Correlation of the intercondylar notch width of the femur to the width of the anterior and posterior cruciate ligaments

The purpose of this study was to determine if a correlation exists between the intercondylar notch width (NW) of the femur and the width of the anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL). A study group of 124 consecutive patients (mean age 36.6 +/- 15.2 years; 67 men, 57 women) underwent a magnetic resonance imaging evaluation for knee pain but did not have an ACL or PCL tear or arthrosis. A T2 weighted coronal cut was identified and was located at the middle of the tibial spine, which represented the plane where the ACL and PCL cross each other when the knee is in 10 degrees of flexion. The NW and the width of the ACL and PCL were measured at the level of the middle of the popliteal hiatus on a physician-independent console that allowed for digital measurements in millimeters. Our results showed a statistically significant correlation between NW and ACL width (r = 0.87; P < 0.001) and between NW and PCL width (r = 0.75; P < 0.001). The mean ACL width was 6.3 +/- 1.4 mm (range 3-10 mm). The mean PCL width was 10.2 +/- 2.0 mm (range 6-17 mm). The mean ACL width was 5.7 +/- 1.1 mm for women and 7.1 +/- 1.2 mm for men (P < 0.001). The mean PCL width was 9.5 +/- 1.7 mm for women and 10.9 +/- 3.0 for men (P < 0.001). Our results indicate that NW correlates with ACL and PCL width. In addition, ACL and PCL widths are narrower in women than men.