Advances in management of periprosthetic joint infections: an historical prospective study

The purpose of our study is to assess the incidence of prosthetic joint infection (PJI) after total Knee arthroplasty (TKA), total Hip arthroplasty (THA) and total Shoulder arthroplasty (TSA), to identify risk factors, determine the microbial spectrum and management's outcome.

A case-control, retrospective observational study was performed analyzing patients who developed a PJI after TKA, THA, and TSA from 2000 to 2017 at our hospital. The patient's risk profile was defined extracting from clinical records the following data: sex, age, BMI, type of implant, comorbidity, year of surgery, year of infection, previous intra-articular injection, microbial isolation, medical and surgical management outcome. We include in the "control group" for each "case" at least 3 patients who didn't have a PJI after TJA.

28 patients met all inclusion and exclusion criteria. Comparing the "cases" with "controls" demographics parameters, medical comorbidities and previous intra-articular injection were not associated with an increased risk of PJI. Comparing the "early/delayed group" with "late group", BMI was associated with an increased risk of early/delayed PJI, while demographics parameters, medical comorbidities, and previous intra-articular injection did not significantly increase the risk of PJI. Logistic regression showed that for each BMI unit there was a 20-fold increased risk of early prosthetic infection (OR 1.19, IC 1.03-1.38, p=0.01). Staphylococci were isolated most frequently from pre-operative and intra-operative cultures. Two-stage arthroplasty exchange and surgical debridement resulted in the most performed surgical treatment with a success rate of 88 and 87%.

Obesity is a risk factor for "early/delayed infection" of TJA. Two-stage arthroplasty exchange, debridement, antibiotics, and implant retention in patients are treatments with a high rate of success in terms of reinfection.