Nanozyme-engineered liners for proactive prevention of wear particle-induced osteolysis

Wear particle-induced osteolysis (WPO), primarily caused by particles generated from implants under mechanical loading, remains a major barrier to the long-term success of prosthetic implants. Traditional strategies to address WPO have largely focused on reducing wear generation, rather than mitigating the immunostimulatory effects elicited by wear particles. However, the limited scope of mechanical enhancement and the inevitable generation of wear particles shift increasing attention toward biological improvements. Herein, we propose a "proactive preventive" strategy for liner design, aiming to effectively prevent WPO by simultaneously reducing the generation of wear particles and minimizing their immunostimulatory effects. To validate the feasibility of this strategy, we synthesize a model system by incorporating ceria nanozyme into ultra-high molecular weight polyethylene (UHMWPE), referred to as CZPE. Mechanical assessments demonstrate an approximately 32% reduction in wear particle production of CZPE compared with pristine UHMWPE. Moreover, CZPE particles elicit a markedly attenuated immune response compared to PE particles in a male murine model of WPO, including reduced macrophage-mediated inflammation and diminished intramedullary plasma cell infiltration. These effects contribute to a reduction in osteoclastic bone resorption and foreign body reactions. Leveraging these mechanical and biological advantages, our approach offers a promising implant design strategy for WPO prevention.