Hip & Spine Mechanics - Understanding the linkage from several perspectives of injury mechanisms to rehabilitation using biomechanical modelling

One recent megatrend in medicine is that of “precision medicine” whereby a precise diagnosis leads to a precise intervention for superior results. This thesis was undertaken to enhance the understanding of spine and hip interactions and facilitate precision in both detection and the intervention of mechanical and neurological based disorders. The hip and spine are highly integrated structures. In order to adequately examine and improve the understanding of the complex mechanical linkage between the two, development of a highly biofidelic Hip-Spine Model (HSM) was pursued. Given that no model existed that incorporated the necessary detail, several challenges regarding model development needed to be addressed. It was clear that biofidelity of the model depended on a better understanding and representation of the passive hip stiffness in both males and females. Thus, the experimental data of passive stiffness was evaluated in conjunction with the HSM passive stiffness model predictions. Next, known Anterior Cruciate Ligament (ACL) injury risk factors, such as dynamic knee valgus (DKV) were examined in a female population where both the kinetic and kinematic variables of the hip and spine were evaluated to assist in differentiating those deemed at-risk and not-at-risk during the drop vertical jump (DVJ) procedure. Finally, an atlas of rehabilitation exercises was constructed to guide program design and progression/regressions of rehabilitation protocols for those with back and hip concerns. Each of these themes were unified around the overall goal of this thesis, that being the understanding of the hip-spine mechanical linkage pertaining to injury mechanisms and a guide for rehabilitation of hip-spine disorders. The first task was the development of the HSM. This model is anatomically detailed and driven by biological signals obtained from the individual to provide new insights into the understanding of the linkage in a way that was sensitive to the unique movement strategies of the individual. The HSM is an expansion of the previously established ‘Spine Model’ (SM), developed by Stuart McGill and his team over the past 37 years. The model anatomy was expanded from the current SM using the most complete single subject lower limb data set available know as the Twente Lower Extremity Model (TLEM). Hip ligaments were also added to enhance the passive behaviour of the model. An electromyographic (EMG) driven approach with subject specific kinematics was used to compute the model outputs that consisted of tissue and joint loads. Thus, the first objective of this thesis was to examine the interactions of hip and spine mechanics using a newly developed Hip-Spine Model (HSM) and then to investigate a spectrum of injury mechanisms and rehabilitation exercises. The next objective was to evaluate passive hip stiffness to enhance the biofidelity of the model and the understanding of hip mechanics in both males and females. A novel testing apparatus was designed and fabricated for measuring hip stiffness which could easily be adapted to clinical settings. This study also serves to establish normative baselines for passive hip stiffness in vivo. The third objective of this thesis was to examine issues of normal function and potential injury mechanisms. For example, ACL injury risk has been linked with some knee kinematic and kinetic patterns however, hip and spine interactions have not been appropriately explored nor have neuromuscular control strategies. This thesis linked the mechanical variables which differentiate at-risk landings of the DVJ task versus non-at-risk landing in females to enhance the understanding of risk behaviours. Clear differences in hip and spine control were documented to differentiate high and low valgus landings. Adding this knowledge to the current understanding of ACL injury risk will lead to the development of superior and more specific coaching cues to decrease tissue stress/strain concentrations. This approach will underpin intervention strategies leading to lower risk behaviour and correspondingly lower injury risk among female athletes. The final objective of this thesis was to evaluate the appropriateness of rehabilitation exercises to address hip spine disorders. Currently, there exists a myriad of exercises but little evidence to guide clinical reasoning or decisions for exercise choice, progression, volume and technique. Currently missing from the literature is knowledge of tissue and joint loads in combination with muscle activation patterns. This knowledge will facilitate better matching of specific exercises for specific disorders. The main objectives of this thesis were: (1) The development of the anatomically detailed, biologically driven HSM which successfully computes joint and tissue loads unique to the individual and their neuromuscular control strategy. (2) The establishment of passive hip stiffness for males and females. (3) To enhance understanding of both neurological and tissue loading characteristics associated with ACL injury risk which when added to the current knowledge provides the opportunity for more precise interventions. (4) The beginning of the development of an atlas for rehabilitation exercises to guide prescriptions that can be matched to specific hip-spine disorders. These findings have the potential to enhance precision medicine in the area of musculoskeletal health – where precision medicine is currently lacking

The contribution of behaviour to falls among older people in and around the home

This thesis examines the contribution of behaviour to falls among older people in and around the home. Falls are an extensive problem, with the scale of this set to worsen in line with the increasing older population. Risk factors for falls have received much attention during recent years, although little emphasis has been given to the role of behaviour in falls risk. It is argued in the thesis that older people play an active role in their exposure to risk, influenced by their attitudes, beliefs and motivations. This aspect has received only limited consideration. The research consisted of five studies. The first three investigations used a triangulated approach to examine the contribution and role of older people's behaviour, physical ability and home environment design in fall risk. The fourth study considered the role of health practitioners in fall prevention and investigated barriers to successful interventions. The final study examined the contribution of a health psychology framework to understanding fall-related behaviour among older people. [Continues.

Estimation of Transition Frequency Phase of Postural Coordination during Continuous Support Surface Translation

2019年

Contributions to successful trip recovery in younger and older adults

EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Recent Experiences in Multidisciplinary Analysis and Optimization, part 1

Papers presented at the NASA Symposium on Recent Experiences in Multidisciplinary Analysis and Optimization held at NASA Langley Research Center, Hampton, Virginia April 24 to 26, 1984 are given. The purposes of the symposium were to exchange information about the status of the application of optimization and associated analyses in industry or research laboratories to real life problems and to examine the directions of future developments. Information exchange has encompassed the following: (1) examples of successful applications; (2) attempt and failure examples; (3) identification of potential applications and benefits; (4) synergistic effects of optimized interaction and trade-offs occurring among two or more engineering disciplines and/or subsystems in a system; and (5) traditional organization of a design process as a vehicle for or an impediment to the progress in the design methodology

Worker and Public Health and Safety

This book on "Worker and Public Health and Safety: Current Views" brings together current scholarly work and opinions in the form of original papers and reviews related to this field of study. It provides important and recent scientific reading as well as topical medical and occupational information and research in areas of immediate relevance, such as chronic and occupational diseases, worker safety and performance, job strain, workload, injuries, accident and errors, risks and management, fitness, burnout, psychological and mental disorders including stress, therapy, job satisfaction, musculoskeletal symptoms and pain, socio-economic factors, dust pollution, pesticides, noise, pathogens, and related areas

Our Day Has Finally Come: Domestic Worker Organizing in New York City

This dissertation tells the story of Domestic Workers United (DWU), an organization of Latina and Caribbean nannies, housecleaners and elder care providers based in New York City. I trace DWU\u27s efforts from its campaign to win basic employment protections for domestic workers in New York State through its efforts to enforce those new rights and to raise working standards above the minimum. The driving motivation behind this work is the search for new paradigms for worker organizing that respond to the political and economic challenges of our times. I argue that domestic workers and other low-wage workers of color are the paradigmatic workers of the 21st century. The dynamics of the domestic work industry are an extreme expression of broader trends towards decentralization, informalization, low-wage work and commodified reproductive labor. DWU is part of a national movement of domestic workers\u27 organizations that are developing new organizing models that can help workers in other industries navigate these trends. Domestic Workers United\u27s work highlights the constraining and stratified models of economic citizenship that shaped labor politics in the last century, suggesting a more expansive, integrative and dynamic approach to worker organizing. Their work provides an example of an intersectional approach in which the incorporation of work to address race and gender oppression expands the terrain of class struggle, rather than narrowing it. DWU\u27s model also points towards the need to re-imagine economic citizenship and to conceptualize a new social contract. Their work indicates that, in order to respond to the dynamics of our times, we need to radically expand the realm of state protections, and it also suggests that we need to transform the framework of collective bargaining in the United States in order to enable effective negotiations between workers and employers. DWU\u27s implicit vision for a new social contract also offers a space for contestation over the social organization of reproductive labor. Finally, DWU\u27s demonstrates the need for more complex and dynamic approaches to understanding class relations and workers\u27 struggles that works through the racialized and classed differences between working people rather than focusing only on their shared experiences