Bioabsorbable magnesium-based bulk metallic glass composite (BMGC) for improved medial opening wedge high tibial osteotomy in knee osteoarthritis

Osteoarthritis is a widespread and debilitating condition, particularly affecting the medial compartment of knee joint due to varus knee deformities. Medial opening wedge high tibial osteotomy (MOWHTO) has emerged as an effective treatment, but it comes with challenges like fractures, correction loss, and nonunion, leading to unsatisfactory results in up to 26 % of patients. In response, our study explores the potential of a bioabsorbable magnesium-based bulk metallic glass composite (Mg67Zn28Ca5 BMGC) enriched with molybdenum particles as an innovative solution for MOWHTO. Our comprehensive study includes composite fabrication, mechanical property evaluations, in vitro degradation tests, cell viability assessments, cell migration assays, calcium deposition analyses, and osteoblast differentiation investigations. In vivo experiments were commenced for assessing biological effects and bone growth of the Mg67Zn28Ca5 BMGC in an animal model. Finite element analysis was utilized for assessing the mechanical impact of the composite wedge in human MOWHTO. The findings indicate that the Mg67Zn28Ca5 BMGC closely matches human cortical bone's mechanical properties, with controlled degradation and superior cellular responses. In vivo experiments reveal progressive degradation and bone integration. Finite element analysis confirms the composite's mechanical effectiveness in MOWHTO. In conclusion, our research introduces an innovative Mg67Zn28Ca5 BMGC enriched with molybdenum particles, showing promising mechanical and degradation characteristics. It has the potential to improve MOWHTO surgeries by matching cortical bone properties, controlled degradation, and promoting beneficial ion release for bone health. Successful tissue integration suggests suitability for high tibial osteotomy surgeries, offering hope for better outcomes in knee osteoarthritis patients. This article focuses on meeting the advantages of a novel magnesium-based BMGC with the clinical unmet need of MOWHTO surgeries. If properly developed, the results of this article have significant potential of translation to other temporary orthopedic implants under load-bearing conditions.