Modular Prosthesis Design for Additive Manufacturing

This article presents a methodology for the design and production of custom prostheses for complex surgical interventions on long bones due to oncological surgical treatment. This type of intervention considers the complete or partial removal of bone tissue that might be affected by bone tumors. In this scenario it is important to limit the loss of functionality of the patients’ joints. Accordingly, it is important to salvage, whenever possible, the original articulation surfaces of the joints; nevertheless, a complete evaluation of the tumor extension and of the state of bone tissue might be difficult to be performed in the preparation phase. The article presents an approach for geometrical modelling of a modular prosthesis for long bones, that leaves the surgeon free to tailor the resection according to their feedback in the operating theatre. Specifically, the devised methodology allows to salvage part of the original bone by switching modules of the prosthesis. The dissertation is tackled from a technical perspective, taking into account the constraints and key features that need to be considered in the design and production of a long bone prosthesis via additive manufacturing technologies. The methodology is presented with reference to a complex custom prosthesis design that was carried out with the support of T3Ddy’s - Personalized pediatrics by inTegrating 3D aDvanced technologies research laboratory.