Joint replacement surgery and the innate immune system.
Total joint replacement is a highly successful, cost-effective surgical procedure that relieves pain and improves function for patients with end-stage arthritis. The most commonly used materials for modern joint replacements include metal alloys such as cobalt chrome and titanium alloys, polymers including polymethylmethacrylate and polyethylene, and ceramics. Implantation of a joint prosthesis incites an acute inflammatory reaction that is regulated by the innate immune system, a preprogrammed non-antigen specific biological response composed of cells, proteins, and other factors. This "frontline" immune mechanism was originally designed to combat invading microorganisms, but now responds to both pathogen-associated molecular patterns or PAMPS (by-products from microorganisms), and damage associated molecular patterns or DAMPS (molecular by-products from cells), via pattern recognition receptors (PRRs). In this way, potentially injurious stimuli that might disrupt the normal homeostatic regulatory mechanisms of the organism are efficiently dealt with, ensuring the survival of the host. Initial surgical implantation of the joint replacement, as well as ongoing generation of wear debris and byproducts during usage of the joint, activates the innate immune system. Understanding and potentially modulating these events may lead to improved function and increased longevity of joint replacements in the future.
Department of Orthopaedic Surgery Stanford University Medical Center Redwood City, CA.
Stuart B
SB
Goodman
Department of Clinical Medicine, University of Helsinki and ORTON Orthopaedic Hospital of the Invalid Foundation, Helsinki, Finland.
Yrjo T
YT
Konttinen
Department of Orthopaedic Surgery Yamagata University School of Medicine Yamagata, Japan.
Michiaki
M
Takagi
D019643:Arthroplasty, Replacement; D006801:Humans; D007113:Immunity, Innate / Q000502:physiology*; D007595:Joint Prosthesis; D053472:Nod Signaling Adaptor Proteins / Q000378:metabolism; D011474:Prosthesis Design; D011475:Prosthesis Failure; D051193:Toll-Like Receptors / Q000378:metabolism
D053472:Nod Signaling Adaptor Proteins; D051193:Toll-Like Receptors