Additive manufacturing of person specific diabetic foot insoles with adjustable cushioning properties using TPMS lattice structures

Complications associated with diabetes are numerous, including foot problems which in extreme cases can lead to amputations. Current management involves the use of foam diabetic foot insoles (DFI) to provide cushioning, however load bearing capacity is limited, and designs often do not provide a comfortable or efficacious fit. This study aspires to resolve problems using digital fabrication workflows. The exploration of potential 3D scanning of anatomical data, parametric modelling, and additive manufacturing was created for a patient specific DFI. This demonstrated that patient scanning data provides means to create a custom fitting insole template, improving overall fit. Demonstrating the use of triply periodic minimal surface (TPMS) structures, fabricated in Thermoplastic Polyurethane (TPU), as cushioning structures, whereby unique lattice designs allow regionally tailored mechanical loading properties of the insole concept. The final insole realises a superior alternative to tradition DFI.