Evaluation of patellar height indices in individuals with Osgood–Schlatter disease: a magnetic resonance imaging based study

Aims: To compare magnetic resonance imaging (MRI), derived patellar height indices, the Insall-Salvati Index (ISI), BlackburnePeel Ratio (BPR), and Caton-Deschamps Index (CDI) between adults with Osgood Schlatter disease (OSD) and matched controls, and to determine whether plateau-based indices (BPR, CDI) provide more anatomically reliable assessment of patellar height on MRI than the tuberosity-based ISI in the presence of tibial tuberosity distortion.Methods: In this retrospective study, 350 adults were evaluated, including 175 patients with radiologically confirmed OSD and 175 age- and sex-matched controls. Knee MRI examinations were reviewed using standardized sagittal T1-weighted sequences. Patellar height was assessed using ISI, BPR, and CDI measured independently by two blinded radiologists.Results: Median ISI, BPR, and CDI values were significantly higher in the OSD group (ISI: 1.13 vs. 1.00; BPR: 1.17 vs. 1.00; CDI: 1.23 vs. 1.00; all p0.05). Conclusion: Adults with OSD exhibit significantly increased patellar height across all MRI-derived indices. In the presence of tibial tuberosity distortion, plateau-based indices (BPR and CDI), which reference stable anatomical landmarks and are validated in normal populations, represent a more anatomically robust option for MRI-based patellar height assessment than the ISI.