In flat foot, the knee is transitioning from what position?

In the context of flat foot, or pes planus, there is an important relationship between the position of the knee and the alignment of the foot. During the transition to a flatfoot position, the knee typically moves from a position of higher flexion (approximately 20 degrees) towards extension.

This transition is significant because as the foot pronates, the knee adapts to maintain alignment and stability during weight-bearing activities. The movement of the knee toward extension (often when the foot is flat on the ground) allows for proper function and weight distribution during gait.

In flatfoot, the arch of the foot collapses, leading to increased pronation and causing the knee to experience a compensatory change in angle to maintain functional mechanics. Thus, the correct choice reflects this dynamic adjustment that occurs at the knee as the foot transitions to a flat position, moving from approximately 20 degrees of flexion and working toward extension to support stability and mobility.