The results of the study suggest that children be encouraged to play barefooted on various surfaces of terrain and that slippers and sandals are less harmful compared to closed-toe shoes. It appeared that closed-toe shoes greatly inhibited the development of the arch of the foot more so than slippers or sandals. This conclusion may be a result of the notion that intrinsic muscle activity of the arch is required to prevent slippers and sandals from falling off the childs foot. In children with few symptoms orthotics are not recommended. Adults
Flat feet can also develop as an adult ("adult acquired flatfoot") due to injury, illness, unusual or prolonged stress to the foot, faulty biomechanics, or as part of the normal aging process. This is most common in women over 40 years of age. Known risk factors include obesity, hypertension and diabetes. Flat feet can also occur in pregnant women as a result of temporary changes, due to increased elastin (elasticity) during pregnancy. However, if developed by adulthood, flat feet generally remain flat permanently. If a youth or adult appears flatfooted while standing in a full weight bearing position, but an arch appears when the person plantarflexes, or pulls the toes back with the rest of the foot flat on the floor, this condition is called flexible flatfoot.
Treatment may include foot gymnastics or other exercises as recommended by a podiatrist or physical therapist. In cases of severe flat feet, orthoses should be used through a gradual process to lessen discomfort. Over several weeks, slightly more material is added to the orthosis to raise the arch. These small changes allow the foot structure to adjust gradually, as well as giving the patient time to acclimatise to the sensation of wearing orthoses. In some cases, surgery can provide lasting relief, and even create an arch where none existed before; it should be considered a last resort, as it is usually very time-consuming and costly. A minimally-invasive surgical intervention involving a small implant is also available. The implant is inserted into the sinus tarsi and prevents the calcaneus and talus from sliding relative to each other. This prevents the sinus tarsi from collapsing and thus prevents the external symptom of the fallen arch from occurring. Athletic performance
The effects of flat feet fall under two categories, which are asymptomatic and symptomatic. Individuals with rigid flat feet tend to exhibit symptoms such as foot and knee tendinitis, and are recommended to consider surgical options when managing symptoms. Individuals with flexible flat generally exhibit asymptomatic effects in response to their flat feet.According to AAP news and journal gateway, being flexibly flat-footed does not impede athletic performance.It is generally assumed by running professionals (primarily including some physical trainers, podiatrists, and shoe manufacturers) that a person with flat feet tends to overpronate in the running form.