van den Kieboom J, Tirumala V, Xiong L, et al. - The diagnostic performance of serum and synovial fluid markers for diagnosing periprosthetic joint infection (PJI) was examined in patients with a periprosthetic fracture of a total joint arthroplasty. Researchers assessed a total of 144 consecutive patients; 41 patients with concomitant PJI and periprosthetic fracture, and 103 patients with periprosthetic fracture alone. Analysis revealed lower lower diagnostic utility of the serum and synovial markers for diagnosing PJI in the setting of concomitant periprosthetic fracture vs PJI alone. Erythrocyte Sedimentation Rate, C-reactive Protein, and White Blood Cell count demonstrated high sensitivity, yet low specificity, when the MSIS thresholds were used, thus they emphasize considering higher thresholds and utilizing all serum and synovial markers in combination.