Cole JB, Florez JC: Genetics of diabetes mellitus and diabetes complications. Nat Rev Nephrol 16: 377, 2020.
Savelieff MG, Callaghan BC, Feldman EL: The emerging role of dyslipidemia in diabetic microvascular complications. Curr Opin Endocrinol Diabetes Obes 27: 115, 2020.
Venkatesan SK: Classification of diabetes mellitus: a review. Int J Diabetes Manage 1: 20, 2021.
Centers for Disease Control and Prevention: Division of diabetes translation at a glance. Available at: https://www.cdc.gov/chronicdisease/resources/publications/aag/diabetes.htm. Accessed February 5, 2022.
Pastore D, Deja-Simoni A, De Stefano A, et al: Risk factors for diabetic foot ulcers: an Albanian retrospective study of inpatients with type 2 diabetes. Eur Rev Med Pharmacol Sci 26: 558, 2022.
Abbott CA, Chatwin KE, Rajbhandari SM, et al: Site-specific, critical threshold barefoot peak plantar pressure associated with diabetic foot ulcer history: a novel approach to determine DFU risk in the clinical setting. Medicina 58: 166, 2022.
López-Moral M, Molines-Barroso RJ, García-Morales E, et al: Predictive values of foot plantar pressure assessment in patients with midfoot deformity secondary to Charcot neuroarthropathy. Diabetes Res Clin Pract 175: 108795, 2021.
Chuter VH, Spink MJ, David M, et al: Clinical foot measurements as a proxy for plantar pressure testing in people with diabetes. J Foot Ankle Res 14: 1, 2021.
Jarl G, van Netten JJ, Lazzarini PA, et al: Should weight-bearing activity be reduced during healing of plantar diabetic foot ulcers, even when using appropriate offloading devices? Diabetes Res Clin Pract 175: 108733, 2021.
Collings R, Freeman J, Latour J, et al: Footwear and insole design features for offloading the diabetic at risk foot—a systematic review and meta-analyses. Endocrinol Diabetes Metab 4: e00132, 2020.
Brognara L, Mazzotti A, Di Martino A, et al: Wearable sensor for assessing gait and postural alterations in patients with diabetes: a scoping review. Medicina 57: 1145, 2021.
Shaulian H, Gefen A, Solomonow-Avnon D, et al: Finite element-based method for determining an optimal offloading design for treating and preventing heel ulcers. Comput Biol Med 131: 104261, 2021.
Telfer S, Woodburn J, Collier A, et al: Virtually optimized insoles for offloading the diabetic foot: a randomized crossover study. J Biomech 60: 157, 2017.
Birke JA, Pavich MA, Patout CA Jr, et al: Comparison of forefoot ulcer healing using alternative off-loading methods in patients with diabetes mellitus. Adv Skin Wound Care 15: 210, 2002.
D’Amico M, Kinel E, Roncoletta P, et al: Data-driven CAD-CAM vs traditional total contact custom insoles: a novel quantitative-statistical framework for the evaluation of insoles offloading performance in diabetic foot. PloS One 16: e0247915, 2021.
Mandolini M, Brunzini A, Manieri S, et al: “Foot Plantar Pressure Offloading: How to Select the Right Material for a Custom Made Insole,” in Proceedings of the 21st International Conference on Engineering Design (ICED 17) Vol 1: Resource Sensitive Design, Design Research Applications and Case Studies, Vancouver, Canada, August 21–25, 2017.
Paulick PE, Pham AL, Bachman M, et al: Combining dynamic foot scanning and additive manufacturing for the production of insoles: a case study. Res J Textile Apparel 18: 1, 2014.
Armstrong DG, Short B, Espensen EH, et al: Technique for fabrication of an “instant total-contact cast” for treatment of neuropathic diabetic foot ulcers. JAPMA 92: 405, 2002.
Gatt A, Formosa C, Chockalingam N: The application of generic CAD/CAM systems for the design and manufacture of foot orthoses. Foot Ankle Online J 9: 5, 2016.
Ki SW, Leung AKL, Li ANM. Comparison of plantar pressure distribution patterns between foot orthoses provided by the CAD-CAM and foam impression methods. Prosthet Orthot Int 32: 356, 2008.
Udiljak T, Obrovac K, Ištef I: CAD/CAM system for insole production. Commun Sci Lett Univ Zilina 2: 70, 2000.
Hochste Healthcare Private Ltd: Foot ulcer footwear. Available at: https://www.indiamart.com/hochstehealthcare/foot-ulcer-footwear.html. Accessed May 8, 2022.
Davia-Aracil M, Hinojo-Pérez JJ, Jimeno-Morenilla A, et al: 3D printing of functional anatomical insoles. Comput Ind 95: 38, 2018.
Paton JS, Stenhouse EA, Bruce G, et al: A comparison of customised and prefabricated insoles to reduce risk factors for neuropathic diabetic foot ulceration: a participant-blinded randomised controlled trial. J Foot Ankle Res 5: 31, 2012.
Twitter. [Online]. Available at: https://twitter.com/lewihe. Accessed May 3, 2022.
Nouman M, Dissaneewate T, Leelasamran W, et al: The insole materials influence the plantar pressure distributions in diabetic foot with neuropathy during different walking activities. Gait Posture 74: 154, 2019.
Parker DJ, Nuttall GH, Bray N, et al: A randomized controlled trial and cost-consequence analysis of traditional and digital foot orthoses supply chains in a National Health Service Setting: application to feet at risk of diabetic plantar ulceration. J Foot Ankle Res 12: 1, 2019.
Waaijman R, De Haart M, Arts ML, et al: Risk factors for plantar foot ulcer recurrence in neuropathic diabetic patients. Diabetes Care 37: 1697, 2014.
Preece SJ, Chapman JD, Braunstein B, et al: Optimisation of rocker sole footwear for prevention of first plantar ulcer: comparison of group-optimised and individually-selected footwear designs. J Foot Ankle Res 10: 27, 2017.
Korada H, Maiya A, Rao SK, et al: Effectiveness of customized insoles on maximum plantar pressure in diabetic foot syndrome: a systematic review. Diabetes Metab Syndr 14: 1093, 2020.
Jafarzadeh E, Soheilifard R, Ehsani-Seresht A: Design optimization procedure for an orthopedic insole having a continuously variable stiffness/shape to reduce the plantar pressure in the foot of a diabetic patient. Med Eng Phys 98: 44, 2021.
Haris F, Liau BY, Jan YK, et al: A review of the plantar pressure distribution effects from ınsole materials and at different walking speeds. Appl Sci 11: 11851, 2021.
Peker A, Aydin L, Kucuk S, et al: Additive manufacturing and biomechanical validation of a patient-specific diabetic insole. Polym Adv Technol 31: 988, 2020.
Adelnia H, Bidsorkhi HC, Ismail AF, et al: Gas permeability and permselectivity properties of ethylene vinyl acetate/sepiolite mixed matrix membranes. Sep Purif Technol 146, 351, 2015.
Lou C, Wang S, Liang T, et al: A graphene-based flexible pressure sensor with applications to plantar pressure measurement and gait analysis. Materials 10: 1068, 2017.
Nosov NV, Zyabochkina AP: “Designing the Structure of and a Fabrication Process for a Corrective Insole in CAD/CAE/CAM Systems,” in IOP Conference Series: Materials Science and Engineering 709: 022105, 2020.
Jandova S, Mendricky R: Benefits of 3D printed and customized anatomical footwear insoles for plantar pressure distribution. 3D Print Addit Manuf 9: 547, 2022.
Mariani B, Rouhani H, Crevoisier X, et al: Quantitative estimation of foot-flat and stance phase of gait using foot-worn inertial sensors. Gait Posture 37: 229, 2913.
Watasuntonpong P, Pimsarn M, Tantrapiwat A: Dynamic feed rate in multiple independent spindles CNC milling machine for orthotic insole manufacturing. Int J Innov Comput Inform Control 15: 2149, 2019.
Tumbleston JR, Shirvanyants D, Ermoshkin N, et al: Continuous liquid interface production of 3D objects. Science 347: 1349, 2015.
Background: Muscle disorders may cause a change in plantar pressures by the misalignment on the foot during gait phases. Therefore, corns or calluses develop at the plantar regions, and diabetic foot ulcers follow for severe cases, although it can be prevented and even treated by podiatric approaches with patient-specific therapeutic insoles and footwear. Although the importance of a threshold value of 200 kPa in peak plantar pressure reduction has been highlighted as a standard to prevent reulceration in the diabetic foot, it may not be possible to ensure this pressure reduction for each patient.
Methods: In this study, three types of ethylene-vinyl acetate have been used to optimize the off-loading performance for predetermined early-stage diabetic foot ulcer scenarios by means of baropodometric plantar pressure analyses and finite element method for each gait phase.
Results: The total cost of the manufacturing for this study was reduced to $10.26 and it was performed in 24.6 minutes. In addition, the off-loaded pressure was increased by 2.3 times and the volume of the off-loading geometry was increased 8.12 times based on the foam polymer used.
Conclusions: Consequently, improved off-loading was obtained and a standard was proposed for the first time to calculate the off-loading performance before manufacturing of the therapeutic insole model to ensure a better recovery period.