RESUMO
The present study was done to detect the incidence of Hydroxy apatite [HA] Calcium. Pyrophosphate Dihydrate [CPPD] and monosodium urate [MSU] crystals in synovial fluid of inflammatory Osteoarthritis [OA] by using alizarin red S stain and polarized light microscopy This study included 100 patients, 83 females [83%] and 17 males [17%] and their ages were ranged between 38-65 years with a mean of 45.9-1.3 years. HA was detected in 36% of cases, CPPD was detected in 30% of cases MSU was detected in 5% of cases while 55% of cases had no crystals in their synovial fluid. Also we found that there was coexistence between HA and CPPD crystals in 16 cases of those who had crystals in their synovial fluid [45 patients] and also the difference in the incidence between AH and CPPD crystals was statistically in-significant, while the difference between the incidence of HA and MSU as well as the difference between the incidence CPPD and MSU crystals was statistically significant. We concluded that alizarin red S staining is a rapid simple and sensitive technique helpful in detecting the presence of aptite crystals and that the concordance of HA and CPPD crystals might be of potential clinical and pathogenic significance