[C-reactive protein as a postoperative parameter of infection in hip joint replacement and knee joint operations]

Prospectively 70 male patients with elective arthroplasty of the hip (n = 34) and with operation of the anterior cruciate ligament (n = 36) were studied in respect of the postoperative screening of C-reactive protein (CRP), the erythrocyte sedimentation rate (ESR), the white blood cell count and the clinical signs of infection. There were 9 infectious postoperative complications, all with an increase of CRP. But also 6 other patients with no clear infection showed a rise or a plateau of CRP, which could only be explained by the presence of a hematoma, an effusion or a subclinical infection. The close postoperative screening of CRP appeared to be quite costly and laborious, especially in a population with a low infection rate. We therefore suggest a CRP-screening only on patients or operative procedures with wellknown high risk. In addition we studied the determination of two CRP-levels with a short interval following the clinical suspect of a postoperative infection (described in part II of this paper).