Background: Several studies have shown that uncomplicated hip or knee arthroplasties induce an abrupt rise in serum C-reactive protein (CRP) concentration for a few days, falling thereafter to preoperative level within a couple of weeks, if no infection is present.

Aim: To evaluate the computer-aided CRP levels analysis in a primary hospital care setting.

Material and Methods: 300 patients undergoing total knee and hip replacements were screened before and for 5 days after arthroplasty. The data were recorded in a database and mathematical algorithm to obtain integral and progressive field surface of the CRP curve.

Results: An elevated C-reactive protein level on the fifth postoperative day correlated positively with the development of acute periprosthetic infection in the first three months postoperatively.

Conclusions: The patient’s individual pattern not following one of the four normal patterns can be argued to necessitate introduction of any infection treatment (whether debridement with retention or antimicrobial therapy alone) within the first three months after the operation.