The final paper in this section where Daniel Green is going to talk about asymmetry of the medial lateral condyles and its relationship to ACL injury risk in a pediatric group. Thanks Daniel. Thank you Dr. Parker. Thanks for the privilege and honor to present this pretty simple study about asymmetry of the posterior femoral condyles in our kids that present with ACL tears. I'll acknowledge my co-workers, try to get the thing to go forward, this one, some disclosures. So everybody in this audience knows the long list of non-modifiable and modifiable risk factors associated with ACL tear. We just heard Dr. Volker talk about laxity as being one of the non-modifiable risk factors. We've been studying these anatomic risk factors for a while, looking at, demonstrating what Dr. Tuca, the small notch width and notch size is at increased risk for pediatric ACL tear. We also confirmed that the posterior tibial slope is seen in the pediatric group with an increased risk for ACL tear. And we've also shown recently that severe Osgood-Schlatter's may lead to an increased posterior tibial slope. So we wanted to continue that line of research looking at anatomic risk factors for non-modifiable anatomic reasons for an ACL tear, and we thought we'd focus on the posterior aspect of the knee, the posterior femoral condyles. This important geometry really influences the kinematics of the knee and knee flexion. We wanted to look to see if there was any difference in morphology of the posterior femoral condyles in our kids with ACL tears. So we looked at our patients aged 6 to 18 who had a preoperative MRI with an ACL, and then we did case-based cohort based on sex, age, and laterality. So we matched the group to controls. We measured the medial and lateral anterior-posterior condylar height for each study, and we also looked at version. So we had 36 pediatric ACL patients matched age, sex, size, age, and sex 36 times. Average age was 13. What did we find? That the medial posterior condylar height was always greater than the lateral, but in our ACL group, the difference between medial and lateral was nearly 2 millimeters different, and this was statistically significant. We also found a subtle difference in version, with external distal femoral version noted to be greater in the ACL group. So we could see that in this increased asymmetry of the medial and lateral posterior femoral condyles appears to be associated with pediatric ACL tears. Now why is this important? You can imagine driving around your car, if you have the left side of your car and the right side of your car, different size tires, your car is not going to behave right. You can imagine as the knee goes into flexion, with the larger medial posterior femoral condyle at 90 degrees, that knee is going to be in more valgus. And so we believe that this may be a reflection, as the knee goes into flexion, that there's structural or anatomic dynamic valgus in the knee. So perhaps we should add asymmetry of the posterior femoral condyle to our list of non-modifiable risk factors. And I thank you for your attention.

Daniel Green

asymmetry

medial posterior condyle

lateral posterior condyle

ACL injury risk