Metabolic behavior of the degradation products of magnesium alloys in bone tissue

Magnesium alloys are potentially revolutionary bone implant materials owing to their favorable mechanical properties, biocompatibility, and biodegradability. Although the in vivo and in vitro degradation behavior of Mg alloys have been extensively explored, only a few in vivo studies on the metabolic behavior of the degradation products of different elements are available. In this study, a Mg-2 wt. % Zn-0.5 wt. % Y-1 wt. % Nd-0.5 wt. % Zr (ZE21C) alloy was used to prepare suture anchors, which were implanted into the patellar ligament proximal tibia of rats. The metabolic behavior of magnesium, zinc, and neodymium in the degradation products in vivo was analyzed through SEM, EDS, micro-XRF, and western blotting. These results indicate that Mg was rapidly metabolized and absorbed. However, Zn and Nd exhibited slow metabolic rates and accumulated as degradation products. This is mainly because the microenvironment generated by degradation inhibits metabolism by affecting the expression of cation-permeable channel proteins. This study analyzed the degradation and metabolic behavior of Mg alloys and provides a reference for the biological application of Zn as an alloying element.