Study Of Clinical Characteristics Of Infectious Arthritis Of Knee Following Intra-Articular Injections

Objective:(1) To analyze the effects oftimes, drugs and the levels of hospitals in previous intra-articular injections on the infectious arthritis following injections; (2) To discuss the clinical manifestations of infectious arthritis; (3) To study the diagnostic criteria of infectious arthritis; (3) To discuss the prevention and treatment of infectious arthritis following injections.Materials and Methods:Based on the diagnostic criteria,25 patients during October 2013 to June 2015 were enrolled in the infection group. A control series of 125 randomly selected patients operated during the same period of time, with a history of intra-articular injections within 1 year prior to the hospitalization. The differences in injections, clinical manifestation, and laboratory examinations between groups were compared. The culture results and treatments of the infection group were analyzed.Results:1.Intra-articular injection times of infection group and control group were respectively (4.6 ± 2.2) and (4.3 ± 2.4). No statistically significant difference showed in injection times between groups (P=0.756). The proportion of infection group and control group with intra-articular steroid injection were respectively 60% and 36% (P=0.023); The proportion of infection group and control group with injections in non-class 3-A hospitals were respectively 92% and 69.6%(P=0.014).2.The patients in infection group are more vulnerable to fever, swollen leg, lowered VAS, night pain and worsened HSS (P< 0.05)3.Significant differences were found in serum CRP, serum ESR and mean synovial WBC count between two groups. No statistically significant difference showed in other examinations.4.10 patients have found definite pathogenic bacterium among which Staphylococcus was at the leading role (40%). In our study the culture positive rate was 40%.5. In the infection group,4 patients underwent arthroscopic treatment and other 21 patients underwent two-stage operation, which included implanting bone cement spacer and total knee arthroplasty. The follow-up period was 8 months at least. Only 2 patients who suffered from the infection of the fungus had recurrences of the infection.Conclusion:Intra-articular steroid injections and iatrogenic infection are associated with a significant increase in septic arthritis following injections. The diagnosis of Infectious arthritis depends on bacterial culture, clinical manifestation and laboratory examination. The analysis of synovial fluid has an important value to diagnosis. The treatment of iatrogenic infection includes antibiotic and operative treatment.