Flat Feet and Fallen Arches: Causes, Symptoms, and What Helps

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Your arches look lower than they used to. Your feet feel tired by the end of the day. Maybe the inside of your ankle aches after a long walk, or your shoes wear down unevenly.

If that sounds familiar, flat feet or fallen arches may be part of the picture.

But here’s the part many articles miss: a low arch is not automatically a problem. Plenty of people have flat feet and never need treatment. The bigger question is whether your feet are comfortable, stable, and handling daily life well — or whether the arch seems to be changing, the foot is working harder than it should, and symptoms are starting to build. [1][2]

What are flat feet and fallen arches?

Flat feet means the arch on the inside of the foot is very low or absent when you stand. The medical term is pes planus. The NHS describes flat feet as a common condition where the feet press flat on the ground, while Cleveland Clinic notes that the soles of the feet may touch the floor when standing. [1][2]

Fallen arches is a related term, but it often suggests something more specific: an arch that has dropped or collapsed over time, especially in adulthood. That distinction matters. A foot that has always been flat and comfortable is different from a foot that is gradually changing shape and becoming painful. AAOS describes this acquired form as progressive collapsing foot deformity (PCFD), formerly called adult-acquired flatfoot. [2][3]

The arch is not just there for appearance. It helps absorb load, adapt to uneven ground, and support the foot during walking. But arch height alone does not tell you whether a foot is healthy or unhealthy. A flatter foot can function perfectly well. The real issue is whether it is painful, unstable, or changing. [2][4]

Are flat feet always a problem?

No. This is the most important point on the page, because many readers assume flat feet automatically need correction. They do not.

The NHS says flat feet are common and usually nothing to worry about. Chelsea and Westminster Hospital NHS Foundation Trust similarly notes that a flat or low-arched foot is not considered abnormal, and that arch height alone does not determine how well the foot functions. [1][4]

A person can have low arches and still:

• walk normally
• exercise comfortably
• have no pain
• need no treatment at all [1][2]

Flat feet become more important when you also notice things like:

• pain after walking or standing
• swelling near the inner ankle
• the foot rolling inward excessively
• a visible change in foot shape
• symptoms that are getting worse instead of staying stable [1][2][3]

So the better question is not, “Are my arches low?” It is, “Are my feet working well?”

Common symptoms of flat feet and fallen arches

Some people never notice any symptoms. Others feel discomfort gradually, especially with longer walks, more standing, or higher activity levels.

Common symptoms can include:

• aching in the arch or along the inner foot
• pain or swelling near the inside of the ankle
• foot fatigue that builds through the day
• shoes wearing unevenly
• the foot appearing to roll inward while walking
• discomfort with longer periods of standing or exercise
• pain that improves with rest but returns with activity [1][2][3]

In more advanced acquired cases, AAOS notes that pain can also develop on the outside of the ankle as foot alignment changes and nearby structures take on more stress. [3]

These symptoms do not automatically confirm that flat feet are the cause. But they are useful clues that foot mechanics may need a closer look.

Lifelong flat feet vs. arches that collapse over time

This is one of the most useful distinctions in the entire topic.

Some people have lifelong flat feet. Their arches never developed very prominently, or their feet have simply always been built that way. Oxford University Hospitals notes that most young children have flat feet as part of normal development, and while most outgrow it, some continue to have flatter feet without pain or limitations. [5]

Others develop fallen arches later in life. This is the pattern that often deserves more attention, because the arch is not just low — it is changing. AAOS explains that progressive collapsing foot deformity involves flattening of the arch along with other alignment changes, and it is commonly linked to dysfunction of the posterior tibial tendon. [3]

That difference matters because:

• a stable, lifelong flat foot is often harmless
• a foot that is flattening, painful, or becoming weaker may need treatment sooner [1][2][3]

What causes fallen arches in adults?

There is no single cause. In many adults, fallen arches happen because the structures that support the foot stop handling load as well as they used to.

One of the most important causes is posterior tibial tendon dysfunction. AAOS explains that the posterior tibial tendon helps support the arch and stabilize the foot during walking. When it becomes inflamed, overstretched, or torn, the arch can begin to collapse. [3]

Other contributing factors may include:

• prior foot or ankle injury
• age-related wear and tear
• obesity
• diabetes
• high blood pressure
• inflammatory arthritis
• ligament weakness or laxity
• repeated strain from prolonged standing or higher-impact activity [2][3]

Rheumatoid arthritis can also play a role. AAOS notes that progression of rheumatoid arthritis in the foot and ankle can shift alignment and contribute to flatfoot deformity over time. [6]

The key takeaway: “fallen arches” is not a single diagnosis. It is usually the result of an underlying structural, tendon, or joint issue that needs to be understood in context. [2][3][6]

Flat feet vs. overpronation

These terms are related, but they are not the same.

Flat feet describes structure.
Overpronation describes movement.

Cleveland Clinic defines overpronation as a gait pattern in which the foot rolls inward more than it should during walking or running. People with flat feet may be more likely to overpronate, but the two are not interchangeable. [2][7]

That matters because treatment is not always about trying to “rebuild” the arch visually. Often, the more practical goal is to:

• reduce excess motion
• improve comfort
• manage load better
• make walking and standing feel easier [2][4][7]

Can flat feet contribute to heel, ankle, or leg pain?

Yes — but the relationship is not always simple.

When the arch is low or collapsing, the foot may absorb and transfer force differently. Cleveland Clinic notes that flat feet can contribute to foot pain, ankle pain, and shin splints, especially when the foot rolls inward too much. [2]

Heel pain is one of the most common related complaints. AAOS notes that flat feet are one of the factors clinicians consider when evaluating plantar fasciitis, because the plantar fascia helps support the arch. [8]

Inner ankle pain can also be a clue, especially when the posterior tibial tendon is overloaded. And in more advanced cases, pain may shift to the outer ankle as alignment changes. [3][8]

What this does not mean is that flat feet automatically explain every case of knee, hip, or back pain. They can be one factor in a larger movement pattern, but symptoms farther up the chain usually need a broader assessment. That is an inference based on how these sources describe altered foot mechanics and overload patterns. [2][7]

What helps when flat feet or fallen arches hurt?

If flat feet are painless, you may not need to do anything. The NHS and Cleveland Clinic both note that flat feet without symptoms often do not require treatment. [1][2]

When symptoms do show up, conservative care is usually the first step.

Supportive footwear

This is often the simplest place to start. The NHS suggests wide, comfortable shoes with a low heel and a soft insole if flat feet are causing pain. [1]

Orthotics and arch supports

Orthotic inserts can help support foot position, reduce strain, and improve comfort. Cleveland Clinic notes that orthotics can be used to support flat feet, and AAOS discusses orthotics in the management of progressive collapsing foot deformity and plantar fasciitis. [3][9]

These supports usually help with symptom management and load distribution, not by permanently changing foot structure. [3][9]

Exercises and physical therapy

Strengthening and stretching can help when weakness, tightness, or tendon overload are part of the problem. AAOS’s foot and ankle conditioning guidance includes exercises for the calf, posterior tibialis, peroneal muscles, and plantar fascia. [10]

Physical therapy can be especially helpful if:

• the arch seems to be changing
• pain is persistent
• you are not sure whether the issue is strength, tendon overload, gait, or footwear [3][10]

Activity and lifestyle changes

In some cases, reducing prolonged standing, modifying activity during flares, or addressing excess load on the foot can make a meaningful difference. AAOS identifies obesity and repetitive strain as risk factors in adult-acquired flatfoot. [3]

Medical or surgical treatment

This is not the first step for most readers, but severe or rigid deformity may require specialist care. Cleveland Clinic and AAOS both note that some advanced cases need more than conservative management. [2][3]

When to see a podiatrist or doctor

A low arch by itself is usually not urgent. But it is worth getting evaluated if you notice:

• new or worsening pain
• swelling on the inside of the ankle
• one foot becoming flatter than the other
• a visible change in foot shape
• difficulty standing on tiptoe on one foot
• pain on the outside of the ankle
• symptoms that are not improving with better shoes and basic self-care [1][2][3]

AAOS emphasizes that progressive collapsing foot deformity can worsen if ignored, so a changing arch with inner ankle pain deserves more attention than a lifelong flat foot that has never caused trouble. [3]

Flat feet and fallen arches are common, and many people will never need treatment. A low arch is not automatically a problem. [1][2][4]

What matters is whether the foot is:

• painful
• changing over time
• tiring unusually fast
• affecting the way you walk and stand [1][2][3]

If your feet feel stable and comfortable, you may not need to do much at all. If they are hurting, collapsing, or limiting activity, supportive shoes, orthotics, targeted exercises, and the right evaluation can help you figure out what is actually going on and what to do next. [1][2][3][9][10]

Frequently Asked Questions

References

• [1] NHS. Flat feet. https://www.nhs.uk/conditions/flat-feet/
• [2] Cleveland Clinic. Flat Feet (Pes Planus): Types, Symptoms & Treatment. https://my.clevelandclinic.org/health/diseases/flat-feet-pes-planus
• [3] American Academy of Orthopaedic Surgeons (AAOS). Progressive Collapsing Foot Deformity (Flatfoot). https://orthoinfo.aaos.org/en/diseases–conditions/posterior-tibial-tendon-dysfunction/
• [4] Chelsea and Westminster Hospital NHS Foundation Trust. Treating the Flat Foot. https://www.chelwest.nhs.uk/your-visit/patient-leaflets/surgery-services/treating-the-flat-foot
• [5] Oxford University Hospitals. Flat Foot. https://www.ouh.nhs.uk/paediatricorthopaedics/information/conditions/flat-foot/
• [6] AAOS. Rheumatoid Arthritis of the Foot and Ankle. https://orthoinfo.aaos.org/en/diseases–conditions/rheumatoid-arthritis-of-the-foot-and-ankle
• [7] Cleveland Clinic. Overpronation: What It Is, Causes & Treatment. https://my.clevelandclinic.org/health/diseases/22474-overpronation
• [8] AAOS. Plantar Fasciitis and Bone Spurs. https://orthoinfo.aaos.org/en/diseases–conditions/plantar-fasciitis-and-bone-spurs
• [9] Cleveland Clinic. Orthotics: Definition, Risks, Benefits, Types & Tips. https://my.clevelandclinic.org/health/treatments/orthotics
• [10] AAOS. Foot and Ankle Conditioning Program. https://orthoinfo.aaos.org/en/recovery/foot-and-ankle-conditioning-program/