Development of a 3D-printed shell lattice midsole for diabetic foot shoe

Abstract

This study aims to support diabetic foot treatment by introducing a customized offloading midsole specifically designed for neuropathic ulcers, one of the most common complications of diabetes. The goal is to explore a personalized, mechanically efficient, and low-cost solution that ensures optimal redistribution of plantar pressure.

A parametric design methodology based on sinusoidal shell lattice structures is developed. These geometries allow for structural adaptation by adjusting key design variables such as amplitude, cut out radius, and shell thickness. Finite element simulations are used to assess the mechanical behaviour of multiple cell configurations, followed by experimental validation using FDM 3D-printed samples. A prototype midsole is produced by mapping a distribution of variable-thickness cells onto an idealized plantar pressure pattern. Its mechanical performance is evaluated through compression testing using a foot-shaped stamp.

Results confirm the feasibility of achieving zoned stiffness distribution through additive manufacturing. The selected final configuration strikes a balance between structural integrity and deformability. Simulated results closely match experimental data, supporting the viability of the method for developing offload-sensitive midsoles. Unlike traditional foam-based designs, this approach enables a more continuous and precise modulation of mechanical response across the plantar surface.