MRI Evaluation of Trochlear Dysplasia as a Cause of Patellar Instability

Abstract

Background: Trochlear dysplasia is characterized by abnormal trochlear morphology and a shallow groove and is known to be a major risk factor for patellofemoral instability. About 96% of patients with a history of a true patellar dislocation had evidence of trochlear dysplasia. Patients and methods:This study included 100 patients, their ages range between 12-60 years. All presented with anterior knee pain and had MRI examination after orthopedic consultation.Results: In this study, trochlear dysplasia is diagnosed in 16 patients among other knee disorders. Trochlear dysplasia type A is found in 6 patients, type B in 6 patients, and type C in 4 patients. Trochlear groove depth by (mm), trochlear facet asymmetry by (%) and lateral inclination angle by degree (°) were calculated for all trochlear dysplasia cases. Conclusion:Different parameters can be used for MRI evaluation of the trochlear dysplasia, lateral trochlea inclination as the highest rated measurement. Trochlear depth and trochlear facet asymmetry were also used.