Trochlear Dysplasia and Its Structural Correlates on Knee Magnetic Resonance Imaging: A Multiparametric Analysis

Year 2026, Volume: 12 Issue: 1, 59 - 67, 04.01.2026

Gizem Timoçin Yığman , Hande Özen Atalay

https://doi.org/10.18621/eurj.1748832

Abstract

Objectives: 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<0.0001 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.

Keywords

Trochlear Dysplasia , Chondromalacia , Meniscal Degeneration , Patella Alta , ACL Mucoid Degeneration , Patellofemoral Instability

Ethical Statement

This study was approved by the Koç University Biomedical Research Ethics Committee (Decision No: 2025.223.IRB2.103; date: 13.05.2025). All procedures were conducted in accordance with the ethical standards of the institutional and national research committee and with the 1964 Helsinki Declaration and its later amendments. The study had retrospective design, no additional procedures were performed. Informed consent forms are obtained from each patient before the radiological examination in our institution as a clinical routine.

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