Role of cytokines in gonarthrosis and knee prosthesis aseptic loosening.

Cytokines, which have been demonstrated in synovial fluids during various joint diseases, play an important role in mediating synovial inflammation and in regulating the immune response of many inflammatory processes. We studied synovial fluid, serum, and synovial fragments obtained from 33 patients--10 affected by serious gonarthrosis re-quiring a prosthetic implant, 8 with knee prosthesis aseptic loosening, and (as controls) 15 affected by degenerative meniscopathies--to evaluate the degree of inflammation and level of interleukins (IL-2, IL-4, IL-6, IL-10) and interferon gamma secretion. Histological analysis revealed slightly more infiltration by inflammatory cells in the synovial tissue of patients with gonarthrosis and knee prosthesis aseptic loosening than in that of the control group, with a high prevalence of macrophages. Moreover, we observed enhanced production of the studied cytokines, especially in synovial fluid as compared to serum, indicating that in the pathological conditions examined the inflammatory events are mainly localized. Because the role of these cytokines is to modulate inflammation, better knowledge of the involvement of cells and their soluble mediators in articular damage could guide immunomodulating treatment.
(The Japanese Orthopaedic Association)