Numerical and Experimental Study of a Lattice Structure for Orthopedic Applications

Area of Science:

• Biomaterials Engineering
• Orthopedic Surgery
• Additive Manufacturing

Background:

• Prosthetic reconstructions face complications due to implant material limitations and the need for bone integration.
• Current biomaterials lack sufficient strength for load-bearing implants.
• Additive manufacturing offers potential for creating complex, porous structures for bone ingrowth.

Purpose of the Study:

• To correlate prosthetic structure geometry, mechanical properties, and biological integration.
• To develop algorithms for designing endoprostheses that mimic bone structure and mechanical properties.
• To minimize structural weight of lattice endoprostheses without compromising strength.

Main Methods:

• Iterative algorithm augmentation by removing low-loaded ribs based on threshold stress.
• Application of the algorithm to initial and designed structures at various threshold stresses (10-20 MPa).
• Analysis of Pareto diagrams for stress and rib count; experimental validation via four-point bending tests.

Main Results:

• An optimized 'lightweight' structure was identified at a threshold stress of 17 MPa.
• The optimal structure featured a maximum stress of 147.48 MPa and 741 ribs.
• Additive manufacturing enabled the creation and testing of these novel prosthetic designs.

Conclusions:

• Algorithm-driven design can significantly reduce endoprosthesis weight while preserving mechanical integrity.
• Optimized lattice structures show promise for improved bone integration and reduced complications in prosthetic reconstructions.
• Additive manufacturing is a key technology for fabricating patient-specific, high-performance implants.