OBJECTIVE: This study aimed to determine the anatomical risk factors that may play a role in the etiology of medial-sided osteochondral lesions of the talus (OLT) using morphological parameters in magnetic resonance imaging (MRI).
METHODS: One hundred twenty-four patients with medial-sided OLT and age- and sex-matched 124 controls were included in this retrospective study. Two examiners conducted independent OLT classification and measurements of five MRI parameters: tibial axis-medial malleolus angle (TMM), the anterior opening angle of the talus (AOT), talus position (TalPos), the ratio of the distal tibial articular surface to the length of the trochlea tali arc (TAS/TAL), depth of the incisura fibularis (IncDep). Statistical analysis included intraclass correlation coefficients, independent t-tests, receiver-operating characteristic (ROC) analysis, area under the curve (AUC) calculation, and logistic regression analysis. A p-value < 0.05 was considered statistically significant.
RESULTS: TTM, AOT, TalPos, and TAL values were significantly higher and the TAS/TAL ratio was significantly lower in the case group than in the control group (p < 0.001). Cut-off and AUC values for TMM were 15.15° (AUC 0.763), AOT 13.05° (AUC 0.826), TalPos 0.75 mm (AUC 0.887), TAL 35.45 mm (AUC 0.642), and TAS/TAL ratio 0.82 (AUC 0.784), p < 0.001. Multivariate logistic regression analysis results were odds ratio (OR) = 6.1 for TMM ≥ 15.15°, OR = 8.9 for AOT ≥ 13.05°, OR = 36.1 for TalPos ≥ 0.75 mm, and OR = 6.7 for TAS/TAL ratio ≤ 0.82.
CONCLUSIONS: Ankle morphology might have an influence on OLT development. The talus position (TalPos) and anterior opening angle of the talus (AOT) seemed to be the strongest predisposing factors.

BACKGROUND: Osteochondral lesions of the talus (OLTs) are common injuries in young, active patients. Microfracture is an effective treatment for lesions less than 150 mm2 in size. Most commonly employed postoperative protocols involve delaying weightbearing for 6 to 8 weeks (DWB), though one study suggests that early weightbearing (EWB) may not be detrimental to patient outcomes. The goal of this research is to compare outcomes following EWB and DWB protocols after microfracture for OLTs.
METHODS: We performed a prospective, randomized, multicenter clinical trial of subjects with unilateral, primary, unifocal OLTs treated with microfracture. Thirty-eight subjects were randomized into EWB (18 subjects) and DWB (20 subjects) at their first postsurgical visit. The EWB group began unrestricted WB at that time, whereas the DWB group were instructed to remain strictly nonweightbearing for an additional 4 weeks. Primary outcome measures were the American Academy of Orthopaedic Surgery (AAOS) Foot and Ankle score and numeric rating scale (NRS) pain score.
RESULTS: The EWB group demonstrated significant improvement in AAOS Foot and Ankle Questionnaire scores at the 6-week follow-up appointment as compared to the DWB group (83.1 ± 13.5 vs 68.7 ± 15.8, P = .017). Following this point, there were no significant differences in AAOS scores between groups. At no point were NRS pain scores significantly different between the groups.
CONCLUSIONS: EWB after microfracture for OLTs was associated with improved AAOS scores in the short term. Thereafter and through 2 years\' follow-up, no statistically significant differences were seen between EWB and DWB groups.
METHODS: Level II, prospective randomized trial.