Structural Optimization of Magnesium Alloy Rib Claw and Evaluation of Its Mechanical Reliability In Vitro and In Vivo

Area of Science:

• Biomaterials Engineering
• Orthopedic Devices
• Materials Science

Background:

• Biodegradable magnesium alloys offer potential for orthopedic implants, but require structural optimization for mechanical reliability.
• Rib claws are crucial for thoracic fixation, demanding robust and biocompatible materials.

Purpose of the Study:

• To structurally optimize and evaluate the mechanical reliability of novel biodegradable JDBM magnesium alloy rib claws.
• To compare the performance of the optimized magnesium alloy rib claws against existing titanium designs.

Main Methods:

• Finite element analysis (FEA) for structural simulation and stress reduction.
• In vitro four-point bending tests (ASTM F382-compliant) to assess yield load.
• 24-week in vivo implantation study in Bama pigs to evaluate long-term mechanical integrity.

Main Results:

• The optimized Gen3 magnesium alloy rib claw design reduced maximum von Mises stress by 54.15% and equivalent strain by 54.4%.
• In vitro tests showed Gen3 magnesium claws had a significantly higher yield load (358 ± 21 N) than titanium claws (219 ± 16 N).
• The 24-week in vivo study confirmed no fractures, demonstrating excellent mechanical reliability.

Conclusions:

• The structurally optimized Gen3 magnesium alloy rib claw exhibits superior mechanical properties and reliability.
• These findings support the promising clinical application of biodegradable magnesium alloy rib claws in thoracic surgery.