Sclerostin Antibody Prevents Particle-Induced Implant Loosening by Stimulating Bone Formation and Inhibiting Bone Resorption in a Rat Model

Objective. To assess the ability of sclerostin antibody therapy to blunt the negative effects of polyethylene particles on implant fixation and peri-implant bone structure in a rat implant fixation model. Methods. Thirty-six adult male rats received intramedullary titanium implants; 12 rats received vehicle injections only (control), and 24 rats received intraarticular injections of lipopolysaccharide-doped polyethylene particles. Twelve of the rats that received particles also received sclerostin antibody treatment. The 3 groups of rats were maintained for 12 weeks in a pathogen-free environment, at which time mechanical, micro-computed tomography, and dynamic and static histomorphometry end points were assessed. Results. Sclerostin antibody treatment completely blocked the negative effect of the lipopolysaccharide-doped polyethylene particles on implant fixation and peri-implant bone volume by increasing the bone formation rate and depressing bone resorption. Conclusion. Anabolic agents targeting the Wnt signaling pathway are a promising new alternative for the prevention of periprosthetic osteolysis and aseptic loosening.