Ground reaction force

If a patient demonstrates severe hyperlordosis of the L-spine, while standing what affect occurs at the knee joint?

You can imagine that if the patient is in hyperlordosis their center of gravity shifts more posterior and the center of pressure is likely more towards the hind foot.  (Try hyperextending your L-spine and see where you feel the most pressure on the plantarsurface of your feet.)   Next draw a line connecting these two points.  This line falls posterior to the knee joint causing a knee flexion moment.