Aim: To determine the surgical site infection (SSI) rates for prosthetic hip and knee replacement surgery.
Materials and Methods: Between April 2002 and March 2003 the Infection Control team in conjunction with the Orthopaedic Department had participated in national surveillance project to determine the surgical site infection rates for prosthetic hip and knee replacement surgery. Information was collected relating to surgeon specific data and patient risk index. Each surgeon was given a unique confidential code and patients intrinsic risk of infection calculated based on ASA grade, wound class and the duration of surgery.
Results: During the first year of surveillance 455 prosthetic hip replacements were undertaken (i.e. hemiarthroplasty, primary and revision surgery). A total of 12 patients were identified with an SSI giving an average of 2.6% compared with national figure of 3.0%. Out of this 25% (3) superficial and 75%(9) deep-seated infection with Methicillin Sensitive Staphylococcus Aureus (MSSA) and MRSA being the commonest organisms.
234 prosthetic knee replacements (Primary and Revisions) were carried out over the same period of time with 7 cases identified with SSI, an average incidence of 3% compared with national average of 1.6%. Three were superficial and four with deep infection with MRSA, MSSA and coagulase negative staphylococci being the commonest organisms.
MRSA containment policy was introduced in November 2002 with pre operative screening,” ring fencing” orthopaedic patients and improved awareness of cross infection. Since then over the last 4 months of this study the incidence of SSI has fallen from 3.3% to 1.9% in prosthetic hip surgery and 5.8% to 0.7% in prosthetic knee surgery in comparison to previous quarter.
Conclusion: Significant cost and morbidity are associated with infection of the prosthetic joint. With simple measures like improved awareness of cross infection among the staff and relatives, ”ring fencing” orthopaedic patients and pre operative screening surgical site infection rate can be reduced.
