Intercondylar shelf angle: a new method to determine race from the distal femur

This study documents racial variation in the intercondylar shelf angle. The intercondylar shelf is actually the "roof" of the intercondylar notch, and on a lateral radiograph of the femur this is a distinctive feature called Blumensaat's Line. The angle between Blumensaat's Line and the posterior shaft of the femur can be quickly and easily measured. Variations in this angle are not dependent on the size of the femur, nor is the angle affected by arthritis in the notch or by trauma to the articular surfaces. Even fragmentary femora can be measured. This is a non-invasive technique that can be used in skeletal cases as well as cases where there are intact soft tissues.