Aseptic Loosening of Total Hip Replacement

Abstract

Aseptic loosening is a major cause of failure of total hip arthroplasty. The adverse tissue response to prosthetic wear particles, with activation of cytokine and prostanoid production, contributes to bone loss around the implants. We have investigated the possibility that inducible nitric oxide synthase (iNOS) and cyclo-oxygenase-2 (COX-2) are expressed in macrophages in the pseudomembrane at the bone-implant interface, thereby contributing to the periprosthetic bone resorption. We also assessed whether peroxynitrite, a nitric oxide (NO)-derived oxidant associated with cellular injury, is generated in the membrane. Enzymatic activity of iNOS was measured using the arginine-citrulline assay technique and prostaglandin E 2 (PGE 2), as an indicator of COX-2 activity, was measured using an enzyme immunoassay. Cellular immunoreactivity for iNOS, nitrotyrosine (a marker of peroxynitrite-induced cellular injury) and COX-2 was assessed by quantitative peroxidase immunocytochemistry while immunofluorescence methods were used for subsequent co-localisation studies with CD68 + macrophages.

Early expression of cyclo-oxygenase-2 during sporadic colorectal carcinogenesis

“…The characteristics of this antibody have been previously described. 31,32 Immunohistochemistry A standard ABC method was used in this series. Briefly, tissue sections were dewaxed in xylene, rehydrated through graded alcohol to distilled water, and then immersed in 0·3 per cent hydrogen peroxide in methanol for 30 min to delete endogenous peroxidase.…”

PPARγ delivered by Ch‐GNPs onto titanium surfaces inhibits implant‐induced inflammation and induces bone mineralization of MC‐3T3E1 osteoblast‐like cells

“…Recently, COX‐2 has been detected in the pseudomembrane at the bone‐implant interface (Hukkanen et al. ). Furthermore, MMP‐2 has been implicated in bone resorption that results in loosening of prostheses (Oum'hamed et al.…”

Biomechanical evaluation of the helica femoral implant system using traditional and modified techniques

“…Complications include infection with or without septic loosening, aseptic loosening, implant subsidence, femoral fracture, coxofemoral luxation, femoral medullary infarction, pulmonary embolism, and sciatic neurapraxia. [5][6][7][8][9][10][11][12][13][14][15][16][17][18] Implant loosening can be classified as biologic (i.e., aseptic loosening) or mechanical. The biologic causes have not been fully elucidated; however, proposed mechanisms include stress shielding, cyclic mechanical loading, and macrophage/ cell mediated responses to wear debris.…”

“…Despite great therapeutic potential, complications with varying degrees of clinical importance occur with cemented and cementless fixation systems. Complications include infection with or without septic loosening, aseptic loosening, implant subsidence, femoral fracture, coxofemoral luxation, femoral medullary infarction, pulmonary embolism, and sciatic neurapraxia …”

“…Implant loosening can be classified as biologic (i.e., aseptic loosening) or mechanical. The biologic causes have not been fully elucidated; however, proposed mechanisms include stress shielding, cyclic mechanical loading, and macrophage/cell mediated responses to wear debris . Mechanical loosening is further divided into micro‐ and/or macromotion.…”