Purpose of the study: Factors affecting the course of Staphylococcus aureus (SA) infected total hip arthroplasty (THA) and total knee arthroplasty (TKA) are poorly understood.

Material and methods: The microbiology laboratory database on patients hospitalised from June 2001 to June 2006 for medical and surgical treatment of an SA infected THA or TKA were reviewed. Data collected were: clinical, radiological, and biological (CRP) status known at least two years after the end of the antibiotic treatment. Success was defined as normal findings in all three domains at last follow-up and failure for any other situation.

Results: The series included 87 patients (43 male and 54 female, mean age 66.5 years, 62 THA, 35 TKA). Material was removed in 51 patients (52.6%). The infection was related to met-R SA in 14 patients (14.4%) and polymicrobial infection in 24 patients (24.7%). Mean duration of intravenous treatment was 7.3±9.4 days and total duration of antibiotic treatment was 115.472.2 d. At mean follow-up of 54.1±19.4 d, the overall success was 62/97 (63.9%). The only parameters significantly associated with failure were delay to management after first signs revealing longer infection (67.9 days vs 144.8 days) and an antibiotic therapy not adapted bacteriological results to immediately after surgery. (28.6% vs 3/28; 4.8%). In this series, met-R SA was not a risk factor of failure.

Conclusion: This work suggests that delayed surgical management and quality of antibiotic treatment for the first revision are factors affecting the prognosis of SA infected THA and TKA. These results are in favour of a multidisciplinary approach to care for these patients.