance spectroscopy. Muscle function was evaluated by the Short Physical Performance Battery test, Timed Up and Go test, and MM. Grip strength was measured by a Jamar® hand dynamometer. Self-efficacy for exercise was measured by the Self-efficacy for Exercise Scale. Depressive symptoms were measured by the Geriatric Depression Scale. Social support was measured by the Lubben Social Network Scale. Results: Participants had lower values of muscle mass, strength, and function compared to values obtained in previous research. A sex difference exists for muscle mass, strength, and function. The findings showed a trend for individuals with high self-efficacy, without depressive symptoms, and with strong social support to present greater muscle mass, strength, and function. The findings also demonstrated convergent validity across all the examined measures of muscle function and strength. Conclusion: This study is only one of a few to describe the muscle outcomes and evaluate the relationship between selected cognitive and psychosocial factors and sarcopenia among older adults living in RCACs. The preliminary findings of this study warrant further investigation of an intervention aimed at maintaining or improving the muscle outcomes of RCAC residents. While the interpretation of findings should be presented with caution and replicated with other samples, this study may provide a new understanding about the muscle outcomes and the relationship between self-efficacy for exercise, depressive symptoms, and social support and sarcopenia. Improved understanding of muscle outcomes and the relationship between cognitive and psychosocial factors and sarcopenia is crucial. The findings also provided a new evidence about MM as a new technology to quantitively assess muscle function in older adults, potentially making this a valuable research tool

Sit-to-Stand Phases Detection by Inertial Sensors

The Sit-to-Stand(STS) is defined as the transition from the sitting to standing position. It is commonly adopted in clinical practice because musculoskeletal or neurological degenerative disorders, as well as the natural process of ageing, deter-mine an increased difficulty in rising up from a seated position. This study aimed to detect the Sit To Stand phases using data from inertial sensors. Due to the high variability of this movement, and, consequently the difficulty to define events by thresholds, we used the machine learning. We collected data from 27 participants (13 females,24.37\ub13.32 years old). They wore 10 Inertial Sensors placed on: trunk,back(L4-L5),left and right thigh, tibia, and ankles. The par-ticipants were asked to stand from an height adjustable chair for 10 times. The STS exercises were recorded separately. The starting and ending points of each phase were identified by key events. The pre-processing included phases splitting in epochs. The features extracted were: mean, standard deviation, RMS, Max and min, COV and first derivative. The features were on the epochs for each sensor. To identify the most fitting classifier, two classifier algorithms,K-nearest Neighbours( KNN) and Support Vector Machine (SVM) were trained. From the data recorded, four dataset were created varying the epochs duration, the number of sensors. The validation model used to train the classifier. As validation model, we compared the results of classifiers trained using Kfold and Leave One Subject out (LOSO) models. The classifier performances were evaluated by confusion matrices and the F1 scores. The classifiers trained using LOSO technique as validation model showed higher values of predictive accuracy than the ones trained using Kfold. The predictive accuracy of KNN and SVM were reported below: \u2022 KFold \u2013 mean of overall predictive accuracy KNN: 0.75; F1 score: REST 0.86, TRUNK LEANING 0.35,STANDING 0.60,BALANCE 0.54, SITTING 0.55 \u2013 mean of overall predictive accuracy SVM: 0.75; F1 score: REST 0.89, TRUNK LEANING 0.48,STANDING 0.48,BALANCE 0.59, SITTING 0.62 \u2022 LOSO \u2013 mean of overall predictive accuracy KNN: 0.93; F1 score: REST 0.96, TRUNK LEANING 0.79,STANDING 0.89,BALANCE 0.95, SITTING 0.88 \u2013 mean of overall predictive accuracy SVM: 0.95; F1 score phases: REST 0.98, TRUNK LEANING 0.86,STANDING 0.91,BALANCE 0.98, SIT-TING 0.9

Effects of Progressive Lens Eyeglasses on Gait Performance Factors Among Young and Middle-Aged Groups

Background: It is estimated that over 85% of adults over the age of 45 develop a condition called presbyopia (Holden et al., 2008). Multifocal lenses (MfLs) are used to functionally adapt to this condition to allow for convenient near and distance vision. However, this causes vision distortion in the lower part of the visual field at ground level while walking. Since safe ambulation relies on the lower visual field to detect obstacles (Marigold et al., 2008), and vision acts as a moderating factor for increased fall rates as individuals age (Heasley et al., 2005), there is a need to investigate the connection between MfLs, falls, and age. Objective: This study hypothesized that when wearing MfLs, both young and middle-aged individuals would experience a significant decrease in functional gait performance when compared to wearing single lenses. In addition, non-experienced MfLs wearers would both show similar within group gait performance decrement. Methods: Sixteen 18-35 year olds and seven 45-60 year old novice MfL wearers with no history of balance or gait impairments participated. A within-between subjects repeated measures ANOVA and t-tests evaluated the effects of MfLs and age on toe clearance, step force, and functional gait (the Dynamic Gait Index-Modified). Results: A statistically significant difference in toe clearance and DGI-m scores were found for young and middle-aged individuals between lens conditions. Young group: increase in toe clearance (t=4.801, p=.000) and decrease in DGI-m scores (t=-3.9, p=.001); Middle-aged group: increase in toe clearance (t=3.230, p=.018) and decrease in DGI-m (t=3.092, p=.021). No significant difference between groups was found (DGI-m F=.020, p=.836, toe clearance F=.015, p=.905, and maximum force F=.463, p=.505). Due to the multiple t- tests performed, an adjustment of a .0125 alpha was used for a significance threshold. Conclusion: MfLs appear to not only degrade visual performance, but also degrades key components of gait performance. The results of this study provided evidence that contributes to the validation of MfLs as a possible fall risk

Intelligent Sensors for Human Motion Analysis

The book, "Intelligent Sensors for Human Motion Analysis," contains 17 articles published in the Special Issue of the Sensors journal. These articles deal with many aspects related to the analysis of human movement. New techniques and methods for pose estimation, gait recognition, and fall detection have been proposed and verified. Some of them will trigger further research, and some may become the backbone of commercial systems

Physiotherapy for Parkinson's disease: a comparison of techniques (Review)

Background: Despite medical therapies and surgical interventions for Parkinson's disease (PD), patients develop progressive disability. The role of physiotherapy is to maximise functional ability and minimise secondary complications through movement rehabilitation within a context of education and support for the whole person. The overall aim is to optimise independence, safety and wellbeing, thereby enhancing quality of life. Trials have shown that physiotherapy has short-term benefits in PD. However, which physiotherapy intervention is most effective remains unclear. Objectives: To assess the effectiveness of one physiotherapy intervention compared with a second approach in patients with PD. Search methods: Relevant trials were identified by electronic searches of numerous literature databases (for example MEDLINE, EMBASE) and trial registers, plus handsearching of major journals, abstract books, conference proceedings and reference lists of retrieved publications. The literature search included trials published up to the end of January 2012. Selection criteria: Randomised controlled trials of one physiotherapy intervention versus another physiotherapy intervention in patients with PD. Data collection and analysis: Data were abstracted independently from each paper by two authors. Trials were classified into the following intervention comparisons: general physiotherapy, exercise, treadmill training, cueing, dance and martial arts. Main results: A total of 43 trials were identified with 1673 participants. All trials used small patient numbers (average trial size of 39 participants); the methods of randomisation and concealment of allocation were poor or not stated in most trials. Blinded assessors were used in just over half of the trials and only 10 stated that they used intention-to-treat analysis.A wide variety of validated and customised outcome measures were used to assess the effectiveness of physiotherapy interventions. The most frequently reported physiotherapy outcomes were gait speed and timed up and go, in 19 and 15 trials respectively. Only five of the 43 trials reported data on falls (12%). The motor subscales of the Unified Parkinson?s Disease Rating Scale and Parkinson?s Disease Questionnaire-39 were the most commonly reported clinician-rated disability and patient-rated quality of life outcome measures, used in 22 and 13 trials respectively. The content and delivery of the physiotherapy interventions varied widely in the trials included within this review, so no quantitative meta-analysis could be performed. Authors' conclusions: Considering the small number of participants examined, the methodological flaws in many of the studies, the possibility of publication bias, and the variety of interventions, formal comparison of the different physiotherapy techniques could not be performed. There is insufficient evidence to support or refute the effectiveness of one physiotherapy intervention over another in PD.This review shows that a wide range of physiotherapy interventions to treat PD have been tested . There is a need for more specific trials with improved treatment strategies to underpin the most appropriate choice of physiotherapy intervention and the outcomes measured

QUANTIFYING GAIT ADAPTABILITY: FRACTALITY, COMPLEXITY, AND STABILITY DURING ASYMMETRIC WALKING

Successful walking necessitates modifying locomotor patterns when encountering organism, task, or environmental constraints. The structure of stride-to-stride variance (fractal dynamics) may represent the adaptive capacity of the locomotor system. To date, however, fractal dynamics have been assessed during unperturbed walking. Quantifying gait adaptability requires tasks that compel locomotor patterns to adapt. The purpose of this dissertation was to determine the potential relationship between fractal dynamics and gait adaptability. The studies presented herein represent a necessary endeavor to incorporate both an analysis of gait fractal dynamics and a task requiring adaptation of locomotor patterns. The adaptation task involved walking asymmetrically on a split-belt treadmill, whereby individuals adapted the relative phasing between legs. This experimental design provided a better understanding of the prospective relationship between fractal dynamics and adaptive capacity. Results from the first study indicated there was no association between unperturbed walking fractal dynamics and gait adaptability in young, healthy adults. However, there was an emergent relationship between asymmetric walking fractal dynamics and gait adaptability. Moreover, fractal dynamics increased during asymmetric walking. The second study investigated fractal dynamics and gait adaptability in healthy, active young and older adults. The findings from study 2 showed no differences between young and older adults regarding unperturbed or asymmetric walking fractal dynamics, or gait adaptability performance. The second study provided further evidence for the lack of association between unperturbed fractal dynamics and gait adaptability. Furthermore, study 2 delivered additional support that asymmetric walking not only yields increased fractal scaling values, but also associates with adaptive gait performance in older adults. Finally, while the first two studies explored stride time monofractality during various walking tasks, the third study aimed to understand the potential multifractality, i.e. temporal evolution of fractal dynamics, of unperturbed and asymmetric walking. The results suggest that unperturbed walking is monofractal in nature, while more challenging asymmetric walking reveals multifractal characteristics, and that multifractality does not associate with adaptive gait performance. This dissertation provides preliminary evidence for the lack of relationship between gait adaptability and unperturbed fractal dynamics, and the emergent association between adaptive gait and asymmetric walking fractality