Synovial-fluid

Tuberculosis [TB] of the appendicular skeleton is an uncommon infection caused by the tuberculous bacilli and constitutes only 1-3% of all tuberculosis infections. MR imaging features of tuberculous arthritis include bone marrow oedema, cortical erosions, synovitis, joint effusion, tenosynovitis, soft tissue collections, and myositis. These imaging features are at times non-specific, but in the correct clinical context help in diagnosis of tuberculosis. We present the various pathological manifestations of TB arthritis involving the different joints of appendicular skeleton and discuss their MR imaging appearances.

Lubrication of mammalian joints is mediated by lubricin, a product of megakaryocyte stimulating factor gene (MSF; GenBank accession #U70136) expression. Lubricin (M(r) approximately 240 kDa) is a mucinous glycoprotein which is 50% (w/w) post-translationally modified with beta(1-3)Gal-GalNAc incompletely capped with NeuAc, and lubricates apposed cartilaginous surfaces in the boundary mode through an unknown mechanism. Both bovine and human lubricin were purified from synovial fluid and digested with recombinant glycosidases. Released oligosaccharides were identified and quantified by fluorophore assisted carbohydrate electrophoresis (FACE). Corresponding digests of human lubricin were also assayed in a friction apparatus oscillating latex rubber against polished glass at a pressure of 0.35 x 10(6) N/m(2) and the coefficient of friction (mu) was measured. Digestion with alpha2,3-neuraminidase decreased lubricating ability by 19.3%. Partial removal of beta(1-3)Gal-GalNAc moieties by en...

The aim of this study was to compare proinflammatory cytokine levels between successful cases and unsuccessful cases of arthrocentesis in patients with internal derangement of the temporomandibular joint (TMJ).This study involved 73 joints judged as successful and 30 judged as unsuccessful of 103 joints in 100 patients diagnosed with internal derangement of the TMJ and who underwent arthrocentesis. The diluted synovial fluid before undergoing arthrocentesis was aspirated from the superior joint space. The concentrations of interleukin (IL)-1β, tumor necrosis factor-α, IL-6, and IL-8 were measured using an enzyme-linked immunosorbent assay. The differences in the detection rate and concentration of each cytokine between successful cases and unsuccessful cases were analyzed statistically.There was a statistically significant difference between successful cases (72.2%) and unsuccessful cases (95.5%) in the detection ratio of IL-6 (P < .05). There was a statistically significant difference between successful cases (0.017 pg/100 μg protein) and unsuccessful cases (0.046 pg/100 μg protein) in the concentration of IL-1β (P < .05).It has been shown that the presence of IL-1β and IL-6 in synovial fluid may be indicators of possible unsuccessful treatment following arthrocentesis for internal derangement of the TMJ.

The synovial fluid (SF) of joints normally functions as a biological lubricant, providing low-friction and low-wear properties to articulating cartilage surfaces through the putative contributions of proteoglycan 4 (PRG4), hyaluronic acid (HA), and surface active phospholipids (SAPL). These lubricants are secreted by chondrocytes in articular cartilage and synoviocytes in synovium, and concentrated in the synovial space by the semi-permeable synovial lining. A deficiency in this lubricating system may contribute to the erosion of articulating cartilage surfaces in conditions of arthritis. A quantitative intercompartmental model was developed to predict in vivo SF lubricant concentration in the human knee joint. The model consists of a SF compartment that (a) is lined by cells of appropriate types, (b) is bound by a semi-permeable membrane, and (c) contains factors that regulate lubricant secretion. Lubricant concentration was predicted with different chemical regulators of chondrocy...

OBJECTIVES: Systematic review of outcomes of three treatments for osteoarthritis (OA) of the knee: intra-articular viscosupplementation; oral glucosamine, chondroitin or the combination; and arthroscopic lavage or debridement.DATA SOURCES: We abstracted data from: 42 randomized, controlled trials (RCTs) of viscosupplementation, all but one synthesized among six meta-analyses; 21 RCTs of glucosamine/chondroitin, 16 synthesized among 6 meta-analyses; and 23 articles on arthroscopy. The search included foreign-language studies and relevant conference proceedings.REVIEW METHODS: The review methods were defined prospectively in a written protocol. We sought systematic reviews, meta-analyses, and RCTs published in full or in abstract. Where randomized trials were few, we sought other study designs. We independently assessed the quality of all primary studies.RESULTS: Viscosupplementation trials generally report positive effects on pain and function scores compared to placebo, but the evidence on clinical benefit is uncertain, due to variable trial quality, potential publication bias, and unclear clinical significance of the changes reported. The Glucosamine/Chondroitin Arthritis Intervention Trial (GAIT), a large (n=1,583), high-quality, National Institutes of Health-funded, multicenter RCT showed no significant difference compared to placebo. Glucosamine sulfate has been reported to be more effective than glucosamine hydrochloride, which was used in GAIT, but the evidence is not sufficient to draw conclusions. Clinical studies of glucosamine effect on glucose metabolism are short term, or if longer (e.g., 3 years), excluded patients with metabolic disorders. The best available evidence for arthroscopy, a single sham-controlled RCT (n=180), showed that arthroscopic lavage with or without debridement was equivalent to placebo. The main limitations of this trial are the use of a single surgeon and enrollment of patients at a single Veterans Affairs Medical Center. No studies reported separately on patients with secondary OA of the knee. The only comparative study was an underpowered, poor-quality trial comparing viscosupplementation to arthroscopy with debridement.CONCLUSIONS: Osteoarthritis of the knee is a common condition. The three interventions reviewed in this report are widely used in the treatment of OA of the knee, yet the best available evidence does not clearly demonstrate clinical benefit. Uncertainty regarding clinical benefit can be resolved only by rigorous, multicenter RCTs. In addition, given the public health impact of OA of the knee, research on new approaches to prevention and treatment should be given high priority.

Osteoarthritis is a disabling disease of the aging generation, which results in loss of quality of life and increased healthcare costs. Cytokines appear to play an important role in the cartilaginous degeneration characterizing the pathological process. Increasing experience is being gained with cytokine-modulating therapies aimed at interfering with effects of chondrodegradative cytokines in the synovial fluid. Although in vitro and in vivo effectiveness of several of these therapies has been demonstrated, clinical effectiveness remains disputable, which may be related to the low levels of inflammatory cytokines found in osteoarthritic joints. By contrast, directly after joint trauma, which has been shown to predispose to early osteoarthritis, synovial fluid cytokine levels are strongly increased. Cytokine-modulating therapies, however, have hardly been considered for this indication. Increased knowledge of intra-articular soluble mediators correlating with cartilage pathology will lead to further development of cytokine-modulating products and, eventually, to effective inhibition of cartilage degeneration, in both the osteoarthritic as well as injured joints.