Finite Element Analysis of Conventional Fixation and 3D-Printed Scaffold Integration for Treating Large...

Area of Science:

• Biomechanical Engineering
• Orthopedic Surgery
• Materials Science

Background:

• Large osseous defects pose significant challenges in orthopedic treatment.
• Conventional fixation methods often struggle with mechanical stability and promoting optimal bone regeneration.

Purpose of the Study:

• To biomechanically evaluate conventional and 3D-printed scaffold-augmented fixation for large femoral defects.
• To compare the efficacy of different scaffold designs and fixation techniques.

Main Methods:

• Finite element analysis of four conventional fixation methods (single plate, intramedullary nail, plate and nail, double plate).
• Integration of three porous Ti-6Al-4V scaffold designs (Weaire-Phelan, Diamond, Voronoi) with 70% porosity.
• Simulation of peak physiological loading for a 106 kg patient.

Main Results:

• Single-implant methods were insufficient, failing at 20-90% of physiological load with poor osteogenic callus formation (<16%).
• Combined conventional methods (plate and nail, double plate) withstood 100% load and promoted >95% osteogenic callus.
• 3D-printed scaffolds augmented single implants, enabling 100% load capacity and >90% osteogenic callus.
• Plate and nail fixation with a scaffold was most robust, reducing implant stress to ~140 MPa and achieving >99% osteogenic callus.

Conclusions:

• 3D-printed scaffolds significantly improve mechanical stability and osteogenic potential for large bone defect fixation.
• Scaffold augmentation transforms insufficient single-implant constructs into robust solutions.
• The plate and nail fixation combined with a 3D-printed scaffold represents a superior strategy for treating large osseous defects.