Results of periprosthetic hip and knee infections caused by resistant bacteria.

Seventy patients with deep periprosthetic hip or knee infections were treated between May 1997 and March 2001. Thirty-five patients had periprosthetic infections of their total hip arthroplasties and 35 patients had periprosthetic infections of their total knee arthroplasties. The patients were subdivided into two subgroups: patients who had infections with Staphylococcal bacterial strains that were sensitive to methicillin and patients who had infections with bacteria that were resistant to methicillin (methicillin-resistant Staphylococcus aureus and methicillin-resistant Staphylococcus epidermidis). Treatment was considered successful if the patient was able to retain his or her hip or knee prosthesis either as a result of irrigation and debridement procedures alone or after excision of the infected total hip or knee prosthesis followed by successful reimplantation. Treatment was considered a failure if the patient eventually required arthrodesis, amputation, or was left with a permanent excision arthroplasty. Hip replacements that were infected with antibiotic-sensitive bacteria were treated successfully in 81% of cases. In contrast, hip replacements infected with resistant organisms were treated successfully in only 48% of cases. Similarly, knee replacements infected with sensitive organisms had a success rate of 89%, compared with only 18% of the total knee replacements that were infected with resistant bacterial strains.