A multi-domain computational framework investigating the short- and long-term viability of bioabsorbable magnesium fixation for tibial fractures.

This study presents a multi-domain computational framework to investigate the long-term performance of permanent and bioabsorbable magnesium fixation devices in orthopaedic fracture applications. The framework integrates a coupled model for bone fracture healing and remodeling, with an enhanced surface-based corrosion model to predict the performance of bioabsorbable magnesium devices. It was found that plated fracture fixation enabled fracture healing outcomes compare to non-plated models by facilitating direct fracture healing.

Predicting localised corrosion and mechanical performance of a PEO surface modified rare earth magnesium alloy for implant use through in-silico modelling.

In this study, the influence of a plasma electrolytic oxidation (PEO) surface treatment on a medical-grade WE43-based magnesium alloy is examined through an experimental and computational framework that considers the effects of localised corrosion features and mechanical properties throughout the corrosion process. First, a comprehensive in-vitro immersion study was performed on WE43-based tensile specimens with and without PEO surface modification, which included fully automated spatial reconstruction of the phenomenological features of corrosion through micro-CT scanning, followed by uniaxial tensile testing. Then the experimental data of both unmodified and PEO-modified groups were used to calibrate parameters of a finite element-based surface corrosion model.

An enhanced phenomenological model to predict surface-based localised corrosion of magnesium alloys for medical use.

This study developed an enhanced phenomenological model for the predictions of surface-based localised corrosion of magnesium alloys for use in medical applications. The modelling framework extended previous surface-based approaches by considering the role of β-phase components throughout the material volume to better predict spatial and temporal aspects of surface-based corrosion in magnesium alloys. This enhanced surface-based corrosion model offers many advantages as it (i) captures multi-directional pitting, (ii) captures various pit morphologies, (iii) eliminates mesh sizing effects, (iv) reduces computational cost through custom time controls (v) offers control of pit sizing and (vi) produces corrosion rates that are independent of pitting parameter values.

Linking the effect of localised pitting corrosion with mechanical integrity of a rare earth magnesium alloy for implant use.

This study presents a computational framework that investigates the effect of localised surface-based corrosion on the mechanical performance of a magnesium-based alloy. A finite element-based phenomenological corrosion model was used to generate a wide range of corrosion profiles, with subsequent uniaxial tensile test simulations to predict the mechanical response to failure. The python-based detection framework provides detailed quantification of the spatial phenomenological features of corrosion, including a full geometric tracking of corroding surface.

A coupled computational framework for bone fracture healing and long-term remodelling: Investigating the role of internal fixation on bone fractures.

In this study, a coupled computational modelling framework for bone fracture repair is presented that enables predictions of both healing and remodelling phases of the fracture region and is used to investigate the role of an internal fixation plate on the long-term healing performance of a fracture tibia under a range of different conditions. It was found that introduction of a titanium plate allowed the tibia to undergo successful healing at higher loading conditions and fracture gaps, compared with the non-plated versions. While these plated cases showed faster rates of repair in the healing phase, their performance was substantially different once they entered the remodelling phase, with substantial regions of stress shielding predicted.