[The measurement of the tibial tuberosity. Patella groove distanced technique and results (author's transl)].

The line between the summit of the tibial tuberosity and the bottom of the trochlea groove as seen on a radiograph taken with the knee in 30 degrees of flexion and neutral rotation is indicative of the valgus position of the quadriceps mechanism at the moment of engatement of the patella in the groove. The authors stress the technical requirements to obtain the radiograph which permits this measurement. Measurement of a group of normal knees and of two groups of knees presenting with known patello-femoral pathology (lateral patello-femoral arthrosis and current dislocation of the patella) are given. In the study of distrubance of the patello-femoral articulation, this measurement provides information of theoretical and therapeutic interest.