Normal usage of total joint replacements results in the production of wear debris and other byproducts. In particular, polyethylene particles are heavily involved in the stimulation of local and systemic biological reactions resulting in chronic inflammation, periprosthetic bone resorption (osteolysis), and eventually implant loosening. As sentinels of the innate immune system, cells of the monocyte/macrophage lineage initiate the inflammatory cascade that lead to osteolysis. The biological processes involved are complex, based on the unique properties of the monocytes/macrophages, including sensing, chemotaxis, phagocytosis, and adaptive stimulation. The interaction with wear debris triggers the release of pro-inflammatory factors such as tumor necrosis factor-α, interleukin-1, and others; pro-osteoclastic factors such as RANKL; and chemokines such as MCP-1 and MIP-1, all of which are crucial to the recruitment, migration, differentiation, and ultimately activation of bone-resorbing osteoclasts. In parallel, other distinct macrophage populations inhibit inflammation and mitigate its consequences on the bone-implant interface. Here, the role of the monocyte/macrophage cell lineage in the initiation and maintenance of the host inflammatory response to wear debris and subsequent periprosthetic osteolysis is presented.

Department of Immunology Faculty of Medicine and Dentistry Palacky University Olomouc Czech Republic; Department of Orthopaedics Teaching Hospital Faculty of Medicine and Dentistry Palacky University Olomouc Czech Republic

Department of Medicine Institute of Clinical Medicine Helsinki University Central Hospital 00029 HUS Finland; Orthopaedic Research Laboratories Department of Orthopaedic Surgery Stanford University School of Medicine Stanford CA USA

Department of Orthopaedic Surgery Yamagata University Faculty of Medicine Iida Nishi 2 2 2 Yamagata 990 9585 Japan

Department of Orthopaedics Teaching Hospital Faculty of Medicine and Dentistry Palacky University Olomouc Czech Republic; Department of Orthopaedics ORTON Orthopaedic Hospital 00280 Helsinki Finland; COXA Hospital for Joint Replacement 33520 Tampere Finland

Laboratoire de Biomecanique et Biomateriaux Osteo Articulaires UMR CNRS 7052 Faculte de Medecine Universite Paris 7 Paris France; Department of Orthopaedic Surgery European Teaching Hospital Assistance Publique Hopitaux de Paris

Orthopaedic Research Laboratories Department of Orthopaedic Surgery Stanford University School of Medicine Stanford CA USA

References provided by Crossref.org

Periprosthetic Osteolysis: Mechanisms, Prevention and Treatment