Trochlear dysplasia and its structural correlates on knee magnetic resonance imaging: a multiparametric analysis

Abstract

To investigate associations between trochlear dysplasia severity and various morphometric and degenerative findings on knee Magnetic Resonance Imaging (MRI) Methods: A total of 211 knee MRIs from 181 patients diagnosed with trochlear dysplasia between November 2012 and March 2025 were retrospectively reviewed. Morphometric parameters - sulcus angle, trochlear depth, tibial tuberosity to trochlear groove (TT-TG) distance, patellar angle, and patellar position - were measured. Chondromalacia patella (grades 0-4), meniscal degeneration and tear, and Anterior Cruciate Ligament (ACL) mucoid degeneration were also recorded. Statistical analyses included ANOVA, Kruskal–Wallis, and chi-square tests. Results: Trochlear dysplasia type A was the most common (61.1%). Significant associations were found between trochlear dysplasia severity and sulcus angle, TT-TG distance, and trochlear depth (P&lt0.0001 for all). While chondromalacia presence did not differ significantly across trochlear dysplasia types (P=0.203), its severity correlated with trochlear dysplasia grade (P=0.036). Meniscal degeneration was also significantly associated with trochlear dysplasia (P=0.0004), particularly when both menisci were involved (P=0.003). No significant associations were found for patellar angle, patellar position, meniscal tear, or ACL mucoid degeneration. Conclusions: Trochlear dysplasia is significantly linked to specific morphologic and degenerative MRI findings. A comprehensive MRI-based assessment may aid in the diagnosis and management of patients with anterior knee pain and patellofemoral instability.