 Axial fat-suppressed proton density-weighted magnetic resonance imaging (MRI) shows trochlear dysplasia and the measurements taken for determining the trochlear depth ([59 + 58.1] ÷ 2) – 56.5 = 2.05 mm. An axial MRI 3 cm above the joint line is needed to calculate the trochlear depth. The average distance of the medial and lateral facets from a line tangential to the femoral condyles is subtracted from the distance of the trochlear groove to that same tangential line. A value <3 mm is considered shallow and consistent with trochlear dysplasia.