What Is the Cause of Flat Feet?
When you make wet footprints on the bathroom floor, you will see that there are blank patches in the middle between the toe marks and the heel marks. This is because the middle parts of the feet are raised off the ground by two sets of muscles, called the tibial and the peronal muscles which make the arches of the feet. If these muscles weaken, the feet spread out and the arches sink to the ground.
The footprints are flat, with no gaps in the middle. This is called having flat feet, (also called pes planus or fallen arches). Arches can also fall over time. Years of wear and tear can weaken the tendon that runs along the inside of your ankle and helps support your arch.
Sometimes people get flat feet because their jobs keep them standing around too much. Policemen, waitresses and nurses often suffer from flat feet. The cure is exercise which tightens up the muscles again. Supports to be put inside shoes are worse than useless. They make the muscles slacken, weaker instead of stronger.
A flat foot is normal in infants and toddlers, because the foot’s arch hasn’t yet developed. Most people’s arches develop throughout childhood, but some people never develop arches. This is a normal variation in foot type, and people without arches may or may not have problems.
Some children have flexible flatfoot, in which the arch is visible when the child is sitting or standing on tiptoes, but disappears when the child stands. Most children outgrow flexible flatfoot without problems.
A flat foot is a postural deformity in which the arches of the foot collapse, with the entire sole of the foot coming into complete or near-complete contact with the ground. Some individuals (an estimated 20–30% of the general population) have an arch that simply never develops in one foot (unilaterally) or both feet (bilaterally).
There is a functional relationship between the structure of the arch of the foot and the biomechanics of the lower leg. The arch provides an elastic, springy connection between the forefoot and the hind foot. This association safeguards so that a majority of the forces incurred during weight bearing of the foot can be dissipated before the force reaches the long bones of the leg and thigh.
In pes planus, the head of the talus bone is displaced medially and distal from the navicular. As a result, the spring ligament and the tendon of the tibialis posterior muscle are stretched, so much so that the individual with pes planus loses the function of the medial longitudinal arch (MLA).
If the MLA is absent or nonfunctional in both the seated and standing positions, the individual has “rigid” flatfoot. If the MLA is present and functional while the individual is sitting or standing up on their toes, but this arch disappears when assuming a foot-flat stance, the individual has “supple” flatfoot. This latter condition can be correctable with well-fitting arch supports.