Flat feet, also known as fallen arches, is a common condition where the arches of the feet are low or nonexistent, causing the entire sole to touch the ground when standing. While flat feet can be painless for some, others may experience foot pain, fatigue, or problems with walking and alignment.

Understanding the causes of flat feet is essential to help manage the condition, prevent complications, and choose the right treatment. In this blog, we explore the various reasons flat feet develop, how they impact your health, and what you can do about them.

1. Genetics: Inherited Flat Feet

One of the most common causes of flat feet is genetics. Many people are born with flat feet, a condition known as congenital flatfoot. In these cases, the arches simply do not form during childhood development.

Children are usually born with flat feet because their foot arches are not yet developed. As they grow, the arch usually forms by around age 6. However, in some individuals, the arch never fully develops, leading to lifelong flat feet. If one or both parents have flat feet, there’s a higher likelihood their children will have them too.

2. Posterior Tibial Tendon Dysfunction (PTTD)

In adults, one of the most common causes of acquired flat feet is posterior tibial tendon dysfunction. The posterior tibial tendon is a key structure that supports the arch of your foot. If it becomes inflamed, overstretched, or torn, the arch can collapse over time.

PTTD often affects middle-aged adults and can be caused by overuse, trauma, or degenerative changes in the tendon. As the tendon weakens, it fails to support the foot, leading to a flat, often painful, foot.

3. Foot or Ankle Injuries

Injuries to the foot or ankle—such as fractures, dislocations, or severe sprains—can also lead to flat feet. Damage to the tendons, ligaments, or bones that support the arch can cause the foot structure to collapse.

Even if an injury heals, lingering weakness or misalignment may persist, contributing to flatfoot over time. It’s important to rehab injuries properly and wear supportive footwear during recovery to prevent long-term problems.

4. Arthritis and Inflammatory Conditions

Certain types of arthritis, such as rheumatoid arthritis or osteoarthritis, can damage the joints in your feet. This damage can weaken the structures that maintain the foot’s arch, causing it to flatten.

Inflammation in the joints, especially in the midfoot or hindfoot, can lead to pain, stiffness, and a progressive loss of the arch. Individuals with chronic joint conditions should monitor their foot health closely and seek professional care when needed.

5. Obesity and Excess Weight

Carrying excess weight places more pressure on the feet, especially the arches. Over time, this extra stress can strain the ligaments and tendons that support the foot, leading to arch collapse and flat feet.

Obesity also increases the risk of developing other flatfoot causes, such as tendon dysfunction and arthritis. Losing even a small amount of weight can significantly reduce pressure on the feet and improve overall foot function.

6. Pregnancy

During pregnancy, women may experience temporary flat feet due to two key factors:

  • Weight gain: Increased body weight puts more pressure on the feet.

  • Hormonal changes: Pregnancy hormones like relaxin loosen ligaments throughout the body, including those in the feet.

This combination can lead to the flattening of the arch during pregnancy. In many cases, the arch returns to normal postpartum, but for some women, the change can be permanent.

7. Aging and Wear and Tear

As we age, the tendons and ligaments in our feet naturally weaken. Over time, these changes can lead to a gradual collapse of the foot arch.

Adult-acquired flatfoot is most common in individuals over the age of 40, particularly women. Without proper care, the condition can progress and affect walking, posture, and alignment throughout the body.

8. Improper or Unsupportive Footwear

Wearing shoes that lack proper arch support—like flip-flops, high heels, or worn-out sneakers—can contribute to the development or worsening of flat feet.

Unsupportive shoes may not directly cause flat feet but can strain the foot’s ligaments and tendons, especially if worn for long periods. Over time, this can contribute to arch collapse, particularly in those already at risk.

9. Tarsal Coalition (Bone Fusion)

Tarsal coalition is a rare congenital condition where two or more of the tarsal bones in the foot fuse together. This restricts motion and flexibility in the foot, which can result in a rigid flat foot.

Tarsal coalition usually appears in adolescence and can cause foot pain and stiffness. Treatment may include physical therapy, orthotics, or surgery in severe cases.

10. Neuromuscular and Developmental Conditions

Certain neurological or muscular conditions affect how the foot muscles function and develop, leading to flat feet. These may include:

  • Cerebral palsy

  • Muscular dystrophy

  • Spina bifida

  • Charcot-Marie-Tooth disease

In these cases, flat feet are often part of a broader set of musculoskeletal issues and may require specialized care.

When to See a Specialist

While many people with flat feet experience no symptoms, others may deal with discomfort, fatigue, or alignment issues in the ankles, knees, hips, or lower back.

Consult a professional if you experience:

  • Persistent foot or ankle pain

  • Difficulty walking or standing for long periods

  • Swelling around the arch or ankle

  • A sudden collapse of the arch

  • Uneven wear on your shoes

A chiropractor, or orthotic specialist can help determine the cause of your flat feet and recommend treatment options like custom foot orthotics, supportive footwear, or strengthening exercises.

Flat feet can result from a variety of causes—ranging from genetics and tendon dysfunction to obesity, injury, or aging. While not always problematic, untreated flat feet can lead to pain, fatigue, and even postural problems that affect the knees, hips, and spine.

Understanding what causes flat feet is the first step toward effective treatment and prevention. Whether you’ve had flat feet since childhood or developed them later in life, there are solutions to help support your foot health and improve your quality of life.

If you’re concerned about flat feet or foot pain, don’t ignore it. Early intervention with custom orthotics, proper footwear, and professional guidance can make a lasting difference.

Need support for your flat feet? At Burrard Chiropractic and Foot Orthotics, we specialize in diagnosing and treating flat feet with custom orthotics and evidence-based care. Contact us today to book an assessment and take the first step toward healthy, pain-free feet.

Article by: Dr. Farokh Zavosh

Burrard Chiropractic and Foot Orthotics – Vancouver Chiropractor