Infected Total Knee Replacement

Though total knee replacement is a very successful procedure there is a small risk of infection of about 0.5 to 1%. Infection can be classified depending on the chronology of occurrence as

• Acute - within 6 weeks
• Subacute- 6 weeks to 3 months
• Chronic- more than 3 months.

Acute infection is confirmed by clinical findings, aspiration and culture of the joint fluid. Acute infection can be treated with intravenous antibiotics and joint lavage with the exchange of insert and retention of the prosthesis. One or two attempts at the retention of the prosthesis may be successful. Intermittent short course suppressive antibiotic therapy is also helpful in preventing a recurrence. Subacute or chronic infection or failure to salvage in acute infection can be treated by two staged revision of the prosthesis. Initial debridement after discontinuation of all antibiotics for a few weeks with multiple intraoperative cultures, fixation of the antibiotic-laden articulating spacer, a short course of appropriate antibiotic intravenously followed by oral antibiotics for 8 to 12 weeks followed by second stage revision at present one of the successful protocols.