The human arch develops in infancy and early childhood as part of normal muscle, tendon, ligament and bone growth.

Children with flat feet are at a higher risk of developing knee, hip, and back pain.

[3] As a symptom itself, flat feet usually accompany genetic musculoskeletal conditions such as dyspraxia,[4] ligamentous laxity or hypermobility.

A systematic review and meta-analysis study by Xu, et.al., found that urban sedentary boys, aged 6–9, were frequently diagnosed with flatfeet.

One medical study in India with a large sample size of children who had grown up wearing shoes and others going barefoot found that the longitudinal arches of the bare-footers were generally strongest and highest as a group, and that flat feet were less common in children who had grown up wearing sandals or slippers than among those who had worn closed-toe shoes.

Focusing on the influence of footwear on the prevalence of pes planus, the cross-sectional study performed on children noted that wearing shoes throughout early childhood can be detrimental to the development of a normal or a high medial longitudinal arch.

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.

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 child's foot.

[citation needed] Research has shown that tendon specimens from people who have adult-acquired flat feet show evidence of increased activity of proteolytic enzymes.

In more extreme cases, known as a kinked flatfoot, the entire inner edge of the footprint may actually bulge outward, where in a normal to high arch this part of the sole of the foot does not make contact with the ground at all.

The results of the study indicated that, while barefoot, subjects activated additional lower-leg muscles to complete an exercise that resisted foot adduction.

However, when the same subjects performed the exercise while wearing arch supporting orthotics and shoes, the tibialis posterior was selectively activated.

Such discoveries suggest that the use of shoes with properly fitting arch-supporting orthotics will enhance selective activation of the tibialis posterior muscle, thus acting as an adequate treatment for the undesirable symptoms of pes planus.

Rheumatoid arthritis can destroy tendons in the foot (or both feet), which can cause this condition, and untreated can result in deformity and early onset of osteoarthritis of the joint.

[17] Treatment of flat feet may also be appropriate if there is associated foot or lower-leg pain, or if the condition affects the knees or the lower back.

These small changes allow the foot structure to adjust gradually, as well as giving the patient time to acclimatize to the sensation of wearing orthoses.

[24] No current studies have been successful in fully ascertaining the long-term detriments to health caused by the overexertion (necessary for athletes/soldiers performing with flat feet) and other compensating measures commonly enacted by the body during bipedal movement.