Analysis for osteoarthritis of the ankle joint in a mouse model of chronic ankle instability.

ObjectiveThis study aimed to assess osteoarthritic changes in the ankle joint in a surgical model of chronic ankle instability (CAI) in mice.MethodsThis experimental study was conducted this study using 14-week-old Institute of Cancer Research (ICR) male mice (n = 19), divided into the sham control ([SH], n = 5), anterior talofibular ligament resection ([ATFL]; mild sprain, n = 7), and ATFL + calcaneofibular ligament resection ([ATFL + CFL]; severe ankle injury, n = 7) groups. A combination of behavioral analysis, micro-computed tomography, immunohistochemical staining, and serological analysis through enzyme-linked immunosorbent assay was performed to evaluate the outcomes.ResultsA decrease in hind-leg standing was observed in the injured mouse groups, indicating signs of discomfort. Significant deterioration in cartilage integrity and joint structure was quantitatively confirmed in the ATFL + CFL group. Increased cartilage erosion and subchondral bone damage were observed. Serological analysis revealed elevated levels of inflammatory cytokines (TNF-α, IL-6, and IL-1β) in the ATFL + CFL group, suggesting a heightened inflammatory response.ConclusionsThis study demonstrated that severe CAI, particularly that involving both the ATFL and CFL, directly contributes to the development of ankle osteoarthritis. This highlights the critical need for targeted interventions in preventing or mitigating this progression.