|  |  |  |  | The arch is the main supportive structure of your foot. If this arch loses strength, the bony framework begins to collapse, causing your foot to flatten. Like a sagging bridge, the weakness in the middle, strains the joints at both ends of your foot. |  |  | Causes There are many causes of flatfeet. Some people are born with them, others acquire flatfeet as a result of arthritis, trauma, or musculoskeletal disorders. Overuse or repeated pounding on hard surfaces can also weaken the arch. |  |  | Symptoms Discomfort from flatfeet often doesn't appear for years. At some point, pain may be felt, and walking may become awkward as increasing strain is put on your feet and calves. |  |  | Related Problems The excess strain from flatfeet can cause other foot problems such as hammertoes, bunions, heel spurs, arch strain, corns, neuromas, and sagging joints. Flatfeet can also affect other parts of the body, causing fatigue, pain, or stiffness in the ankles, knees, hips, or lower back. |  | | |