Use of a provincial surveillance system to characterize postoperative surgical site infections after primary hip and knee arthroplasty in Alberta, Canada.

•Surveillance is used to discover pathogens of surgical site infection posthip and -knee arthroplasty.•Infections after knee arthroplasty tend to occur later versus hip arthroplasty.•Preoperative colonization with methicillin-resistant Staphylococcus aureus (MRSA) is more likely to cause an MRSA surgical site infection.