“…We enrolled patients who had ESR or CRP testing within 24 h of ED presentation, but did not control for when during the 24-h period testing was done. Our 24-h timeframe corresponds to the time previous studies have shown to be associated with elevated ESR and CRP measurements, but it is possible that our results could vary depending on exactly when testing was performed (9). We used a definition of septic arthritis that we feel captures all patients with a clinically significant joint infection, including those patients who are treated operatively despite indeterminate testing.…”