Losing a hand is a highly traumatic experience affecting both the physical life and mental wellbeing of a person. It is therefore vital to provide a prosthetic hand with similar functionality to the hand lost. The human hand is a very delicate and complex part of the body used every day in a wide range of tasks from performing heavier works to smaller gestures. Due to all factors playing arole in how amputees live their lives, recreating a human hand is a very demanding and challenging task. As many as 30% of amputees experience depression and/or anxiety as a result of not having the same capabilities and opportunities as before the amputation. Amputation may be carried out both due to sudden accidents and as a result of congenital defiances and vascular illnesses. Since advanced prosthetic hands often come in at a price too high to reach a large part of the amputee consumer base, the case is often that only the richest amputees are able to afford electric prosthetic devices, and are thus often limited to simpler, body-powered alternatives. These alternatives are often found to be lacking in features and resemblance when comparing to the more technologically advanced electric prosthetics. A set of product development tools and methods were selected for the development process to ensure an organized approach for the project. The project was concluded with a finished and fully-manufacturable prosthetic hand with some advantages compared to the current market products. The hand developed in the project, named OYMotion hand 1.0 proved to have a number of advantages over competing products in selected functional areas such as force, finger speed and weight. The final market price of the product could not be estimated due to the fact that there are too many unknown factors involved to determine a final market price on the hand. The production cost is, however estimated to be significantly lower than the measured competing prosthetic hands. A deepened understanding about prosthetic hand design and development was obtained by studying the market, EMG, machine learning applications, hardware, gears, finger mechanisms,and materials.  By balancing concepts between cost, functionality and aesthetics, a structured reasoning couldbe used to prioritize certain aspects of the developing of the hand.The completed hand fulfills the required specifications and functions after undergoing anumber of analyses conducted in order verify material strength and mechanism functionality.Further grip strength analyses and calculations were excluded from the study due to the limitedavailable time given.

Beginning with the introduction of electrically powered prostheses more than 65 years ago surface electromyographic (sEMG) signals recorded from residual muscles in amputated limbs have served as the primary source of upper-limb myoelectric prosthetic control. The majority of these devices use one or more neural interfaces to translate the sEMG signal amplitude into voltage control signals that drive the mechanical components of a prosthesis. In so doing, users are able to directly control the speed and direction of prosthetic actuation by varying the level of muscle activation and the associated sEMG signal amplitude. Consequently, in spite of decades of development, myoelectric prostheses are prone to highly variable functional control, leading to a relatively high-incidence of prosthetic abandonment among 23-35% of upper-limb amputees. Efforts to improve prosthetic control in recent years have led to the development and commercialization of neural interfaces that employ pattern recognition of sEMG signals recorded from multiple locations on a residual limb to map different intended movements. But while these advanced algorithms have made strident gains, there still exists substantial need for further improvement to increase the reliability of pattern recognition control solutions amongst the variability of muscle co-activation intensities. In efforts to enrich the control signals that form the basis for myoelectric control, I have been developing advanced algorithms as part of a next generation neural interface research and development, referred to as Motor Unit Drive (MU Drive), that is able to non-invasively extract the firings of individual motor units (MUs) from sEMG signals in real-time and translate the firings into smooth biomechanically informed control signals. These measurements of motor unit firing rates and recruitment naturally provide high-levels of motor control information from the peripheral nervous system for intact limbs and therefore hold the greater promise for restoring function for amputees. The goal for my doctoral work was to develop advanced algorithms for the MU Drive neural interface system, that leverage MU features to provide intuitive control of multiple degrees-of-freedom. To achieve this goal, I targeted 3 research aims: 1) Derive real-time MU-based control signals from motor unit firings, 2) Evaluate feasibility of motor unit action potential (MUAP) based discrimination of muscle intent 3) Design and evaluate MUAP-based motion Classification of motions of the arm and hand.

Introduction: Gram-negative prosthetic joint infections (GN-PJI) present unique challenges in management due to their distinct pathogenesis of biofilm formation on implant surfaces. The purpose of this study is to establish a clinically representative GN-PJI model that can reliably recapitulate biofilm formation on titanium implant surface in vivo. I hypothesized that biofilm formation on an implant surface will affect its ability to osseointegrate. Methods: The model was developed using 3D-printed titanium hip implants, to replace the femoral head of male Sprague-Dawley rats using a posterior surgical approach. GN-PJI was induced using two bioluminescent Pseudomonas aeruginosa (PA) strains: a reference strain (PA14-lux) and a mutant strain that is defective in biofilm formation (flgK-lux). Infection was assessed in real-time using the in vivo imaging system (IVIS) and Magnetic Resonance Imaging (MRI) and in vitro by quantifying bacterial loads on collected implants surface and in periprosthetic tissues as well as biofilm visualization using the Field emission scanning electron microscopy (FE-SEM). The implant stability, as an outcome, was directly assessed by quantifying the osseointegration in vitro using microCT scan, and indirectly assessed by identifying the gait pattern changes using DigiGaitTM system in vivo. Results: Bioluminescence detected by IVIS, was focused on the hip region, demonstrating localized-infection, with the ability of PA14-lux to persist in the model compared to flgK-lux defective in biofilm formation. This was corroborated by MRI as the PA14-lux induced relatively larger implant-related abscesses. Biofilm formation at the bone-implant-interface induced by the PA14-lux was visualized using FE-SEM versus defective-biofilm formation by flgK-lux. This could be quantitatively confirmed, by average viable-colony-count of the sonicated implants, 3.77x108CFU/ml versus 3.65x103CFU/ml for PA14-lux and flgK-lux, respectively (p=0.0025; 95%CI: -6.08x108 to -1.45x108). This difference in the ability to persist in the model was reflected significantly on the implant osseointegration with a mean intersection surface 4.1x106μm2 1.99x106 for PA14-lux versus 6.44x106μm2 2.53x106 for flgK-lux and 7.08x106μm2 1.55x106 for non-infected control (p=0.048). Conclusions: To date, the proposed in vivo biofilm-based model is the most clinically representative for GN-PJI since animals can bear weight on the implant and poor osseointegration correlates with biofilm formation. Clinical Relevance: The current model will allow for reliable testing of novel biofilm-targeting therapeutics.

Prosthetic heart valves (PHVs) are routinely used to replace defective native heart valves in patients suffering from valvular heart diseases. While PHVs are life-saving, they have limitations in performance and durability. Therefore, it is crucial to rigorously test and evaluate their designs before their implantation. PHVs are commonly examined using cardiovascular testing equipment that measures the hemodynamic characteristics of the valves, while also providing the opportunity for their visual assessment by collecting high-quality videos. Such visual data, obtained during mechanical simulations, are typically assessed by human experts, which is a tedious and error-prone task. Automatic assessment of PHVs from video data is possible, however, there are some challenges that need to be addressed. The evolution of the valve orifice area during one cardiac cycle is one of the key quality metrics for PHV visual assessment. Very fast motion of the valve’s leaflets is one of the challenges while dealing with the visual data. Nevertheless, the more important issue lies in the orifice being partly occluded by the inner side of the leaflets or inaccurately depicted due to its transparency. This issue has not been addressed in the literature. In the first part of the thesis, a novel orifice area segmentation algorithm is proposed for automatic quantitative performance analysis of PHVs, based on the leaflet free edges to accurately extract the actual orifice area. The video frames, recorded by a high-speed digital camera during in vitro simulations, are used to obtain an initial estimate of the orifice area using active contouring methods. This initial estimate is then refined to detect leaflet free edges via a curve extension scheme and considering brightness and smoothness criteria. Both of the developed algorithms are later modified for addressing challenges related to the fast motion of leaflets, automatic detection of the beginning of a cycle, and overly bright spots and narrow areas. Evaluation on several cases including three different PHVs and with different video qualities demonstrated the effectiveness of the proposed approach and adjustments in detecting valve leaflet free edges and extraction of the actual orifice area. The proposed method significantly outperforms a baseline algorithm both in terms of valve design and computer vision evaluation metrics. It can also cope with lower quality videos and is better at processing frames with a very small opening, which is a very crucial quality for determining the malfunctions related to improper closing of the valves. In the second part of the thesis, the above-mentioned segmented orifice area is used for the durability estimation of the prosthetic heart valves. More than 50% of PHVs encounter a structural failure within 15 years post-implantation mostly because of the excessive localized forces on some areas. We perform a computer vision (CV)-based analysis of the visual symmetry of valve leaflet motion and investigate its correlation with the functional symmetry of the valve. We hypothesize that an asymmetry in the valve leaflet motion will generate an asymmetry in the flow patterns, resulting in added local stress and forces on some of the leaflets. Two pair-wise leaflet symmetry scores are proposed based on diagonals of orthogonal projection matrices (DOPM) and dynamic time warping (DTW) techniques. The proposed symmetry score profiles are compared with fluid dynamic parameters (vorticity and velocity values) at the leaflet borders, obtained from valve-specific numerical simulations. Experiments on four cases including different tricuspid PHV designs yielded promising results, with DTW scores showing good coherence with respect to the simulations, which confirms our hypothesis. The established link between visual and functional symmetry opens the door for durability estimation of prosthetic heart valves using computer vision techniques. / Graduate

The evaluation of prosthetic valves can provide a unique challenge, and a thoughtful approach is required. High output states like anemia should be kept in the differential when evaluating elevated gradients across prosthetic valves. We present the case of a 69-year-old man with a Starr-Edwards prosthetic aortic valve who presented with symptoms of congestive heart failure and high transvalvular pressure gradients. These symptoms indicate a potential prosthetic valve stenosis. His laboratory evaluation results were consistent with valve-related hemolysis. Resolving his anemia led to a resolution of the symptoms and lowered the pressure gradient on follow-up.

Congenital and developmental limb deformities in canines are rare and can occur as a genetic disorder or be caused by extrinsic factors. Without surgery to correct the deformity, conservative management can be implemented to manage exercise and restrict high-intensity activity of the canine. However, any alteration to the normal gait and locomotive biomechanics of a canine can have significant long-term effects on the musculoskeletal health and quality of life of the canine. To improve quality of life and provide an alternative and more cost-effective approach to surgery, a custom prosthetic was designed and developed for a canine born with a congenital right forelimb deformity. Since canine prosthetics that are currently on the market are limited and expensive, the goal of this thesis was to create a durable and inexpensive prosthetic to stabilize the gait of a canine. A 1-year-old German Shepherd was the single subject of this research project. The major results indicated that the custom-designed, 3D printed prosthetic parts, which included the foot and the body of the prosthetic, were strong enough to withstand the high-impact forces and stresses experienced during the gait of a canine. The results also indicated that the prosthetic was comfortable and did not cause any pain or discomfort to the canine, as well as the prosthetic leg and foot being the correct length to stabilize the gait of the canine and redistribute the body weight of the tripod canine to that of a tetrapod canine. This study also developed and outlined a feasible fabrication process that could be repeated and used to produce other custom prosthetics for canines with rare congenital or development limb deformities as an alternative to surgery. In a future study, fatigue testing, tensile testing, and impact testing should be performed to determine the failure points. Fatigue testing is a critical factor in determining failure of a part.

No description available.

This manuscript will explore the intersection of perceived disability due to limb loss and self-identity. The research is centered around the work in the Limbitless Solutions laboratory, where clinical research is providing children with customized prostheses. This research applies a focus on how customization can lead to positive identity construction. By facilitating active engagement in the design process a stronger connection is formed between the participant and their prosthetic device.

No description available.

In the context of the rapid development of the research in the biosystem structure materials domain, a representative direction shows the analysis of the behavior of these materials. This direction of research requires the use of various means and methods for theoretical and experimental measuring and evaluating. PhD thesis "Methods and means for analyzing the behavior of biosystems structure materials" shall be given precedence in this area of research, aimed at studying the behavior of polymeric materials and composites biosystems structure and in particular the skeletal structure biosystem. Therefore, it is developed a specific method of research based on the development of theoretical models for the prediction of the mechanical, thermal and machinability properties of these materials. There are used Moldflow, Solidworks and Ansys software types. In order to validate the theoretical research were designed and conducted experimental research on the mechanical properties and the behavior of the polymeric biomaterials represented by ABS, UHMWPE, HDPE, PA, PC, PET, PP, PP_GF-30% and composite materials with polymeric thermoplastic matrixes from the skeletal biosystem¿s structure. In order to analyze the theoretical and experimental correlations, the experimental data were processed using the statistical analysis software programs SPSS v17, v8 Origin, Palisade Decision Tools. In conclusion, the thesis represents a technic, scientific and efficient support for analyzing the behavior of the new polymeric and composite materials from the biosystem structure. / Mitu, LG. (2014). Methods and techniques for bio-system's materials behaviour analysis [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/35445