J Orthop Res. 2021 Nov 23. doi: 10.1002/jor.25230. Online ahead of print.
ABSTRACT
Metal on polyethylene (MoP) total hip arthroplasty prostheses are known to release metal debris. Basic science studies suggest that metal implants induce a pro-inflammatory response that ultimately chemoattracts leukocytes including macrophages and neutrophils to the surgical site. This raises concern of higher risk of infection with these prosthesis through the “trojan horse” mechanism by which neutrophils and macrophages transport intracellular pathogens from a remote site. This study compared the infection occurrence between MoP and ceramic on polyethylene (CoP) implants to determine if a higher infection rate in MoP is present. We reviewed a consecutive series of 6,052 CoP and 4,550 MoP primary total hip arthroplasty (THA) patients from 2015-2019. The occurrence of periprosthetic joint infection at two years was defined according to the 2018 ICM definition. Statistical analysis consisted of descriptive statistics, univariate analysis, and regression modeling. When compared to CoP, MoP patients were older, included more females, had a higher body mass index, and more commonly affected by comorbidities according to Elixhauser score. Total revisions were higher in the MoP group (3.19% vs 2.41%) The absolute incidence of PJI was higher in MoP (2.40% vs 1.64%). When we adjusted for confounding factors, MoP was found independently associated with a higher PJI risk. Despite MoP and CoP both being widely used for primary THA, we found a higher incidence of PJI in MoP patients. The association remained significant when controlled for possible confounders. We hypothesize that leukocyte recruitment to these implants may play a role and should be further investigated. This article is protected by copyright. All rights reserved.
PMID:34812555 | DOI:10.1002/jor.25230
