Topography of the femoral attachment of the posterior cruciate ligament.

BACKGROUND The success of posterior cruciate ligament reconstruction has varied. The objective of this study was to determine quantitatively and qualitatively the topography and osseous landmarks of the femoral footprints of the anterolateral and posteromedial bundles of the posterior cruciate ligament in order to enhance repair. METHODS Twenty unpaired knees from twenty human cadavers were evaluated. The surface features of the femoral footprints of the anterolateral and posteromedial bundles of the posterior cruciate ligament were studied by means of macroscopic observation and three-dimensional laser photography. RESULTS We observed, both visually and with three-dimensional laser photography, an osseous prominence located proximal to the femoral footprint of the posterior cruciate ligament in eighteen of the twenty human knees. This osseous landmark, denominated the "medial intercondylar ridge," determined the proximal border of the posterior cruciate ligament footprint. In eight of the twenty knees, we observed a small osseous prominence between the anterolateral and posteromedial bundles of the posterior cruciate ligament. A clear change in the slope of the femoral footprint of the posterior cruciate ligament was seen between the anterolateral and posteromedial bundles. The average area of the posterior cruciate ligament footprint (and standard deviation) was 209 +/- 33.82 mm(2), the average area of the anterolateral bundle was 118 +/- 23.95 mm(2), and the average area of the posteromedial bundle was 90 +/- 16.13 mm(2). CONCLUSIONS The femoral footprint of the posterior cruciate ligament has a unique surface anatomy, with a medial intercondylar ridge being frequently present and a medial bifurcate ridge being less frequently present.