Abstract
Introduction: Despite exhaustive prophylactic measures, intra-operative contamination still occurs following cemented arthroplasty. We undertook a prospective study to identify the incidence of intra-operative deep wound contamination in cemented joint arthroplasty. Furthermore, we assessed the medium term incidence (at 4 years) of wound contamination in this patient cohort.
Materials & Methods: A total of 82 consecutive patients admitted for elective cemented arthroplasty were enrolled in the study over a 6 month period. Standard medical and dental work up was performed prior to admission to assess fitness for surgery. Pre-operative wound site preparation included Hibitane showers and painting and draping of the operative site in both the anaesthetic room and theatre. All cases were undertaken in an ultra-clean laminar airflow theatre and the surgical team wore isolation suits in all cases. Standard swabs from skin incision and deep in the wound were sent in addition to the blades and suction tip used. Cultures were typed by morphology and identified by standard techniques. A control swab was sent from all cases to exclude contamination occurring in the laboratory setting.
Results: A total of 82 patients were included in the study. Mean patient age was 67.4 years (36–85 years). Of the 82 procedures performed, 59 were total hip replacements and 23 total knee replacements. Five procedures were performed for revision arthroplasty (1 knee and 4 hips). 19 of the 82 cases (23%) examined grew contamination organisms with S. epidermidis being the commonest organism (16). In 16 cases a single specimen demonstrated contamination. 2 patients had 2 contaminated specimens and 1 had 3 contaminated specimens. No significant correlation between the duration of the case, number of personnel in theatre, or the seniority of the operating surgeon was demonstrated. On medium term follow up (mean 49.6 months, 95% CI 3.2 months) no patient had developed clinical evidence of infection.
Conclusion: We noted a high incidence of intra-operative contamination of cemented arthroplasties despite standard prophylaxis. However, this was not reflected by a similar rate of post-operative infection. This may be due to a small bacterial innoculum in each case or possibly may be due to the therapeutic effect of peri-operative intra-venous antibiotic prophylaxis.
The abstracts were prepared by Emer Agnew, Secretary to the IOA. Correspondence should be addressed to him at Irish Orthopaedic Association Secretariat, c/o Cappagh National Orthopaedic Hospital, Finglas, Dublin 11, Ireland.