SAN DIEGO — Patients who developed culture-negative infections following total joint arthroplasty required more operations to clear the infection, according to results presented here.
“The majority of these reoperations were spacer revisions or exchanges and this may not be considered a failure, but more part of the treatment algorithm,” Jason Blevins, MD, said at the American Academy of Orthopaedic Surgeons Annual Meeting.
Blevins and his colleagues collected serum erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) level, preoperative aspiration data and intraoperative cultures for 411 patients who underwent a septic revision for periprosthetic joint infection (PJI) after total joint arthroplasty (TJA). Researchers matched 109 of the patients who had culture-negative PJIs by BMI and age to 109 patients who had culture-positive PJIs. At a minimum of 1 year after surgery, researchers analyzed the number of all-cause revisions and Knee Society Score.
Results showed a significantly higher percentage of repeat interventions among patients in the culture-negative group, with a 24% rate of repeat surgery vs. a 9% rate in the culture-positive group.
“We found a trend toward lower Knee Society Scores in the culture-negative group,” Blevins said. “However, this did not reach statistical significance and may be related to the number of repeat interventions.”
Blevins noted the culture-negative group and the culture-positive group had a significantly different synovial fluid white blood cell count. Compared with the culture-positive group, the culture-negative group had a lower percent of polymorphonuclear leukocytes. However, results showed no difference in the CRP and ESR measures between the groups. – by Casey Tingle
Blevins J, et al. Paper #468. Presented at: American Academy of Orthopaedic Surgeons Annual Meeting. March 14-18, 2017; San Diego.
Disclosure: Blevins reports no relevant financial disclosures.