Abstract
Background:
Periprosthetic joint infection (PJI) is one of the most devastating complications in patients undergoing total knee arthroplasty (TKA). Although controversy exists about the necessity of the prophylactic use of antibiotics in clean operations, the routine use of antibiotic-loaded bone cement (ALBC) has been the clinical procedure against PJI for many decades. Additionally, the combination of antibiotics has been used to broaden the antimicrobial spectrum and to enhance antimicrobial activity in a revision setting with a potentially resistant organism. Even in primary TKA, the prophylactic combination of antibiotics used as therapy should be considered on patients with a higher susceptibility to bacterial infection based on their clinical histories of PJI, rather than the lower risk population. The purpose of this study is to investigate whether the synergistic combination of antibiotics in bone cement in high risk patients can reduce PJI.
Methods:
A total of 3015 knees of 1918 patients were screened for inclusion in this study based on their risk factor, and those categorized as systematically or locally high risk patients were included. Patients that were classified as “systemically high risk” received an American Society of Anesthesiologists (ASA) classification of 3 or higher and a Charlson Comorbidity Index (CCI) classification of 2 or higher (n = 212 knees, 70.7% of 300 total). Patients that were classified as “locally high risk” had a history of inflammatory arthritis, poor skin conditions, and/or recent septic knee arthritis (n = 76 knees, 25.3%). Patients with both systemically and locally high risk included 12 knees (4.0%). The 300 knees included in this study were separated into three groups based on the combination of antibiotics administered. In group 1(208 knees), gentamycin–impregnated cement was used and in group 2(48 knees) hand-mixed vancomycin with pre-mixed gentamycin cement for intraoperative management was used. In group 3 revision bone cement containing a combination of two antibiotics (gentamycin and clindamycin) was used (44 knees). The mean age was 70.9 years. The number of men and women were 31(10.3%) and 269(89.7%), respectively. The average body mass index (BMI) was 26.7 kg/m2. The incidence of PJI was investigated.
Results:
The systemically high risk, locally high risk, and both cases in group 1 numbered 173 knees (83.2%), 31 knees (14.9%), and 4 knees (1.9%), respectively. In group 2 they numbered 26 knees (54.2%), 18 knees (37.5%), and 4 knees (8.3%), respectively. In group 3, they numbered 13 knees (29.5%), 27 knees (61.4%), and 4 knees (9.1%), respectively. There were no cases of infection in groups 2 or 3 but an infection occurred in one knee (0.3%) in group 1. There were no differences in age, gender, or BMI among groups (p > 0.05).
Conclusion:
We conclude that the use of any ALBC did not seem to affect the incidence of infection following primary TKA. While combination antibiotics have been used by surgeons who may be concerned about PJI after TKA in high risk patients, our results did not indicate a significant difference, and as a result using antibiotics in bone cement to reduce PJI may be just myth.
