Flat feet

Flat feet in an adult is a progressive, symptomatic deformity resulting from gradual stretching of the posterior tendon as well as the ligaments that support the arch of the foot.

In children flat feet are not painful but for the adult, pain occurs because soft tissues have been torn. The deformity progresses or worsens because once the vital ligaments and posterior tibial tendon are lost, nothing can take their place to hold up the arch of the foot. Contributing factors increasing the risk of adult flatfoot are diabetes, hypertension and obesity.

The person with flat feet has greater load placed on the posterior tibial tendon which is the main tendon unit supporting up the arch of the foot. As we age the muscle strength decrease as well as tendons and ligaments. The blood supply diminishes to tendons with aging as arteries narrow. Heavy obese patients have more weight on the arch and greater narrowing of arteries due to atherosclerosis. In some people the posterior tibial tendon finally gives out or tears. The bones of the arch then move out of position with body weight pressing down from above. The foot rotates inward at the ankle in the movement called pronation. The arch appears collapsed and the heel bone is tilted to the inside. The deformity can progress until the foot literally dislocates outward from under the ankle joint.

This is from www.PodiatryNetwork.com