Abstract
Significant advances in science, engineering, technology, and medicine have changed how we approach, diagnose, treat, and manage patients. Design and diagnostic tools for amputees are limited. The most common approach to designing a lower limb prosthetic socket is artisan using plaster casting or moulding process by a prosthetist. This thesis presents an alternative approach for prosthetic socket design by integrating ultrasound imaging, photogrammetry and 3D modelling. With this approach, the prosthetist can be better informed of the patient’s physical and physiological conditions of the residual limb and design better sockets. This approach has been presented in major segments; the first segment focuses on data collection and processing of ultrasound images. It also covers a detailed discussion on the various methods available for collecting multi-modal data like medical images, internal and external volumetric data, and the available software tools to process them. The processed data is then combined to generate a composite 3D model for the prosthetist to analyse. The next segment covers the proposed socket attachment design considerations and concept selection. The function analysis design tool was used to break down the main goal into individual functions and derives the metrics required for the design to adhere. The socket design has been tested in a virtual design simulation environment using Fusion360 under various scenarios that it would experience in a day-to-day use based on the human gait cycle. The initial design had structural issues due to high-stress concentrations at the joints. Based on the initial analysis, the socket design has undergone further iteration to address this concern and attempted to reduce the stress level to increase the safety factor. The safety of the design has been further analysed by subjecting it to a failure mode and effect analysis. This analysis identified several potential pathways for failure. This thesis also presents additional risk reduction measures to reduce those risks. In summary, the use of ultrasound imaging modality to generate a composite image of the stump has proven to be effective, while leaving some room for improvement in terms of sophisticated image analysis tools and visualisation to aid prosthetist. Derived design drivers from the geometrical and physiological data extracted from multi-modal data guide the process of designing a better lead to a better-fitted socket design. Keywords: Ultrasound Imaging; Data Processing; 3D Modelling; Prosthetic Socket Modification; Transtibial Prostheses; Surface Modelling