Method of computational design for additive manufacturing of hip endoprosthesis based on basic-cell concept

Area of Science:

• Biomedical Engineering
• Materials Science
• Computational Mechanics

Background:

• Conventional hip replacements face limitations in customization and long-term performance.
• Additive manufacturing offers potential for complex, patient-specific medical devices with tailored porosity.
• Optimized porous structures are crucial for cell proliferation, bone remodeling, and mechanical property adjustment.

Purpose of the Study:

• To develop and evaluate a novel computational method for designing complex hip endoprostheses.
• To utilize a basic-cell concept combined with topology optimization for irregular structure design.
• To assess the impact of the proposed method on implant structural integrity and material efficiency.

Main Methods:

• A computational method combining topology optimization and structural design algorithms was employed.
• A cube with spheroid pores served as the basic cell, with variable porosity and mechanical properties.
• Bending and compression analyses were performed on cylindrical structures and two hip implant designs.

Main Results:

• The basic-cell geometry significantly influenced the stress-strain state of the structures.
• Implant volumes were reduced by 9% and 11% after optimization, with retained load-bearing capacity.
• Optimized implants exhibited altered internal structures, suggesting improved structural integrity with less material.

Conclusions:

• The novel computational method enables the design of hip endoprostheses with complex, functional porous structures.
• This approach facilitates the use of additive manufacturing for creating advanced medical implants.
• The method offers reduced design time and improved material efficiency for hip replacement devices.