New design of patient-specific, antimicrobial bioactive finger implants for durable functional reconstruction after amputation

The absence of even a single finger results in a major impairment in the hand function (precise grasping, grip power), therefore significantly affecting the social and professional life of victims who are frequently young people. Finger amputation is a surgical treatment for ~69.000 patients in the EU after traumatic injury, in which replantation microsurgery fails due to the severity of tissue damage. The surgical reconstruction is currently possible only via autograft transplantation, e.g. a toe-to-hand transfer, thus leading to foot impairment. Some motion functional restoration is also possible using a bone-anchored silicone prosthesis but without the sense revalidation. Our current research focuses on alternatives for surgical reconstruction by means of novel patient- -specific, durable, biomimetic, bioactive and antibacterial implants for reconstructing lost bone and joints. The implant design – and the improved micro(neuro) surgery (beyond the project) – will consist in the fast successful rehabilitation, including the soft-tissue related mobility, the implantation of state-of-the-art nerve conduits as well as the aesthetic appearance. Key issues for the long-term functionality of the biomaterial-based reconstruction of hard tissue are based on surgical demands, such as: (1) perfect integration of a bone-substituting metal with the surrounding bone tissue (a) with no signs of loosening due to stress shielding at the interface and (b) enhanced with protective activity against bacterial inflammation (antimicrobial properties and formation of vascularized bone tissue (ossification)) even months to years after the injury; (2) biomimetic finger joints based on non-wearing materials without ossification meant to prevent the loss of the motion function.