Intercondylar notch size and anterior cruciate ligament injuries in athletes. A prospective study.

Published reports agree that there is a strong association between intercondylar notch stenosis and anterior cruciate ligament injuries. In a previously published retrospective study on bilateral anterior cruciate ligament injuries and associated intercondylar notch stenosis, we formulated the notch width index to measure and compare intercondylar notch width. The purpose of this prospective study was to establish a normal range for the notch width index and to correlate intercondylar notch size and anterior cruciate ligament injuries. We gathered data on 902 high school athletes, including range of motion, thigh girth, ligament stability and intercondylar notch width using the notch width index. The population was then followed prospectively and anterior cruciate ligament injuries were recorded and correlated with notch width index in a blind manner. Two-year results showed that the overall anterior cruciate ligament injury rate was 3%. The normal intercondylar notch ratio was 0.231 +/- 0.044. Intercondylar notch width index for men was larger than that for women. Athletes sustaining noncontact anterior cruciate ligament tears have statistically significant intercondylar notch stenosis (notch width index, 0.189). Ten of 14 athletes with noncontact anterior cruciate ligament injuries had a notch width index that was at least 1 SD below the mean. Athletes with contact anterior cruciate ligament injuries had a mean of 0.233. We conclude that athletes with a stenotic intercondylar notch are at significantly greater risk for sustaining noncontact anterior cruciate ligament injury.