Pes Planus

Pes Planus – Flat Feet

From A.D.A.M. Medical Encyclopedia

Pes Planus – Causes, Incidence & Risk Factors – Signs & Tests – Symptoms – Treatment

Expectations (Prognosis) – Complications – Calling Your Health Care Provider

From Wikipedia – The Free Encyclopedia

Flat Feet – Arch Development in Children – Flat Feet in Adults – Pathophysiology

Flatfoot Related Conditions – Diagnosis – Flexible Flatfoot – Treatment – Running

Flatfeet & the Military

—Flat Feet

Pes planovalgus; Fallen arches; Pronation of feet; Pes planus

Flat feet (pes planus) is a condition in which the foot does not have a normal arch when standing.

—Causes, Incidence & Risk Factors

Flat feet are a common condition. In infants and toddlers, they are normal.
Flat feet occur because the tissues holding the joints in the foot together (called tendons) are loose. 
In infants and babies, the fat in the foot is also a factor.
As children grow older, these tissues tighten and form an arch, 
most often by the time the child is 2 or 3 years old.

By adulthood, most people have normal arches. 
However, in some people this arch may never form.
Aging, injuries, or illness may harm the tendons 
and cause flat feet to develop in a person who has already formed arches. 
This type of flat foot may only be on one side.

Rarely, painful flat feet in children may be caused by a condition in which 
two or more of the bones in the foot grow or fuse together. 
This condition is called tarsal coalition.


Most flat feet do not cause pain or other problems.
At times, foot pain, ankle pain, or lower leg pain are present (especially in children). 
They should be evaluated by a health care provider.
Adults may notice some symptoms. 
Their feet may become achy or tired when standing for long periods of time or after playing sports.

—Signs & Tests

In people with flat feet, the instep of the foot comes in contact with the ground when they stand.
The health care provider will ask you to stand on your toes. 
If an arch forms while you are standing on your toes, 
the flat foot is called flexible. No treatment or further work-up is needed.
If the arch does not form with toe-standing (called rigid flat feet), 
or if there is pain, other tests may be needed, including:

  • CT scan to look at the bones in the foot
    • MRI scan to look at the tendons in the foot
    • X-ray of the foot


Once your health care provider has examined your child, 
no treatment is needed for flat feet that are not causing any pain or problems walking.

  • Your child’s feet will grow and develop the same, 
    whether special shoes, shoe inserts, heel cups, or wedges are used.
  • Your child may walk barefoot, run or jump, 
    or do any other activity without making the flat feet worse.
    In older children and adults, flexible flat feet that are painless and do not cause problems 
    with walking do not need further treatment once a health care provider has evaluated them.

If you have pain due to flexible flat feet, the following may help:

  • An off-the-shelf or custom-made orthotic (arch-supporting insert in the shoe)
    • Special shoes

Rigid or painful flat feet require evaluation by a health care provider. 
The treatment depends on the cause of the flat feet.
For tarsal coalition, treatment starts with rest and possibly a cast. 
If this does not improve the pain, surgery may be needed.

In more severe cases, surgery may be needed to:

  • Clean or repair the tendon
    • Fuse some of the joints of the foot into a corrected position

Flat feet in older adults can be treated with pain relievers, orthotics, and sometimes surgery.

—Expectations (Prognosis)

Most cases of flat feet are painless and do not cause any problems or need treatment.
Some causes of painful flat feet can be successfully treated without surgery, 
but surgery is the last option to relieve pain in some cases.
Patients who need to have surgery often report improvement in pain and function.


Flat feet rarely cause any complications except pain.
Possible problems after surgery include:

  • Failure of the fused bones to heal
    • Foot deformity that does not go away
    • Infection
    • Loss of ankle movement
    • Pain that does not go away

—Calling Your Health Care Provider

Call your health care provider if you experience persistent pain in your feet 
or your child complains of foot pain or lower leg pain.


Most cases are not preventable.

From Wikipedia – The Free Encyclopedia

—Flat Feet

– also called Pes Planus – where Pes is Foot and Planus is Flat = Flat Foot
– also known as Fallen Arches

a medical condition in which the arch of the foot collapses, 
with the entire sole of the foot coming into complete or near-complete contact with the ground.
In other words, the foot does not have a normal arch when standing.

In some individuals (an estimated 20–30% of the general population) 
the arch simply never develops in one foot (unilaterally) or both feet (bilaterally).

—Arch Development in Children

Flat feet of a child are usually expected to develop into high or proper arches.
The appearance of flat feet is normal and common in infants, 
partly due to “baby fat” which masks the developing arch 
and partly because the arch has not yet fully developed.

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

Training of the feet, especially by foot gymnastics and going barefoot on varying terrain, 
can facilitate the formation of arches during childhood, 
with a developed arch occurring for most by the age of four to six years.

Flat arches in children usually become proper arches and high arches 
while the child progresses through adolescence and into adulthood.

A survey of 297 school children at Allahabad, Uttar Pradesh, India revealed that; 
40.32% of children under 5, 
22.15% of children between 5 and 10, and
15.48% of children older than 10 
suffered bilateral (both feet) flat foot.

As long as the foot is still growing, 
it may be possible that a lasting arch can be created.

Because young children are unlikely to suspect or identify flat feet on their own, 
it is a good idea for parents or other adult caregivers to check on this themselves.

Besides visual inspection, 
parents should notice whether a child begins to walk oddly or clumsily, 
for example, on the outer edges of the feet, or to limp, during long walks, 
and to ask the child whether he or she feels foot pain or fatigue during such walks.

Children who complain about calf muscle pains or any other pains around the foot area, 
may be developing or have flat feet. 
Pain or discomfort may also develop in the knee joints.

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 barefooters 
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.

A recent randomized controlled trial found no evidence 
for the efficacy of treatment of flat feet in children 
either for expensive prescribed orthoses (shoe inserts) 
or less expensive over-the-counter orthoses.

—Flat Feet in 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, 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.


Research has shown that tendon specimens from people who suffer from adult acquired flat feet 
show evidence of increased activity of proteolytic enzymes. 
These enzymes can break down the constituents of the involved tendons and cause the foot arch to fall. 
It is possible that in future these enzymes will become targets for new drug therapies.

—Flatfoot Related Conditions

Rigid flatfoot is a condition where the sole of the foot is rigidly flat even when a person is not standing, 
often indicating a significant problem in the bones of the affected feet, 
and can cause pain in about a quarter of those affected.

Other flatfoot-related conditions, such as various forms of tarsal coalition 
(two or more bones in the midfoot or hindfoot abnormally joined) 
or an accessory navicular (extra bone on the inner side of the foot) should be treated promptly, 
usually by the very early teen years, before a child’s bone structure firms up permanently as a young adult. 
Both tarsal coalition and an accessory navicular can be confirmed by x-ray.

Rheumatoid Arthritis can destroy tendons in the foot (or both feet) 
which can cause the development of flat feet. 
If left untreated, it can result in foot deformity 
and early onset of Osteoarthritis in the joints of the foot.
Such a condition can cause severe pain and considerably reduced ability to walk, even with orthoses. 
Ankle fusion is usually recommended in such situations.


Many medical professionals can diagnose a flat foot 
by examining the patient standing or just looking at them. 
On going up onto tip toe the deformity will correct 
when this is a flexible flat foot in a child with lax joints. 
Such correction is not seen in the adult with a rigid flat foot.

An easy and traditional home diagnosis is the “wet footprint” test, 
performed by wetting the feet in water and then standing on a smooth, level surface 
such as smooth concrete or thin cardboard or heavy paper. 
Usually, the more the sole of the foot that makes contact 
(leaves a footprint), the flatter the foot.

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.

—Flexible Flatfoot

If a youth or adult appears flatfooted while standing in a full weight bearing position, 
but an arch appears when the person dorsiflexes the foot,
(stands on heel or pulls the toes back with the rest of the foot flat on the floor), 
this condition is called flexible flatfoot.

This is not a true collapsed arch, as the medial longitudinal arch is still present
and the Windlass mechanism still operates; 
this presentation is actually due to excessive pronation of the foot (rolling inwards), 
although the term ‘flat foot’ is still applicable as it is a somewhat generic term.


Most flexible flat feet are asymptomatic, and do not cause pain. 
In these cases, there is usually no cause for concern, 
and the condition may be considered a normal human variant.

Going barefoot, particularly over terrain such as a beach where muscles are given a good workout, 
is good for all but the most extremely flatfooted, 
or those with certain related conditions such as plantar fasciitis.

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 barefooters 
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.

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

Treatment may include using Orthoses such as an arch support, foot gymnastics or other exercises 
as recommended by a podiatrist/orthotist 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.

Once prescribed, orthoses are generally worn for the rest of the patient’s life. 
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.

Muscular training of the feet, while generally helpful, 
will usually not result in increased arch height in adults, 
because the muscles in the human foot are so short 
that exercise will generally not make much difference, 
regardless of the variety or amount of exercise. 
However, as long as the foot is still growing, 
it may be possible that a lasting arch can be created.


It is generally accepted by professionals that a person with flat feet 
tends to overpronate in his or her running form. 
Pronation is a natural form of shock absorption during running and walking, 
when the ankle rolls inward and the weight distribution in the foot shifts medially.

Overpronation is excessive pronation; it disrupts the alignment of the leg and may result in injuries 
due to over-stressing of the knee and leg.

With normal, or neutral running shoes, a person who overpronates in his or her running form 
may be more susceptible to shin splints, back problems, and tendonitis in the knee.

Running in shoes with extra medial support or using special shoe inserts and orthoses, 
may help correct one’s running form by reducing pronation and may reduce risk of injury.

—Flatfeet and the Military

Flat feet were formerly a physical-health reason for service-rejection in many militaries. 
However, three military studies on asymptomatic adults, 
suggest that persons with asymptomatic flat feet are at least as tolerant of foot stress 
as the population with various grades of arch. 
Asymptomatic flat feet are no longer a service disqualification in the U.S. military.

Studies analyzing the correlation between flat feet and physical injury in soldiers have been inconclusive, 
but none suggest that flat feet are an impediment, 
at least not in soldiers who reached the age of military recruitment without prior foot problems. 
Instead, in this population, there is a suggestion of more injury in high arched feet.

A 2005 study of Royal Australian Air Force recruits that tracked 
the recruits over the course of their basic training 
found that neither flat feet nor high arched feet had any impact 
on physical functioning, injury rates or foot health. 
If anything, there was a tendency for those with flat feet to have fewer injuries.

Another study of 287 Israel Defense Forces recruits found that those with high arches suffered 
almost four times as many stress fractures as those with the lowest arches.

A later study of 449 U.S. Navy special warfare trainees found no significant difference 
in the incidence of stress fractures among sailors and Marines with different arch heights.

Three studies of military recruits have shown no evidence of later increased injury, 
or foot problems, due to flat feet, in a population of people 
who reach military service age without prior foot problems. 
However, these studies cannot be used to judge possible future damage 
from this condition when diagnosed at younger ages. 
They also cannot be applied to persons whose flat feet are associated with foot symptoms, 
or certain symptoms in other parts of the body (such as the leg or back) 
possibly referable to the foot.