Difficult-to-Detect Low-Grade Infections Responsible for Poor Outcomes in Total Knee Arthroplasty.

In this article, we present the case of a patient with a stiff, painful knee after total knee arthroplasty, and with erythrocyte sedimentation rate, C-reactive protein level, and synovial fluid analysis within normal limits. Open biopsy for cultures showed Propionibacterium acnes prosthetic joint infection, which was successfully treated with 2-stage revision and intravenous antibiotics.