Altered femoral articular cartilage morphology and composition in physically active males with recurrent lateral ankle sprains: A case-control MRI study

Alterations in knee joint biomechanics have been observed in individuals with recurrent lateral ankle sprain, potentially affecting knee joint health. However, it remains unclear whether femoral cartilage morphology and composition are associated with recurrent lateral ankle sprain. We aimed to compare femoral cartilage cross-sectional area and T2 relaxation times using magnetic resonance imaging between individuals with and without recurrent lateral ankle sprains. In this single-blinded, case-control study conducted at a university imaging laboratory, 15 male participants with recurrent lateral ankle sprains (age = 21.3 ± 1.8 years, height = 177.2 ± 5.1 cm, body mass = 68.7 ± 5.8 kg) and 15 healthy controls (age = 21.3 ± 1.9 years, height = 173.7 ± 6.6 cm, body mass = 64.6 ± 5.7 kg) were included. Bilateral femoral articular cartilage images were acquired using T2 mapping compositional magnetic resonance scans of the tibiofemoral joint. A single reader manually segmented the medial cartilage on a sagittal image slice to evaluate the cross-sectional area and T2 relaxation time. A two-way repeated measures analysis of variance with Bonferroni post hoc analyses was used to analyze the magnetic resonance variables. Hedge g effect sizes using the pooled standard deviations were calculated, along with 95% confidence intervals (CIs) for each pairwise comparison. There were no differences in anthropometric characteristics between individuals with and without recurrent lateral ankle sprain ( P  > .05). Participants with recurrent lateral ankle sprains exhibited a significantly greater femoral cartilage cross-sectional area than healthy controls, regardless of limb dominance ( P  = .03, η ²  = 0.16). In addition, T2 relaxation times were significantly longer in the dominant limb of participants with recurrent lateral ankle sprains than in healthy controls ( P  = .02, Hedge g  = 0.88, 95% CIs: 0.14–1.61) and in their nondominant limb ( P  = .03, Hedge g  = 0.72, 95% CIs: 0.16–1.25). No significant differences were observed between the dominant and nondominant limbs in the control groups ( P  = .23, Hedge g  = ‐0.26, 95% CIs: −0.74 to 0.24) or between the recurrent lateral ankle sprain and control groups in the nondominant limb ( P  = .74, Hedge g  = −0.12, 95% CIs: −0.82 to 0.61). These findings indicate altered femoral articular cartilage morphology and composition in participants with recurrent lateral ankle sprains. The findings of this study support the need for monitoring knee joint function and symptoms during rehabilitation in patients with recurrent lateral ankle sprains. A prospective longitudinal study with a larger and more diverse sample is needed to investigate these associations further.