MRI-Based Morphometric Analysis of the Femoral Intercondylar Notch and Its Association With Traumatic Anterior
Prasad Soraganvi1, Praveen Kumar Venkataraman1, Surendra Babu1
1Department of Orthopaedics, St. Peter's Medical College, Hospital and Research Institute, Hosur, IND.
Introduction:
Femoral intercondylar notch morphology has been proposed as an intrinsic anatomical risk factor for anterior cruciate ligament (ACL) injury. Magnetic resonance imaging (MRI) provides a reliable and non-invasive method for assessing notch morphometry and related parameters associated with ACL injury risk.
Methods:
A prospective observational study was performed on 108 patients aged 18-45 years who underwent knee MRI following traumatic injury. Participants were divided into a normal ACL group (n = 54) and an ACL tear group (n = 54). Morphometric parameters, including notch width (NW), bicondylar width (BW), NW index (NWI), notch angle, and notch shape, were measured on standardized axial MRI images. Continuous variables were analyzed using independent t-tests, and categorical variables were compared using the chi-square (χ²) test.
Results:
The ACL tear group demonstrated a significantly lower mean NWI compared with the normal ACL group (0.2394 vs. 0.2637; p = 0.00001). Notch angle was also significantly smaller in patients with ACL tears (49.74° vs. 52.33°; p = 0.0056). A-shaped notch morphology showed a strong association with ACL rupture, whereas U-shaped and Ω-shaped notches were more frequently observed in knees with intact ACLs. Age did not show a significant association with ACL injury, while male predominance and right-sided involvement were more common in the ACL tear group.
Conclusion:
Stenotic femoral intercondylar notch characteristics, including reduced NWI, smaller notch angle, and A-shaped configuration, are significantly associated with traumatic ACL injury. MRI-based morphometric evaluation may aid in identifying individuals at increased risk of ACL rupture and support targeted preventive strategies.
