How to Manage Foot Pain Caused by Flat Feet

If you've been told you have flat feet — or noticed that your arches seem to disappear entirely when you stand — you're not alone. Flat feet affect roughly 18 million adults in the United States, and while many people live with them without discomfort, others experience pain that can reach far beyond the foot itself. Understanding what flat feet are, why they hurt, and what you can do about it is the first step toward lasting relief.

What Are Flat Feet?

Flat feet, known medically as pes planus, occur when the arch of the foot collapses or never fully develops — causing the entire sole to make contact with the ground when you stand. There are two primary types:

Flexible flat feet — the most common type. The arch is visible when the foot is elevated but flattens completely under body weight. This is often painless, particularly in children, and may require no treatment unless symptoms develop.
Rigid flat feet — the arch is absent whether the foot is loaded or not. This type tends to be more symptomatic and may be associated with bone or joint abnormalities.

Most flat feet seen in adult podiatric patients are flexible, but the underlying cause matters when planning treatment.

How Flat Feet Cause Pain: The Kinetic Chain

Your feet are the foundation of your musculoskeletal system. When that foundation is unstable, the effects don't stay local. Flat feet change the mechanics of every step — altering the way force travels through the ankle, knee, hip, and lower back. This domino effect is called the kinetic chain, and it explains why flat feet can produce pain in places that seem completely unrelated to your arch.

Foot and arch pain — aching along the inner midfoot, especially after prolonged standing or walking
Heel pain — overpronation (inward rolling) associated with flat feet strains the plantar fascia; see our heel pain treatment page for more
Ankle pain and instability — the ankle joint is forced into abnormal alignment with every step; learn more on our ankle pain services page
Knee pain — inward rotation of the lower leg stresses the medial knee compartment
Hip and lower back pain — pelvic tilt compensation can cause chronic muscle fatigue and pain higher up the chain

Common Causes of Flat Feet

Flat feet can be present from birth or develop over time. Common causes and contributing factors include:

Genetics — arch structure runs in families; if a parent has flat feet, children are more likely to as well
Posterior tibial tendon dysfunction (PTTD) — the most common cause of adult-acquired flat foot. The posterior tibial tendon, which supports the arch, becomes inflamed, stretched, or torn over time.
Obesity — excess body weight increases pressure on the arch and accelerates tendon stress
Pregnancy — hormonal changes that loosen ligaments, combined with weight gain, can flatten the arch temporarily or permanently
Aging — tendons and ligaments lose elasticity over decades, allowing the arch to gradually collapse
Prior injury — ankle fractures or tendon tears that weren't fully rehabilitated

Symptoms to Watch For

Not every person with flat feet experiences pain, but the following symptoms suggest your flat feet may be affecting your function and warrant evaluation:

Aching or fatigue in the foot and arch after walking or standing
Swelling along the inner ankle or midfoot
Shoes that wear out unevenly on the inner edge of the sole
Difficulty standing on tiptoe on one foot
Knee, hip, or low back pain that correlates with time on your feet

Conservative Treatment Options

The vast majority of patients with painful flat feet improve significantly with non-surgical management. A structured conservative approach typically includes:

Stretching and physical therapy — targeted stretches for the Achilles tendon, calf muscles, and posterior tibial tendon reduce strain on the arch. Strengthening the intrinsic foot muscles improves arch support over time.
Supportive footwear — motion-control or stability shoes with a firm medial post help control overpronation. Avoid flat, unsupportive shoes like flip-flops or minimalist sneakers.
Custom orthotic insoles — prescription orthotics are precisely molded to your foot and provide arch support that off-the-shelf insoles can't match. They redistribute pressure, correct alignment, and reduce stress on the posterior tibial tendon. Learn more on our orthotics and footwear education page.
Anti-inflammatory measures — NSAIDs, icing, and activity modification during flare-ups
Weight management — reducing load on the arch is one of the most effective long-term strategies

When Is Surgery Needed?

Surgery is reserved for cases where conservative treatment has failed over six or more months, or when structural deformity is severe enough that non-surgical options are unlikely to provide lasting relief. Surgical procedures for flat feet may include:

PTTD repair or reconstruction — tendon transfer procedures to restore the posterior tibial tendon's function when it is damaged beyond conservative recovery
Osteotomy — repositioning of heel or midfoot bones to restore the arch and correct alignment
Fusion — in severe rigid flat foot deformity, joint fusion can provide pain relief and stability

The appropriate procedure depends on the type and severity of your flat foot, your age, and your activity goals. Your podiatrist will guide you through options if surgery becomes relevant.

Flat feet are common across Montana, and many of our patients in Butte, Bozeman, Anaconda, and Ennis have found lasting relief through a combination of orthotics and a structured stretching program. If foot, ankle, or knee pain is affecting your daily life, a podiatric evaluation is the right place to start.