Surface Engineering of Nano Magnesium Alloys for Orthopedic Implants: A Systematic Review of Strategies to Mitigate Corrosion and Promote Bone Regeneration

Yogesh Subhash Chaudhari¹Manisha Yogesh Chaudhari²Amol Gholap³Mohammad Intakhab Alam⁴Mohammad Khalid⁵Thomas Jay Webster^6,7,8*Gowri Sundaram Sundaram⁹Md. Faiyazuddin¹⁰

• ¹Hiranandani College of Pharmacy, Maharashtra, India
• ²Patil University School of Pharmacy, Maharashtra, India
• ³St. John Institute of Pharmacy and Research, Maharashtra, India
• ⁴Jazan University Hospital, Jazan Univeristy, Jazan, Saudi Arabia
• ⁵University of Glasgow, Glasgow, Scotland, United Kingdom
• ⁶Interstellar therapeutics, Boston, United States
• ⁷Brown University, Providence, Rhode Island, United States
• ⁸Hebei University of Technology, Beichen District, Tianjin Municipality, China
• ⁹Bharathidasan University, Tamilnadu, India
• ¹⁰Saveetha Medical College & Hospital, Chennai, Tamil Nadu, India

Magnesium (Mg) alloys are transformative candidates for biodegradable orthopedic implants due to their bone-mimetic elastic modulus (10-30 GPa), biocompatibility, and osteogenic properties. However, rapid corrosion (>2 mm/year) and hydrogen gas evolution (0.1-0.3 mL/cm²/day) in physiological environments hinder clinical adoption. This systematic review, leveraging insights from seven databases (PubMed®, Embase, Web of Science™, Scopus®, IEEE Xplore, FSTA, and Google Scholar), critically evaluates surface engineering innovations that address these challenges. Key findings demonstrate that micro-arc oxidation (MAO) reduces corrosion rates by 60% (0.3-0.8 mm/year) through ceramic oxide layers, while hydroxyapatite (HA) coatings further enhance osteoconductivity (0.25 mm/year). NanoscaleMgO not only promotes osteoblast adhesion (40% increase) and collagen synthesis but also reduces bacterial colonization by 78% via surface energy modulation, eliminating antibiotic dependency. Advanced strategies like hybrid coatings (e.g., zwitterionic polymers) and alloying with Zn/Ca/Sr synergistically improve mechanical strength (up to 380 MPa), degradation control (0.1-0.5 mm/year), and angiogenesis via Mg²⁺-mediated VEGF upregulation. Emerging trends such as 4D bioprinting of pH-responsive Mg scaffolds and patient-specific implants highlight the shift toward dynamic, personalized solutions. Despite progress, challenges persist in synchronizing degradation with bone healing timelines, particularly in osteoporotic or diabetic patients. This review underscores the paradigm shift toward nano surface engineering, positioning Mg alloys as multifunctional platforms for nextgeneration orthopedic implants, while advocating for interdisciplinary collaboration to bridge translational gaps.