Comparative analysis of femoro-tibial synostosis results in periprosthetic infection

Introduction Periprosthetic infection (PJI) after total knee arthroplasty remains a serious challenge for orthopedic surgeons and requires radical treatment methods. Femoro-tibial synostosis (FTS) is one of the last salvage operations if revision arthroplasty fails or impossible. However, there is currently no consensus on a rational technology that would provide an optimal anatomical and functional result of surgical rehabilitation. The aim of the work was to analyze clinical outcomes of surgical treatment performing FTS of the knee joint in the patients with PPI using an intramedullary nail (IN) versus the Ilizarov apparatus (IA). Materials and methods A comparative analysis of 46 patients with PPI who underwent arthrodesis of the knee joint (AKJ) was performed. The patients were divided into two groups depending on the osteosynthesis technology for bone fusion between the femur and tibia: 25 patients in group 1 (IN) and 21 in group 2 (IA). The clinical characteristics of the patients, comorbid background, type of bone defects and microbiological profile were assessed. Statistical analysis of the comparison of functional results, timing of ankylosis, limb shortening, recurrent infections and complications was performed using the Jamovi software (version 2.6.17). Results The average time of bone fusion was significantly shorter in group 1 (IN), 4.5 months versus seven months in group 2 (IA), p = 0.027. Functional results of the groups were comparable (p = 0.075). In defects with significant bone loss (AORI type III), patients in group 2 (AI) demonstrated better LEFS indicators (p = 0.018). The infection recurrence rate was 13 % in group 1 (IN) and 4.8 % in group 2 (IA), p = 0.609. Systemic complications (6.5 %) were detected only in group 1 (IN). Adverse events were considered using the unified classification of complications. Discussion The obtained results indicate that IN and IA provide comparable treatment efficacy in patients with PPI with differences in the timing of bone fusion and functional indicators in significant bone defects. The increasing prevalence of multiresistant microflora and the frequency of complications require a careful and individual approach to the choice of the FTS technique. Conclusion The results of the study demonstrate the effectiveness of both techniques: the use of IN contributes to a more rapid bone fusion between the femur and tibia, while IA provides better anatomical and functional results in patients with significant bone loss.