The new OMERACT definitions for the US identification of CPPD proved to be reliable at the level of the HC and FC of the knee. Further studies are needed to better define the US characteristics of CPPD and optimize the scanning technique in other anatomical sites.

Based on the results of our exercise, the OMERACT US definitions for the identification of CPPD demonstrated to be reliable when applied to the TFC and AC. Other sites reached good kappa values in the web-based exercise but failed to achieve good reproducibility at the patient-based exercise, meaning the scanning method must be further refined.

ObjectiveTo evaluate the discriminatory ability of ultrasound in calcium pyrophosphate deposition disease (CPPD), using microscopic analysis of menisci and knee hyaline cartilage (HC) as reference standard.MethodsConsecutive patients scheduled for knee replacement surgery, due to osteoarthritis (OA), were enrolled. Each patient underwent ultrasound examination of the menisci and HC of the knee, scoring each site for presence/absence of CPPD. Ultrasound signs of inflammation (effusion, synovial proliferation and power Doppler) were assessed semiquantitatively (0–3). The menisci and condyles, retrieved during surgery, were examined microscopically by optical light microscopy and by compensated polarised microscopy. CPPs were scored as present/absent in six different samples from the surface and from the internal part of menisci and cartilage. Ultrasound and microscopic analysis were performed by different operators, blinded to each other’s findings.Results11 researchers from seven countries participated in the study. Of 101 enrolled patients, 68 were included in the analysis. In 38 patients, the surgical specimens were insufficient. The overall diagnostic accuracy of ultrasound for CPPD was of 75%—sensitivity of 91% (range 71%–87% in single sites) and specificity of 59% (range 68%–92%). The best sensitivity and specificity were obtained by assessing in combination by ultrasound the medial meniscus and the medial condyle HC (88% and 76%, respectively). No differences were found between patients with and without CPPD regarding ultrasound signs of inflammation.ConclusionUltrasound demonstrated to be an accurate tool for discriminating CPPD. No differences were found between patents with OA alone and CPPD plus OA regarding inflammation.

Background and Objective Clodronate is a nitrogen-free bisphosphonate that is widely and effectively used in the treatment of many osteo-metabolic disorders. The objective of our study was to evaluate the effectiveness of clodronate in reducing pain and bone marrow edema in knee osteoarthritis. Methods In total, 74 patients were included in the study. Group 1 received intramuscular clodronate 200 mg daily for 15 days and then once weekly for the next 11.5 months; group 2 received intramuscular clodronate 200 mg daily for 15 days and then once weekly for the next 2.5 months. Visual analog scale (VAS) scores were recorded at baseline (T0) and after 30 days (T1), 3 months (T2), 6 months (T3), 9 months (T4), and 12 months (end of study; T5). We also evaluated functional status and use of paracetamol (T0, T1, T2, T3, T4, and T5) and changes in Whole Organ Magnetic Resonance Imaging Score (WORMS; T0, T2, and T5). Results Both groups had a statistically significant reduction in VAS score until 3 months. Group 1 then experienced further VAS reductions, whereas VAS scores for group 2 progressively increased. Pain, stiffness, and physical function also showed the same trend, as did bone marrow edema extension, which was evaluated with WORMS. Conclusion Our study indicates that intramuscular administration of a therapeutic dose of clodronate followed by a maintenance dose is effective in the management of symptomatic knee osteoarthritis, improving functional outcomes and reducing pain and bone marrow edema. Prolonged treatment increases the long-term efficacy of clodronate compared with the shorter schedule.

ObjectiveOsteoarthritis (OA) and calcium pyrophosphate deposition disease (CPPD) are frequently associated but the real relation between these diseases is not still understood. The aim of this paper is to investigate the characteristics in terms of inflammation, anatomical changes and synovial fluid (SF) features in knees of patients with OA and CPPD. MethodsConsecutive patients older than 55 years with knee pain and swelling were enrolled. All patients underwent a complete clinical examination, a US examination of the affected joint, arthrocentesis of the knee and analysis of synovial fluid, including dosing of inorganic ions and number of crystals. The gold standard for the diagnosis was the microscopic analysis of the SF. ResultsSixty-seven patients were enrolled, 25 affected by OA and 42 by CPPD. At US, a significantly higher amount of effusion and synovitis was identified in patients with CPPD but there were no significant differences regarding structural changes. At the SF analysis, the white blood cell (WBC) count was higher in patients with CPPD who also presented a higher number of polymorphonuclear cells and a lower number of monocytes. Regarding the inorganic ion concentration, the statistical analysis did not reveal any differences. The number of crystals in the SF, correlated with a larger effusion, higher grade of synovitis and a higher WBC count. ConclusionA higher degree of inflammation was found in patients with CPPD. The findings suggest that longitudinal studies would be useful to better understand the evolution of the diseases and highlight the need for different treatment strategies.