Abstract
Lateral osteochondral lesions of the talus (OLT) are a notable cause of chronic ankle pain, particularly in cases without a history of trauma. However, their anatomical risk factors remain understudied compared to medial OLTs. This study aimed to identify anatomical factors associated with the development of nontraumatic lateral OLT using magnetic resonance imaging (MRI)-based morphometric measurements. MRI scans from 62 ankles were examined in this retrospective study, comprising 31 patients with lateral OLT and 31 healthy controls matched by age, sex, and side. The following parameters were measured on the MR images: the anterior opening angle of the talus (AOT), the angle between the tibial axis and medial malleolus (TMM), the angle of the tibial plafond to the malleolus, the angle between the anterior and posterior tibiofibular ligaments (ATFL-PTFL angle), the length of the distal tibial articular surface (TAS), the length of the trochlea tali arc (TAL), the ratio of TAS to TAL (TAS/TAL), and the depth of the incisura fibularis (IncDep). AOT, IncDep, ATFL-PTFL angle, TMM, TAL, and TAS/TAL demonstrated significant differences between the 2 groups (P < .05). The threshold values were as follows: 13.5° (area under the curve [AUC] 0.807) for AOT, 80.5° (AUC 0.767) for ATFL-PTFL angle, 16.5° (AUC 0.920) for TMM, and 0.80 (AUC 0.704) for TAS/TAL. Multivariate logistic regression analysis indicated an odds ratio (OR) = 17.805 for AOT ≥ 13.5°, OR = 19.887 for ATFL-PTFL angle > 80.5°, OR = 27.576 for TMM > 1.5° and OR = 4.680 for TAS/TAL ≤ 0.80. These findings suggest that specific anatomical parameters identifiable on MRI, particularly increased AOT, TMM, and ATFL-PTFL angle, are significantly associated with the development of nontraumatic lateral OLT. These parameters may serve as useful imaging biomarkers for clinical risk assessment.