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An investigation of the NHS service provision of prosthetic limbsSmalley, Grace January 2013 (has links)
This thesis explores the NHS Service provision of prosthetic limbs from a patient centred perspective. Amputation is the removal of a limb either for medical reasons or through trauma. The amputated limb can be replaced with a manufactured device to help the patient regain movement and as much function as possible. This device is known as a prosthesis and is given to the patient by the NHS at a Disablement Services Centre (DSC). There has been increasing negative media coverage of the NHS and the service it provides with specific reference to the Postcode lottery which has allegedly become apparent. This research aims to ascertain whether the service being provided at DSCs across the UK is satisfactory to patients and how this service can be improved. The literature surrounding amputation rehabilitation and care pathways is reviewed (Chapter 2). Research philosophies and approaches are discussed (Chapter 3). A countrywide study of NHS Disablement Services Centres was conducted to ascertain how the centres functioned and the differences in service between centres (Chapter 4). The data collected from this study were used to create a questionnaire for amputees to ascertain their opinions on the service they received at their centre (Chapter 5). The data revealed that patients had many problems with the service they received, very few of which could readily be acted upon due to budget restrictions. An investigation into patient s opinions on information provision was conducted as information provision was a problem highlighted by patients that could be influenced by further research (Chapter 6). Data gathered from all three studies were used to produce a proposed clinical pathway for Disablement Services Centres to follow with a new patient (Chapter 7). The proposed pathway was critically evaluated by prosthetists at a clinical conference and improvements to the proposed pathway were made using their suggestions (Chapter 7). The benefits, drawbacks and threats to the use of the proposed pathway were discussed both from the patient and clinical perspective (Chapter 8). The work was completed by overall conclusions and a discussion of further work (Chapter 9).
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The influence of limb alignment on the gait of above-knee amputeesYang, Lang January 1988 (has links)
Alignment of the above-knee prostheses is one of the important factors affecting the success of patient/prosthesis matching. It has been found that the prosthetist and the patient can accept a number of alignments which produce different intersegmental loads and it has been suggested that it is possible to obtain an 'optimal' alignment satisfying certain criteria. In order to enhance the efficiency of the alignment procedure, it is necessary to understand how alignment affects the amputee's gait and the patient compensations for changes in the alignment. Biomechanical gait tests on above-knee amputees were conducted in which the alignment of the prosthesis was changed systematically. The Strathclyde television-computer system was used to record the kinematic data of the amputee, and the ground reactions were measured by two Kistler forceplates. An 8-segment biomechanical model of the above-knee amputee was developed and implemented by a suit of FORTRAN computer programs to analyze and present 3-D kinematic and kinetic data obtained. The effects of alignment changes on the above-knee amputees' gait were studied in terms of the temporal-distance parameters, angular displacements of the lower limbs and the trunk, ground reactions and intersegmental moments. It was found that the angular displacement at the hip joint on the prosthetic side showed compensatory actions of the amputee for the alignment changes. The ground reaction force was sensitive to alignment changes, and in particular, the changes in the characteristics of the fore-aft ground force could be related to the alignment changes. The antero-posterior intersegmental moments about the prosthetic ankle and knee joints were evidently influenced by alignment.
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EFFECT OF COMPOSITION ON PERIPROSTHETIC FLUID RHEOLOGY AND FRICTION IN TOTAL KNEE ARTHROPLASTYFAM, Hala 27 September 2010 (has links)
The present thesis investigates the friction properties of total knee replacement components using lubricating fluids of different composition and rheology. The first stage of the thesis involves characterization of the rheological properties of hyaluronic acid (HA)/bovine calf serum (BCS) solutions. With increased concentration and molecular weight of HA, higher viscosities and more pronounced shear thinning in steady shear flow was observed. In dynamic oscillatory flow, the elastic character of the solutions became more pronounced and the cross-over frequency decreased upon increasing concentration and molecular weight of HA.
The second part of the thesis involves the determination of a method by which the coefficient of friction is estimated using a linear reciprocating wear testing machine with spherical metal indenters articulating on flat UHMWPE samples and deionised (D.I.) water lubrication. A characteristic periodic pattern in the friction behaviour was observed and the coefficient of friction was computed by calculating the average of 30 points about the midpoint between reversals and using the average of three cycles.
The third part of the thesis involves the investigation of the effect of fluid composition on the coefficient of friction in knee replacement components. With increased concentration of HA in solution (0-1mg/mL), the coefficient of friction of HA/BCS solutions decreased. However, with HA/BCS solutions of higher HA concentrations (above 1mg/mL), no significant difference in the coefficient of friction was observed. Similar behavior was observed with HA/Albumin solutions. With HA/ D.I. water solutions, the coefficient of friction was almost identical irrespective of the concentration of HA in solution. Significant difference in the rheological properties of HA/D.I. water solutions did not affect the coefficient of friction. The Stribeck analysis revealed that the coefficient of friction with HA/BCS and HA/D.I. water lubrication was not governed by hydrodynamic conditions.
The fourth part of this thesis involved characterization of lubricating fluids before and after friction testing. Absorbance and dynamic light scattering measurements of HA/BCS solutions and of HA/Albumin solutions indicate a rise in turbidity and the presence of larger size particles in these solutions after friction testing. The ninhydrin test confirmed the presence of protein in the precipitates obtained following testing. / Thesis (Ph.D, Chemical Engineering) -- Queen's University, 2010-09-24 14:06:41.437
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Investigations into the feasibility of digital neuromorphic signal processing circuitsLim, Seow-Chuan January 1999 (has links)
Modelling of the mammalian auditory system is valuable in understanding perception processes and has benefits in the design of signal processing systems and human prosthetic implants. However, as models increase in complexity, traditional methods of modelling using general purpose computers become very slow. One method of overcoming this is to use electronic implementations of these models. This thesis looks into the feasibility of auditory system implementations in digital technology, through the implementation of the Four-Stage Pitch System for pitch detection in hearing proposed by Hewitt and Meddis.
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Development of 2D Ultrasound Tracking Software and Hardware to Monitor Multiple Flexor Tendon Displacement for Applications Toward Hand ProsthesesStegman, Kelly J. 03 January 2014 (has links)
This thesis work provides a new way to detect and track the displacement of flexor tendons within the human arm, using a non-invasive, ultrasound-based, speckle tracking technique. By tracking the tendons in the arm, it provides a way to monitor a person’s intention to move their hands and fingers. This has application to hand prosthetic control, as well as tendon injury assessment, which has significant contributions to the medical and rehabilitation community. The system works by capturing and processing a sequence of B-scan ultrasound images, to detect and track the flexor tendon motion (excursion) in the wrist, as the user flexes their muscles. Given the biomechanics of the hand, tendon displacement is correlated to the user’s intention to move their finger. Several speckle tracking techniques using B-scan ultrasound image sequences are developed in this work, including: auto-location of the tendon, a stationary ROI (region of interest), and novel use of similarity measures such as FT (Fisher Tippett), and hybrid methods. As well, work is done to investigate various speckle tracking parameters, and their effects on tracking accuracy. The different speckle tracking techniques are developed using data obtained from cadaver hands, and human volunteers undergoing regular surgery. The tracking techniques are compared in terms of successfully detecting the tendon, accurately tracking tendon displacement, successfully tracking multiple tendons, successfully detecting and tracking the onset of low tendon displacement, and computational efficiency of the algorithms. Another major aspect of this work is the design of a novel quad-array transducer that can collect image sequences from up to four tendons simultaneously. This transducer is instrumental to the motivation for controlling an advanced prosthesis. As well, specialized hardware is designed for the cadaver-based studies. Overall, this thesis successfully demonstrated the proposed tracking algorithms and newly designed hardware, for tracking the displacement of single and multiple flexor tendons. It has provided several important contributions to the field. / Graduate / 0548 / 0986 / 0760
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Tactile Feedback for Dexterous Manipulation Operations using Assistive Prosthetic FingersKucherhan, Daniel January 2017 (has links)
Dexterous manipulation operations using robotic or prosthetic fingers is seemingly facilitated with enhanced tactile feedback. Using a combination of artificial sensors and actuators, a tactile feedback system that conveys tactual information (force, pressure, & temperature) from an artificial fingertip to the user’s hand is developed and tested with subjects. Results reveal that subjects are capable of distinguishing specific actuators with a high degree of accuracy. The sensor density and actuator fidelity of the feedback system is insufficient to yield performance equal to that of a human’s natural tactile senses. Future studies are recommended to identify optimal tactile feedback sites as well as to discover a more robust system to be used in robotic and immersive virtual reality contexts.
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Preliminary Study of Artificial Intervertebral DiscYeh, Ming-Chiang Jerry 08 1900 (has links)
<p> This study is one of the projects of the artificial joints group conducted by Professor W. R. Newcombe, Department of Mechanical Engineering and Dr. G. R. Viviani, Department of Surgery.</p> <p> A summary of the literature survey of the lower back which is pertinent to the design of a replacement for the lumbar spine is reported. Motions, force system, and
strengths of the lumbar intervertebral joint are obtained from the literatures and calculation.</p> <p> Advantages of silicone elastomer and titanium as the biomaterials for the artificial disc are presented. An experiment to test the bond between titanium and silicone reveals that the strength provided by only applying primer is insufficient.</p> <p> Surface structure for prosthetic stabilization and initial fixation is discussed. Proposed design alternatives for artificial discs are presented with the attempts to reduce the number of moulds needed by introducing a prosthesis with a more regular shape.</p> <p> An important part of this thesis is to indicate the direction in which further work in this area should proceed.</p> / Thesis / Master of Engineering (MEngr)
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Specifying a hybrid, multiple material CAD system for next-generation prosthetic designBodkin, Troy L. January 2017 (has links)
For many years, the biggest issue that causes discomfort and hygiene issues for patients with lower limb amputations have been the interface between body and prosthetic, the socket. Often made of an inflexible, solid polymer that does not allow the residual limb to breathe or perspire and with no consideration for the changes in size and shape of the human body caused by changes in temperature or environment, inflammation, irritation and discomfort often cause reduced usage or outright rejection of the prosthetic by the patient in their day to day lives. To address these issues and move towards a future of improved quality of life for patients who suffer amputations, Loughborough University formed the Next Generation Prosthetics research cluster. This work is one of four multidisciplinary research studies conducted by members of this research cluster, focusing on the area of Computer Aided Design (CAD) for improving the interface with Additive Manufacture (AM) to solve some of the challenges presented with improving prosthetic socket design, with an aim to improve and streamline the process to enable the involvement of clinicians and patients in the design process. The research presented in this thesis is based on three primary studies. The first study involved the conception of a CAD criteria, deciding what features are needed to represent the various properties the future socket outlined by the research cluster needs. These criteria were then used for testing three CAD systems, one each from the Parametric, Non Uniform Rational Basis Spline (NURBS) and Polygon archetypes respectively. The result of these tests led to the creation of a hybrid control workflow, used as the basis for finding improvements. The second study explored emerging CAD solutions, various new systems or plug-ins that had opportunities to improve the control model. These solutions were tested individually in areas where they could improve the workflow, and the successful solutions were added to the hybrid workflow to improve and reduce the workflow further. The final study involved taking the knowledge gained from the literature and the first two studies in order to theorise how an ideal CAD system for producing future prosthetic sockets would work, with considerations for user interface issues as well as background CAD applications. The third study was then used to inform the final deliverable of this research, a software design specification that defines how the system would work. This specification was written as a challenge to the CAD community, hoping to inform and aid future advancements in CAD software. As a final stage of research validation, a number of members of the CAD community were contacted and interviewed about their feelings of the work produced and their feedback was taken in order to inform future research in this area.
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Systematic review of neural control and sensory feedback in prosthetic handsHafez, Mariam Ezzat 01 February 2023 (has links)
Limb loss has severe physical and psychological effects on individuals with upper limb amputations. Higher rates of prosthetic device abandonment has contributed to a need for prosthetic hands that are functional and comfortable for the user. Prosthetic hands have been abandoned for many reasons including weight, size, limited functionality, training time, and discomfort. An optimal prosthetic hand considers both neural control and sensory feedback. Neural control of the prosthetic is crucial to obtain accuracy and desirable functions. Popular methods of sensory feedback such as visual feedback are mentally exhausting and require constant focus from the user. Control and feedback of prosthetic devices differs based on the type of prosthetic. Passive, myoelectric, body-powered, electrocorticographic, adaptive, and sonomyographic prosthetic hand devices focus on a variety of hand movements and each utilizes different methods of control. It is also important to consider the biomaterials of prosthetic hands to enhance comfort and ease-of-use. Mechanical and AM-ULA testing ensure prosthetic hands can perform necessary movements for the user. To develop an ideal prosthetic hand, control and feedback must be considered along with comfort and functionality of the device.
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POTENTIAL OPTIMAL GAIT PERFORMANCE OF MAUCH S-N-S PROSTHETIC KNEE CONFIGURATIONS AS PREDICTED BY DYNAMIC MODELINGChien, Chih-Hao 23 December 2014 (has links)
No description available.
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