Knee ligament attachment coordinates are essential in developing a model of the passive constraints of the joint as well as evaluating ligament behavior. Several methods for making measurements of the ligament attachment sites have been reported. One proposed method asserted that high bone density can be used to locate ligament insertion sites. In order to examine if thresholding of bone density can be used to identify ligament insertion sites, CT scans of the femur and tibia-fibula of a cadaver were taken with and without the ligament attachment sites marked. Scans were viewed with a computer program to see if a recognizable and geometrically consistent distribution of higher bone density existed near the ligament insertion sites. The results show that for regions of higher bone density to be used to identify ligament insertion sites, different threshold values for each ligament need to be used, different threshold values for different points along the femur need to be used, and it is sometimes necessary to know the approximate location of the ligament insertion site to locate a region of higher bone density near the insertion site.