Background: Prosthetic joint infections are a cause of increasing morbidity and medical expenditure.
Objectives: To determine the incidence and the clinical and the epidemiological characteristics of knee and hip prosthetic infections (PI) in patients undergoing elective surgery in five Catalonian hospitals. To determine the predictive factors of PI.
Methods: A total of 425 patients operated on between 8 January and 8 July 2001 were prospectively followed for a period of two years. The cumulative incidence, incidence rate and effect measures were determined. Logistic regression was used to identify variables associated with PI.
Results: Average age was 71 years and 63.1% were women. Antibiotic prophylaxis with cefazolin was given to 44.7% of the patients, with a mean duration of two days. Prophylaxis was administered during anesthesia induction in 75.6% of the patients. Among the total, 63.4% of the patients were ASA 2. Microbiological confirmation was obtained in all the infected patients; Staphylococcus epidermidis was found in 58%. Fourteen PI were diagnosed, 71% during the first 3 months, with a cumulative incidence of 3.29% and a 3-month incidence rate of 63 patients/10,000 patients/month. Diabetes mellitus was the only variable related to PI in the multivariate analysis: 3.18, 95% CI (1.1-9.9).
Conclusions: The cumulative incidence of PI was slightly higher than that seen in other studies. Variations were observed in the antibiotic used for prophylaxis, and the place where it was administered. PI occurred 3.18 times more frequently in diabetic patients.