[The Tibial Slope. Proposal for a Measurement Method]

The posterior inclination of the tibial plateaus relative to the longitudinal axis of the bone, also called tibial slope, is important to know for the pathology of the cruciate ligaments and to lay some knee prostheses. We have chosen a reproducible method to measure it, on the basis of a large radiograph of the lower limb. A radio-anatomical analysis of the morphology of the tibia has first been carried out to properly choose axes that are easy to find and useful in practice. The accuracy of the measurement is to within one degree. In adults, the slope ranges from 0 to 18 degrees, according to the subjects, with variations form one knee to the other.