Two-stage revision of infected hip arthroplasty using an antibiotic-loaded spacer: retrospective comparison between short-term and prolonged antibiotic therapy.

The optimal duration of systemic antibiotic therapy in patients with prosthetic hip infection (PHI) undergoing staged exchange arthroplasty (SEA) has not been determined. We hypothesized that with an antibiotic-loaded cement spacer (ALCS), in the interim, short-term antibiotic therapy is as effective as a conventional prolonged treatment course. We reviewed 99 patients with PHI who were managed with SEA using an ALCS from February 2002 to October 2005. A standard (4-6 week) antibiotic treatment course was administered in the first 46 patients and a short-term (1 week) therapy was adopted in the subsequent 53 patients. Eight patients (four in each group) had persistent infection following the first attempt of surgery and antibiotic treatment; in three of them the infection was cured by additional debridement prior to re-implantation. Forty-two (91%) patients in the long-term group and 47 (89%) patients in the short-term group were free of infection (P = 0.67) at an average follow-up of 43 months (range, 24-60 months). Five (11%) patients developed complications related to prolonged antibiotic therapy. The short-term treatment resulted in a shorter hospital stay (18 versus 43 days, P < 0.001) and a lower direct medical cost (US$13 732 versus US$21 756, P < 0.001). Short-term antibiotic therapy was not associated with a higher rate of treatment failure. Given the higher costs and incidence of complications, protracted courses of antibiotic administration may not necessarily be routine practice in patients with PHI undergoing SEA, provided that an ALCS is used.