Finite Element Analysis of Bending Strength in Novel Architected Porous Fe-Mn Fracture Fixation Implants during the Bone Healing Period

This paper presents biodegradable load-bearing fracture fixation implants inspired by cortical bone porosity for metal additive manufacturing. Traditional materials like stainless steel and titanium need permanent implantation or revision surgery, while current biodegradable materials lack strength and degrade too slowly. We designed Triply Periodic Minimal Surface (TPMS)-based gyroid structures mimicking cortical bone, achieving minimal porosity for controlled degradation and sufficient bending strength. Fe-Mn implants with 5-15% porosity met United States Food and Drug Administration (USFDA) bending test criteria. Finite element analysis showed reduced cross-section implants maintained structural integrity at a 0.5 mm/year degradation rate during the 3-6 month healing period, demonstrating possible balance in structural strength and controlled degradation.