Proinflammatory cytokines and arthroscopic findings of patients withinternal derangement and osteoarthritis of the temporomandibular joint

This study investigated the correlations between the concentrations of proinflammatory cytokines in synovial fluid and the degree of synovitis on the one hand, and the degree of degeneration of articular cartilage on the other hand, in patients with internal derangement and osteoarthritis of the temporomandibular joint. We measured the concentrations of interleukin-1b (IL-1b), tumour necrosis factor-a (TNF-a), IL-6 and IL-8 in synovial fluid and the degree of arthroscopic synovitis and degeneration of articular cartilage in37 joints with internal derangement and osteoarthritis. The correlations between the concentration of each cytokine and the score of each arthroscopic feature were analysed statistically. The detection rates of IL-1b,TNF-a, IL-6 and IL-8 were 57%, 78%, 89% and 70%, respectively. There was a positive correlation between the IL-6 concentration and the synovitis score (P = 0.02). Measurement of IL-6 in synovial fluid might be useful as an indicator of the extent of synovitis.