Post-traumatic Talus Avascular necrosis. Designing and additive manufacturing of talus implant as an alternative for leg amputation

Abstract This study presents the design and development of a meshed implant intended for talus replacement surgery. Our focus was on a young adult patient who had sustained severe damage to the talus, resulting in avascular necrosis (AVN) and subsequent bone collapse. This condition caused persistent and debilitating pain, leading the medical team to consider amputation of the left foot at the ankle level as a last resort. Instead, we proposed an innovative approach involving the fabrication of a patient-specific implant specifically designed for pan-talar fusion. The implant was created using selective laser melting technology, which allowed for precise and accurate construction of the unique mesh structure. To ensure its mechanical integrity, we conducted uniaxial compression experiments, which confirmed that the proposed structure met all essential mechanical requirements, including compressive loading. The patient underwent regular monitoring for a period of 12 months. The meshed implant exhibited excellent osteoconductive properties, as evidenced by the successful ingrowth of bone into the mesh pores, resulting in a fusion between the implant and the surrounding bones.