25 patients with septic knee arthritis were randomized to irrigation through arthroscopy or arthrotomy. The purpose of this study was to compare the effectiveness of each method in treating initial infection, as well as outcomes during a physical examination at 7, 14, 21, and 42 days after surgery. Despite two cases of recurrence observed in the arthrotomy group within the first week, which were managed successfully with repeat irrigation, all patients in both groups demonstrated resolution at 24 months. Significantly lower rates of local warmth and redness over the first 7 days were observed in the arthroscopy group compared to arthrotomy. The arthroscopy group also experience lower pain for the first 14 days. No significant differences in any outcome measure were observed beyond 14 days.