Introduction: Hot swollen knee joints are a common presentation in clinical practice. It has wide differential diagnoses, the most serious being septic arthritis. Delayed or inadequate treatment leads to joint damage. Arthroscopic lavage should be planned appropriately after proper clinical assessment and investigation. Other differential diagnoses like crystal arthritis, reactive arthritis, monoarticular inflammatory arthritis should be considered.

Patients and Methods: This retrospective audit involved 44 patients who had arthroscopic knee lavage for suspected septic arthritis from January 2005 to May 2007. Analysis included the aspects of adequate backup supportive evidence for the procedure, the time from diagnosis to operation and postoperative antibiotic regime.

Results: There were 29 males and 15 females with age group ranging from 11 to 91 yrs. Fever was present in 15 patients(34%), preoperative joint aspiration done in 22(50%), peri-operatively pus found in 11(25%). 13 patients(29.5%) had procedure done within 6hrs, causal organism identified in 25%. Follow-up ranged upto 12 months without persistence or reactivation.

Discussion: Arthroscopic lavage is a useful adjunct in treatment of septic arthritis of knees but proper patient selection with systematic approach considering other possible differential diagnoses is important for avoiding unnecessary operations.