aseptic failure of a knee prosthesis is not associated ..
prosthetic joint failure, the appearances of aseptic loosening and ..
In cases where the diagnosis of Prosthetic Joint Infection has not been established preoperatively, assessment for acute inflammation on intraoperative frozen section provides rapid intraoperative assessment for Prosthetic Joint Infection, with sensitivities of 43-100% and specificities of 77-100% (using cutoffs varying from >5 to ³10 polymorphonuclear leukocytes per high power field).
Prosthetic Joint Infection Diagnosis [Hot Topic] - Insights
The most useful pre-operative diagnostic test (where there is uncertainty) is joint aspiration for total and differential cell count and culture. Aspiration should not be performed through overlying cellulitis. A synovial fluid leukocyte count of more than 1.7x103/μl or a neutrophil percentage of more than 65% is consistent with prosthetic knee infection. Hip aspiration may require imaging guidance. A synovial fluid leukocyte count of more than 4.2x103/μl or a neutrophil percentage of more than 80% is consistent with prosthetic hip infection. These cutoffs are dramatically lower than those used to diagnose native joint infection. Synovial fluid culture has a sensitivity ranging of 56 to 75% and specificity of 95 to 100%, and to achieve ideal sensitivity and specificity should be performed by inoculation into a blood culture bottle. If an organism of questionable clinical significance is isolated, repeat synovial fluid aspiration for culture should be considered. Prior antimicrobial therapy reduces sensitivity.