Differences in femoral notch anatomy between men and women - A magnetic resonance imaging study

Background: Research has shown that variations in femoral intercondylar notch morphometry may be a predisposing factor for noncontact anterior cruciate ligament injury. Hypothesis: There are anatomic differences in the anterior cruciate ligament and femoral notch between men and women. Study Design: Descriptive anatomic study. Methods: Using magnetic resonance imaging, we performed a three-dimensional analysis of the femoral intercondylar notch morphometry to look for differences in femoral notch and anterior cruciate ligament volumes between men and women. Axial plane magnetic resonance imaging scans were performed on 96 knees in 48 asymptomatic subjects. Digital measurements were taken of femoral notch area, anterior cruciate ligament area, notch width, and bicondylar width, within defined parameters of the femoral notch. The notch and anterior cruciate ligament volumes were then calculated. Analysis of variance was performed using sex, height, and weight as covariates. Results: The volume of the femoral notch was found to be statistically smaller in women compared with men; this difference was primarily related to height. A similar relationship was found for anterior cruciate ligament volume. A statistically significant correlation was found between femoral notch volume and anterior cruciate ligament volume; patients with smaller notches also had smaller anterior cruciate ligaments. Conclusions: Our results suggest that there is a difference in femoral notch and anterior cruciate ligament volume between men and women, which, in turn, is related to differences in height and weight.