Evaluation of femoral condyle volumes in patients with trochlear dysplasia: a pilot study

Abstract

To examine the volumes of the medial and lateral femoral condyles and the trochlear groove, and to determine their relationship with trochlear dysplasia. Computed tomography images of the knees of 21 patients with trochlear dysplasia and 18 healthy individuals were analysed retrospectively. According to the modified Dejour classification, the degree of trochlear dysplasia was recorded, such as type A trochlea being low-grade dysplasia and types B, C, and D trochlea being high-grade dysplasia. Volume of the trochlear groove and medial and lateral femoral condyles were calculated using the three-dimensional (3D) volume-rendering method. The volumes of lateral condyle, medial condyle, and trochlear groove were statistically significantly lower in patients with trochlear dysplasia when compared to healthy participants. When compared according to Dejour types, all parameters were statistically significantly lower in both high- and low-grade dysplasia patients (p<0.05). The correlation between femoral condyle volumes and trochlear groove volume was low in the control group, but there was a moderate positive correlation in the patient group (r=0.50-0.75, p<0.05). In trochlear dysplasia, the volume of the trochlear groove decreases and hypoplasia may occur in both lateral femoral and medial femoral condyles. Therefore, hypoplasia of only one condyle should not be interpreted as trochlear dysplasia. A holistic approach to patients is required.