ABSTRACT
ObjectiveTo review the classification of orthopedic insoles, common techniques of 3D printing orthopedic insoles, common materials and their application for flatfoot. MethodsLiteratures were retrieved from PubMed, Web of Science, CNKI and Wanfang Data from 2012 to 2022, and the relevant contents were summarized. ResultsA total of ten studies were finally included, from 5 countries, involving 290 participants, which published from 2019 to 2022. Orthotic insoles were classified as prefabricated, semi-custom, and custom, while custom ones were classified as traditional custom and 3D printed custom. 3D printed orthotic insoles were often made with selective laser sintering, fused deposition modeling (FDM) and PolyJet printing technologies, and commonly used materials included ethylene-vinyl acetate (EVA), polylactic acid, thermoplastic polyurethane, polyamide, and polypropylene. For flatfoot, 3D printed orthotic insoles could improve plantar pressure, relieve foot pain and the combined use of insole posting could control rearfoot valgus. Conclusion3D printed custom insoles can be made more efficiently and accurately than traditional custom insoles. The printing technologies and materials often chosen for 3D printed orthotic insoles are mainly FDM and EVA. 3D printed orthotic insoles is effective on plantar pressure, comfort and foot movement function of flatfoot.