Prevalence and Impact of Unexpected Positive Intraoperative Cultures in Total Hip or Knee Revision Surgery

Our aim was to evaluate the prevalence and impact of unexpected positive intraoperative cultures (UPICs) on the outcome of presumed aseptic total knee and hip revision surgery.

Data regarding patients who underwent elective total hip or knee revision surgery from January 2003 to July 2017 due to preoperatively presumed aseptic reasons was retrospectively reviewed. Partial revisions and patients who had follow-ups below 60 months were excluded from the study. In all surgeries, at least 3 intraoperative samples were taken for microbial culture. Failure was defined as the need for rerevision due to any cause at 5 years and/or the need for antibiotic suppressive therapy. Overall, 123 total hip and 431 total knee revisions were eligible for the study. All cases had at least a 5 years follow-up.

There were 420 cases (75.8%) that had all cultures negative, 108 (19.5%) had a single UPIC, and 26 (4.7%) had either ≥2 UPICs for the same microorganism or 1 UPIC for a virulent microorganism. This latter group was not associated with a significantly higher failure rate (2 of 26, 7.7%) compared to those in the aseptic group (54 of 528, 10.2%). Revisions performed within the first 24 months after primary implantation had a higher 5-years rerevision rate (19.3 versus 8.4%, P = .01), mainly attributable to aseptic causes.

Total hip and knee revisions with UPICs were not significantly associated with a higher rerevision risk at 5 years. Those revisions performed within the first 24 months after primary arthroplasty had a higher rate of any-cause failure.