Magnesium-based alloys for bone regeneration and beyond: A review of advances and therapeutic prospects.

Background: Magnesium (Mg)-based alloys have gained significant attention as next-generation biodegradable biomaterials due to their bone-mimetic mechanical properties (elastic modulus: 35-45 GPa), biocompatibility, and ability to degrade in vivo without toxic byproducts. Objective: This review systematically evaluates recent advances in Mg-based alloys for biomedical applications, focusing on orthopedic implants, cardiovascular stents, and drug delivery systems, while identifying current challenges and future research directions. Methods: We conducted a comprehensive literature analysis of peer-reviewed studies (2019-2024) examining Mg alloy development, surface modification techniques, in vitro/in vivo performance, and clinical trial outcomes. Results: Key findings include: (1) Alloying innovations, particularly with rare-earth elements (e.g., in WE43) and nutrient elements (Zn, Ca), have yielded alloys with bone-mimetic mechanical properties (elastic modulus: 35-45 GPa; compressive yield strength: 150-250 MPa) and decelerated degradation rates via grain refinement and secondary phase formation; (2) Surface-modified Mg stents show improved endothelialization with 30-50 % reduced restenosis rates (3) Structurally engineered Mg-based scaffolds (e.g., via additive manufacturing); enable topological control over degradation through tailored porosity; (4) Drug-eluting Mg carriers achieve sustained release kinetics, leveraging degradation to simultaneously promote tissue regeneration and deliver therapeutics. However, rapid degradation (0.2-0.5 mm/year in physiological conditions) and hydrogen gas evolution remain critical challenges. Conclusion: Mg-based alloys show transformative potential for temporary medical implants. Future research should focus on: (1) advanced alloy design with rare-earth elements, (2) smart coating technologies, and (3) standardized long-term biocompatibility assessments to facilitate clinical translation.