A new methodology for design and manufacturing of a customized silicone partial foot prosthesis using indirect additive manufacturing

The production of customized prostheses for the foot and ankle still relies on slow and laborious steps of the traditional plaster molding fabrication techniques. Additive manufacturing techniques where three-dimensional objects can be constructed directly based on the object's computer-aided-design data in a layerwise manner has opened the door to new opportunities for manufacturing of novel and personalized medical devices. The purpose of the present study was to develop a new methodology for design and manufacturing of a customized silicone partial foot prosthesis via an indirect additive manufacturing process. Furthermore, the biomechanics of gait of a subject with partial foot amputation wearing the custom silicone foot prosthesis manufactured by the indirect additive manufacturing was characterized, in comparison with a matched healthy participant. This study has confirmed the possibility of producing silicone partial foot prosthesis by indirect additive manufacturing procedure. The amputated subject reported total comfort using the custom prosthesis during walking, as well as cosmetic advantages. The prosthesis restored the foot geometry and normalized many of gait characteristics. The findings presented here contribute to introduce a proper understanding of biomechanics of walking after wearing silicone partial foot prosthesis and are useful for prosthetists and rehabilitation therapists when treating patients after partial foot amputation.