Microorganisms in Presumed Aseptic Revision Hip and Knee Arthroplasty
Abstract
The role and clinical significance of microorganisms in presumed aseptic revision total hip (THA) and knee arthroplasty (TKA) is unclear. The primary aim of this thesis was to determine the prevalence and infection-free survival of presumed aseptic revisions with unexpected positive intraoperative cultures (UPC) by analyzing the largest cohorts of UPC in the literature. Secondarily, a prospective pilot study using modern molecular techniques with an emphasis on stringent control of contamination was designed to determine how frequently microorganisms are present on implants of presumed aseptic revisions, as well as their location and association with reason for revision.
The prevalence of UPC was approximately 10%, the infection-free survival is encouraging, and the infection-free survival from the same UPC microorganism is outstanding. Patients with ≥2 UPC or a single UPC treated with antibiotics were more likely to have recurrent infection caused by the UPC microorganism. Patients with a single UPC and no other signs of infection do not require antibiotic treatment
The rate of UPC in the prospective molecular pilot study was also approximately 10% and we hypothesize that microorganisms will frequently be found on implants of ‘aseptic’ failures and associated with location and reason for revision.