This tool supports structured infectious-disease decision making but does not replace clinician judgement or local guideline pathways.
This OpiCalc infectious-disease entry reflects commonly used guideline criteria and bedside risk features used in contemporary clinical practice.
MSIS Criteria: Major and minor prosthetic joint infection diagnostic features.
Sinus tract to prosthesis
+3 Points
Two positive cultures with same organism
Elevated synovial WBC/PMN
+2 Points
Elevated ESR or CRP
+1 Points
Purulence around prosthesis
Positive histology / single culture
Assessment Tier
Score 0
Selected features provide limited support for PJI.