Flatfeet: Symptoms, Types, Causes and Treatment

Flatfeet, also known as pes planus, is a common condition affecting people of all ages. While many individuals with flatfeet experience no discomfort, others can have pain, fatigue, or even difficulty walking. Understanding flatfeet requires a look at its symptoms, the different types, what causes it, and the best available treatments. This article explores all these aspects, drawing on the latest research to provide clarity and reassurance for patients, parents, and anyone interested in foot health.

Symptoms of Flatfeet

Flatfeet can present with a range of symptoms—or none at all. Many people are surprised to learn that having flatfeet doesn't always mean having pain or mobility issues. However, for those who do experience symptoms, the effects can be very noticeable, impacting daily life and activity levels.

Symptom	Description	Who's Affected	Source(s)
Pain	Aching, throbbing, or cramping	Some children & adults	1, 9, 12
Fatigue	Generalized tiredness	Especially children	1, 9
Shoe Wear	Excessive or uneven wear	Children & adults	9
Activity Limitation	Avoidance of walking/running	Children & adults	1, 9, 12

Table 1: Key Symptoms

Pain and Discomfort

Not everyone with flatfeet experiences pain. However, when symptoms arise, they often include dull, aching pain or cramps in the feet, ankles, or lower legs. This discomfort may intensify after long periods of standing, walking, or physical activity. In some cases, pain is localized to the medial midfoot or the sinus tarsi (a canal in the hindfoot) 1, 9, 12.

Fatigue and Activity Limitation

Children with symptomatic flatfeet may tire quickly during play or sports, sometimes refusing to participate in activities that require prolonged walking or running. Adults may notice more general fatigue or heaviness in the feet and legs after standing or moving for extended periods 1, 9.

Changes in Shoe Wear

One of the more subtle signs of flatfeet can be excessive or uneven wear on the inside edge of shoes. This is due to the inward rolling of the foot, also known as overpronation, which is common in people with flatfeet 9.

Asymptomatic Flatfeet

It’s important to note that many children and adults with flatfeet never experience symptoms. Asymptomatic flexible flatfeet, especially in children, are often considered a normal variant and usually do not require treatment 1, 2, 10, 12. However, even asymptomatic cases can show changes in foot function during walking—such as altered foot kinematics and reduced flexibility—highlighting the importance of monitoring for any progression or onset of symptoms 1.

Types of Flatfeet

Flatfeet is not a one-size-fits-all condition. There are several forms, each with distinct features and implications for treatment. Identifying the type is key to determining the right approach and understanding potential risks.

Type	Characteristics	Flexibility	Source(s)
Flexible Flatfoot	Arch disappears with weight, returns non-weightbearing	Flexible	1, 2, 5, 9, 10, 12
Rigid Flatfoot	Arch absent regardless of position	Rigid	2, 10, 11, 12
Pediatric Flexible	Normal variant in children	Flexible	2, 10, 11, 12
Adult Acquired	Progressive, often due to tendon dysfunction	Increasingly rigid	7, 9

Table 2: Types of Flatfeet

Flexible Flatfoot

This is the most common type, particularly in children. The arch is present when the foot is not bearing weight but flattens upon standing. Most pediatric cases fall into this category and are typically painless and benign. However, a subset becomes symptomatic, presenting with pain or fatigue 1, 2, 9, 10, 12.

Rigid Flatfoot

Here, the arch is absent whether the individual is standing or sitting. Rigid flatfoot can indicate underlying pathology such as tarsal coalition (an abnormal connection between foot bones), congenital vertical talus, or neurologic conditions. This type is less common but more likely to cause pain and require intervention 2, 10, 11, 12.

Pediatric Flexible Flatfoot

In children, flexible flatfoot is usually a developmental stage. Most infants are born with flatfeet, and the arch develops during the first decade of life. It is considered normal unless associated with symptoms or loss of flexibility 2, 10, 11, 12.

Adult Acquired Flatfoot

This type typically develops in middle-aged or older adults, often due to degeneration of the posterior tibialis tendon, which supports the arch. The condition starts with flexibility but becomes increasingly rigid and disabling as the deformity progresses 7, 9. Secondary damage to ligaments and soft tissue can exacerbate the collapse of the arch and foot malalignment 7.

Causes of Flatfeet

The causes of flatfeet are diverse, ranging from genetic predisposition to acquired factors later in life. Understanding these causes helps guide prevention, monitoring, and treatment strategies.

Cause	Description	Typical Onset	Source(s)
Developmental	Normal arch development delay	Childhood	2, 10, 11, 12
Tendon Dysfunction	Degeneration of posterior tibialis	Adulthood	7
Structural Variants	Altered bone/joint morphology	Any age	8, 6
Tight Heelcord	Achilles tendon contracture	Childhood/adolescence	1, 11, 12
Pathologic Causes	Tarsal coalition, CVT, neuromuscular	Any age (often children/adolescents)	2, 10, 11, 12
Obesity	Increased body weight	Childhood/adulthood	3

Table 3: Causes of Flatfeet

Normal Developmental Variation

Most children are born with flatfeet. The arch typically develops by age 7–10. Many cases of pediatric flexible flatfoot represent a normal stage of growth, not a true deformity 2, 10, 11, 12. Only a small proportion develop lasting or symptomatic flatfeet.

Tendon Dysfunction

In adults, especially women over 40, the most common cause is degeneration of the posterior tibialis tendon. When this tendon weakens or tears, it can no longer support the arch, leading to progressive flattening and foot malalignment. This is known as adult acquired flatfoot deformity (AAFD) 7.

Structural and Morphological Factors

Variations in the shape and alignment of foot bones (such as the talus and navicular) can predispose individuals to flatfeet. Research has shown that people with flatfeet may have a talar head that is more proximally oriented and a deeper navicular cup, which together favor arch collapse and forefoot abduction 8.

Tight Heelcord (Achilles Contracture)

A tight Achilles tendon can contribute to flatfoot by limiting ankle movement and placing extra stress on the arch. This is often seen in children and adolescents and is a frequent cause of symptomatic flexible flatfoot 1, 11, 12.

Pathologic Causes

Some cases are due to underlying pathology, such as:

• Tarsal coalition: Abnormal fusion between foot bones, often presenting in adolescence 2, 10, 11, 12.
• Congenital vertical talus (CVT): A rare rigid flatfoot seen in infants 2, 10.
• Neuromuscular or connective tissue disorders: Such as cerebral palsy or Ehlers-Danlos syndrome 2.

Obesity

While previous studies have linked increased body mass to flatfeet in children, recent research using more anatomically accurate foot posture indices finds little to no association between BMI and the presence of flatfeet 3. This challenges the common assumption that heavier children are at higher risk for flatfoot.

Treatment of Flatfeet

Treatment for flatfeet is highly individualized, depending on the type, symptoms, and underlying cause. Many cases never require intervention, while others may benefit from conservative or, rarely, surgical approaches.

Treatment	Indication	Evidence/Notes	Source(s)
Reassurance	Asymptomatic, flexible flatfeet	Most cases in children	2, 10, 11, 12
Stretching	Tight Achilles/heelcord	Symptomatic relief	1, 11, 12
Orthotics	Symptomatic, flexible flatfeet	Limited evidence	2, 12
Supportive Shoes	Mild symptoms	Conservative measure	9, 12
Surgical Options	Rigid or persistent pain	Osteotomy, fusion, arthroereisis	2, 5, 7, 9, 12

Table 4: Treatment Approaches

Observation and Reassurance

For most children with flexible, painless flatfeet, reassurance and education are the only "treatments" needed. These cases are considered normal variants and do not negatively impact function or future foot health 2, 10, 11, 12.

Stretching and Physical Therapy

If symptoms are related to a tight Achilles tendon, stretching exercises can be very effective. A structured stretching program can relieve pain and improve mobility, especially in children and adolescents 1, 11, 12.

Orthotics and Supportive Footwear

For those experiencing discomfort, arch supports or custom orthotic devices are sometimes recommended. However, high-quality evidence for their benefit—particularly in changing foot shape or preventing long-term problems—is lacking 2, 12. Supportive footwear with good arch support may provide comfort but does not alter the underlying flatfoot 9, 12.

Surgical Intervention

Surgery is rarely needed. It is reserved for:

• Rigid flatfeet or those with underlying causes like tarsal coalition or CVT.
• Flexible flatfeet that remain painful and disabling despite prolonged nonsurgical management.

Surgical options include:

• Osteotomies: Cutting and realigning bones to restore the arch.
• Fusions: Permanently joining bones to stabilize the foot.
• Arthroereisis: Inserting an implant in the subtalar joint to limit excessive motion (more common in Europe) 2, 5, 7, 9, 12.

Patients with adult acquired flatfoot from tendon dysfunction may require more extensive reconstruction, including tendon transfers and ligament repairs 7. The decision for surgery is always individualized and based on the severity of symptoms, degree of deformity, and failure of conservative measures.

Conclusion

Flatfeet is a diverse and often benign condition, especially in childhood. Understanding the symptoms, types, causes, and treatments is essential for appropriate management and patient reassurance. Most cases require nothing more than observation, but for those with pain or functional limitation, there are effective options available.

Key takeaways:

• Most flatfeet, especially in children, are flexible and asymptomatic, requiring no treatment 2, 10, 11, 12.
• Symptoms, when present, include pain, fatigue, activity avoidance, and sometimes excessive shoe wear 1, 9, 12.
• Types include flexible flatfoot, rigid flatfoot, pediatric flexible flatfoot, and adult acquired flatfoot 1, 2, 7, 9, 10, 12.
• Causes range from normal development and tendon dysfunction to structural foot differences and rare pathologies 2, 7, 8, 10, 11, 12.
• Treatment is based on symptoms and underlying causes, with reassurance for most, stretching for tight heelcords, limited evidence for orthotics, and surgery reserved for rare, severe cases 1, 2, 9, 11, 12.

If you or your child have flatfeet, rest assured that in most cases, it is a harmless variation of normal development. If symptoms do arise, consult a healthcare provider for a tailored approach.