Fig. 1

Outlines of the tibial cortex at each level. The six intersection points of the three lines and the tibial contour were named as the QMA, QMP, CA, CP, QLA, and QLP at each resection level. QMA, quarter-medial-anterior point; QMP, quarter-medial-posterior point; CA, central-anterior point; CP, central-posterior point; QLA, quarter-lateral-anterior point; QLP, quarter-lateral-posterior point