Date of Award
8-2024
Document Type
Thesis
Degree Name
Master of Science (MS)
Department
Bioengineering
Committee Chair/Advisor
Dr. John DesJardins
Committee Member
Dr. Jiro Nagatomi
Committee Member
Dr. Joseph Singapogu
Abstract
Approximately 78% of people with lower limb amputations are dissatisfied with the comfort of their prostheses (Quintero-Quiroz & Perez 2019). In the case of lower limb amputations, the residual limb tissue bears far more weight than it was before the amputation. The pressure put on the soft tissue of the residual limb causes discomfort (Brown et al. 2021). In previous work, custom inlays were created, which fit inside the prosthesis and offload pressure, with the goal of helping to increase the comfort and satisfaction of the prosthesis user (Brown et al. 2021). In this project, a benchtop prosthetic socket loading fixture was used to quantify the pressure distributions in a reproducible fashion. For this work, a fake residual limb was created and fitted into the prosthesis with the inlays. Static loads were applied, and socket interface pressures were measured.
Inlays were created, which fit into the indentions made in the socket of a lower limb prosthesis. The blanks had a smooth, solid exterior surface, while the pressure-offloading meta-material inlays had a triangular pattern cut into the surface. The pattern was intended to change the properties of the material and offload pressure, while the blanks were intended to mimic a standard socket and act as a control. A residual limb model was made using silicone to represent the soft tissue, and an ‘amputated’ foam bone to represent the bony anatomy. The blanks were placed into the socket, then pressure sensors were placed over the surface of the blanks. The fake residual limb was placed into the socket, and load was applied using an Instron. Pressure mapping data was collected via the pressure sensors. The blank inlays were replaced with the meta-material inlays, and the procedure was repeated, with data being collected once again with the pressure sensors. The pressure data from the blank inlays and the meta-material inlays were compared in order to determine if the meta-material inlays truly offloaded pressure within the socket.
The results demonstrated that the inlays worked to offload pressure in the socket under some circumstances. Although there were not clear patterns from one socket to another, there is the potential for the inlays to help some users achieve greater comfort with their transtibial prosthesis.
Quintero-Quiroz, C., & Pérez, V. Z. (2019). Materials for lower limb prosthetic and orthotic interfaces and sockets: Evolution and associated skin problems. Revista de la Facultad de Medicina, 67(1), 117-125.
Brown, N., Owen, M. K., Garland, A., DesJardins, J. D., & Fadel, G. M. (2021). Design of a single layer metamaterial for pressure offloading of transtibial amputees. Journal of Biomechanical Engineering, 143(5), 051001.
Owen, M. (2021). Design, Development, and Evaluation of Additively Manufactured Technologies for Use in Lower Limb Prostheses. Clemson University.
Recommended Citation
Hill, Sarah G., "A Benchtop Analysis of Pressure Offloading Associated With Custom Socket Inlays in Transtibial Prostheses" (2024). All Theses. 4374.
https://open.clemson.edu/all_theses/4374
Author ORCID Identifier
0000-0002-1342-8829