An association between femoral trochlear morphology and non-contact anterior cruciate ligament total rupture: a retrospective MRI study

The present study aims to investigate the association of the femoral trochlear morphology with the risk of ACL injury and whether this can be considered an additional risk factor in this clinical table. This is a retrospective case–control study with 93 patients, 41 patients with ACL total rupture (ACL-TR), and 52 patients without ACL injury who underwent knee magnetic resonance imaging (MRI) between January 2013 and January 2016. The femoral trochlear morphology was evaluated at the proximal and distal levels from the axial knee MRI. The morphological features of the trochlea using sulcus angle, sulcus depth, condylar heights, trochlear sulcus height, percentage of condyles and trochlear sulcus height to transepicondylar width, and lateral and medial trochlear inclination were evaluated. The notch width index was measured on the coronal MR images for notch stenos. ACL-TR group had a significantly higher sulcus angle (p = 0.00–0.001) and lower sulcus depth (p = 0.00–0.002) than the control group at both levels. Femoral trochlea had morphometric differences between genders. NWI was lower in the ACL-TR group than the control group (control 0.273; ACL-TR 0.247), and there was a statistically significant difference (p = 0.00). This study was shown that the difference in morphology between the trochlear sulcus of patients with normal and ACL injuries should be taken into account in order to increase awareness of ACL injuries. We observed that mild trochlear dysplasia may cause intercondylar notch stenosis rather than changing the localization of the patella. Studies are needed regarding the effect of trochlear dysplasia on ACL.