Long-term results of periprosthetic infection prevention and treatment in oncoorthopedics

BACKGROUND: Endoprosthesis after bone and joint resection is the treatment of choice for patients with malignant bone tumors, especially in case of a favorable oncological prognosis. Endoprosthesis bone site infection and relapse associated with the underlying disease are important complications that are difficult to treat. The development of periprosthetic infection leads to the loss of functional potential after the end of this complication treatment and worsens oncologic prognosis. AIM: To study and improve the long-term results of treatment in patients with diagnosed periprosthetic infection who underwent oncologic endoprosthesis, to develop a preventive complex of measures aimed at reducing periprosthetic infection. MATERIAL AND METHODS: The study included 1292 patients with primary bone sarcomas, soft tissue sarcomas, metastatic and benign bone tumors who underwent 1671 primary and recurrent endoprosthetic replacements between January 1992 and January 2020. A total of 677 (52.4%) men and 615 (47.6%) women participated in the study. Patients ranged in age from 10 years to 81 years. Oncologic endoprosthetics were performed in 886 (68.6%) patients with primary malignancies, 144 (11.1%) with metastatic bone lesions, and 262 (20.3%) with benign neoplasms. The mean follow-up period after endoprosthetic replacement with various bone segments was 82.8 months (0-335.7 months). RESULTS: The incidence of periprosthetic infection during the entire follow-up period in primary endoprosthesis was 7.1%, and in repeat endoprosthesis 6.2%. The recurrence rate of endoprosthesis infection in primary endoprosthesis during the observation period was 83%, in repeat endoprosthesis 61.5%. The frequency of periprosthetic infection was reduced by changes in the endoprosthetic strategy. The prevalence of early (type IVA according to ISOLS 2013) infectious complications (15 and 11.9%) over late (type IVB) complications (5 and 4.4%, respectively) in both primary and repeat arthroplasty was higher. Staphylococcus aureus was most frequently identified after primary endoprosthetic replacement (38.1%) and Staphylococcus epidermidis was most commonly verified after repeat endoprosthetic replacement (53%). Two-stage reendoprosthesis was used most often to treat periprosthetic infection: after primary endoprosthesis in 58.3% of cases, after repeat endoprosthesis in 65.4%. The preventive measures developed in the study made it possible to reduce the incidence of the endoprosthesis site early infection by 15.3% in primary endoprosthesis and by 7.1% in repeat endoprosthesis. CONCLUSION: The perioperative antibiotic prevention regimen should provide a steady antibiotic concentration during the entire course of surgery and the time associated with the highest risk of endoprosthesis site early infection (extended antibiotic treatment up to 5 days), which allows to reduce the wound microbial contamination to a safe level. The findings suggest that two-stage reendoprosthetic replacement remains the main treatment option for periprosthetic infection.