The joints in your body that bear weight (ankles, knees, hips, pelvis, low back, neck) are like links in a chain. If your feet aren't balanced, every joint (and connecting muscles, tendons and ligaments) above may become injured over time due to unnatural twists and strain on your body. Pain may occur because of these postural imbalances.

In addition, every time your feet hit the ground, a shock wave travels all the way through your body. If your feet are balanced, they can absorb much of that shock. But if they're not in balance, over time that shock can cause you additional stress/strain.