Evaluation of IVIM-MRI biomarkers for microvascular dysfunction and prognosis in juvenile osteochondritis dissecans of the knee: a single-center study

Microvascular dysfunction of the subchondral bone is thought to play a central role in juvenile osteochondritis dissecans (JOCD), but remains difficult to assess with conventional MRI. This study evaluated the diagnostic value of intravoxel incoherent motion MRI (IVIM-MRI) parameters in JOCD of the distal femoral condyle and explored their relationship with lesion morphology and stability. In this single-center retrospective cross-sectional study, 57 skeletally immature patients (mean age 13.0 ± 2.0 years) with clinically and radiologically confirmed JOCD underwent bilateral knee IVIM-MRI. Quantitative parameters—apparent diffusion coefficient (ADC), perfusion fraction (f), and pseudodiffusion coefficient (D*)—were calculated for lesional and contralateral condyles. Lesion stability was classified on conventional MRI using the Hefti system. Morphological measurements and clinical scores (IKDC, KOOS-Child, Tegner) were recorded. Within-subject comparisons used Shapiro–Wilk testing, paired t-tests or Wilcoxon signed-rank tests, and effect sizes (Cohen’s d). Diagnostic performance for discriminating stable versus unstable lesions was assessed with ROC analysis and multiparametric IVIM models. JOCD lesions showed significantly reduced perfusion fraction (0.178 ± 0.048 vs. 0.253 ± 0.043, p 12 years) revealed no significant differences in microvascular metrics. Based on IVIM profiles, lesions were categorized into three microvascular patterns: preserved (Type I), compromised (Type II), and intermediate (Type III). IVIM-MRI provides quantitative, non-invasive biomarkers that sensitively characterize microvascular compromise in JOCD and support objective assessment of lesion stability. The prognostic utility of these biomarkers for clinical outcomes, however, remains uncertain and warrants validation in prospective studies with arthroscopic ground truth (ROCK classification) and longitudinal follow-up.