INTRAOPERATIVE AND POSTOPERATIVE INSERTIO N CONTROL OF ACL GRAFTS - ARADIOLOGICAL MEASURING METHOD (QUADRANT METHOD)

The best proximal insertion for an ACL graft is an anatomic insertion. The anatomic landmarks of this insertion area are well known, but it is sometimes difficult to find these anatomic landmarks during the ope ration. Thus, it is desirable to have an objective method to control t he insertion. This study was undertaken because no description is avai lable how you can localize the projection of the anatomic ALC insertio n exactly in an X-ray picture. We dissected ten human cadaveric knees with intact ACLs. The most ventral, dorsal, distal and proximal border s of the insertion area were marked with 4 K-wires. The K-wires were s hortened exactly on the bone border of the intercondylar space. Then t he knees were X-rayed in a strictly lateral position. Thus, the shorte ned ends of the K-wires determined the projection of the ACL insertion in the X-ray picture. The center of this marked area was called point K. Then we determined 4 distances in the X-ray picture: distance t: t he sagittal diameter of the lateral condyle, measured along the Blumen saat line distance h: the maximal height of the notch distance a: the distance between K and the dorsal border of the condyle, measured alon g t distance b: the distance between t and K, measured on a perpendicu lar line on t Distance a is a partial distance of t and distance b is a partial distance of h. Because of varying projection factors and var ying knee sizes, absolute values of these distances are not helpful. T his is the reason why we expressed a and b as a proportion of t and h. Distance a was measured 24.8% of distance t. Distance b was measured 28.5% of distance h. The maximal deviation of a and b was 2.2% and 2.5 %. Therefore, you can say: In a strictly lateral X-ray picture the dis tance of K (midpoint of proximal ACL insertion) from the dorsal border of the condyle is 24.8% of the whole diameter of the condyle, and the distance of K from the roof of the notch is 28.5% of the notch-height . This method does not depend on the size of the knee and the distance between the X-ray unit and the knee. The only condition is that the X -ray of the knee must be strictly lateral. This method is easy to hand le and is reproducible. It can be used intraoperatively if the surgeon is not sure about the right insertion or if the anatomic landmarks ca nnot be seen exactly. It can be used postoperatively for documentation of the right position of the substitute. It can be used to find out t he possible reason for rupture of a transplant (insertion too ventral) before the revision operation.