The infection burden associated with CIED implantation is increasing over time and is associated with prolonged hospital stays and high financial costs.

Background Highly crosslinked polyethylene (HXLPE) was introduced to reduce wear and osteolysis in total joint arthroplasty. While many studies report wear and osteolysis associated with HXLPE, analytical techniques, clinical study design and followup, HXLPE formulation and implant design characteristics, and patient populations differ substantially among investigations, complicating a unified perspective. Questions/purposes Literature on first-generation HXLPE was summarized. We systematically reviewed the radiographic wear data and incidence of osteolysis for HXLPE in hip and knee arthroplasty. Methods PubMed identified 391 studies; 28 met inclusion criteria for a weighted-averages analysis of two-dimensional femoral head penetration rates. To determine the incidence of osteolysis, we estimated a pooled odds ratio using a random-effects model.Results Weighted-averages analyses of femoral head penetration rates in HXLPE liners and conventional UHMWPE liners resulted, respectively, in a mean twodimensional linear penetration rate of 0.042 mm/year based on 28 studies (n = 1503 hips) and 0.137 mm/year based on 18 studies (n = 695 hips). The pooled odds ratio for the risk of osteolysis in HXLPE versus conventional liners was 0.13 (95% confidence interval, 0.06-0.27) among studies with minimum 5-year followup. We identified two clinical studies of HXLPE in TKA, preventing systematic analysis of outcomes. Conclusions HXLPE liner studies consistently report lower femoral head penetration and an 87% lower risk of osteolysis. Reduction in femoral head penetration or osteolysis risk is not established for large-diameter ([ 32 mm) metallic femoral heads or ceramic femoral heads of any size. Few studies document the clinical performance of HXLPE in knees.

An in vivo rat cage implant system was used to identify potential surface chemistries that prevent failure of implanted biomedical devices and prostheses by limiting monocyte adhesion and macrophage fusion into foreign-body giant cells while inducing adherent-macrophage apoptosis. Hydrophobic, hydrophilic, anionic, and cationic surfaces were used for implantation. Analysis of the exudate surrounding the materials revealed no differences between surfaces in the types or levels of cells present. Conversely, the proportion of adherent cells undergoing apoptosis was increased significantly on anionic and hydrophilic surfaces (46 ؎ 3.7 and 57 ؎ 5.0%, respectively) when compared with the polyethylene terephthalate base surface. Additionally, hydrophilic and anionic substrates provided decreased rates of monocyte͞macro-phage adhesion and fusion. These studies demonstrate that biomaterial-adherent cells undergo material-dependent apoptosis in vivo, rendering potentially harmful macrophages nonfunctional while the surrounding environment of the implant remains unaffected.