Understanding Adult-Acquired Flatfoot and Its Impact on Foot Pain

Flat feet, also known as fallen arches, can affect individuals from childhood through adulthood. While some people are born with flat feet, many adults develop this condition later in life, a form known as adult-acquired flatfoot deformity (AAFD). This condition can cause significant foot pain, discomfort, and mobility issues if left untreated.

Adult-acquired flatfoot occurs when the arch of the foot gradually collapses due to the weakening or dysfunction of the posterior tibial tendon, which plays a critical role in maintaining the arch. Over time, this dysfunction causes the arch to flatten, resulting in altered foot mechanics and increased strain on other structures.

At Diablo Foot & Ankle, located in Walnut Creek and Antioch, CA, our board-certified podiatrists specialize in diagnosing and treating adult flatfoot. Understanding the causes, symptoms, and treatment options is essential for those experiencing foot pain and wanting to regain comfortable mobility.

What Is Adult-Acquired Flatfoot?

Adult-acquired flatfoot is a progressive condition characterized by the collapse of the foot’s arch during adulthood. Unlike congenital flat feet, which are present from birth, AAFD develops over time and is often linked to injury, tendon dysfunction, or arthritis.

The key factor behind AAFD is the failure of the posterior tibial tendon (PTT). This tendon runs along the inside of the ankle and foot and provides support for the arch. When the PTT becomes inflamed, stretched, or torn, it can no longer maintain the arch’s height, causing the foot to flatten and collapse.

As the arch collapses, the foot becomes misaligned, which shifts weight distribution and places extra pressure on the foot and ankle joints. This abnormal positioning can cause pain on the inside of the foot and ankle, difficulty walking or standing for long periods, and, eventually, arthritis in the foot joints.

AAFD progresses through stages, starting with mild symptoms and gradually worsening if untreated. Early intervention is crucial to prevent severe deformity and long-term disability.

Symptoms and Signs of Adult Flatfoot

Recognizing the symptoms early can lead to more effective treatment. Common signs of adult-acquired flatfoot include:

• Pain and Swelling: Pain often develops along the inside of the ankle and foot, near the posterior tibial tendon. Swelling may accompany the discomfort.
• Flattened Arch: You may notice that your foot’s arch appears lower or completely collapsed, causing the sole to almost touch the ground.
• Heel Pain: The heel may start to tilt outward, causing pain on the outside of the foot and ankle.
• Difficulty Walking: As the foot structure changes, walking becomes less stable and more tiring. You may also experience limping.
• Foot Fatigue: The foot may tire quickly during activity.
• Changes in Foot Shape: The toes may start to point outward (“too many toes” sign), and the foot may widen.
• Stiffness and Reduced Mobility: As arthritis develops in the foot joints, stiffness and decreased range of motion can occur.

Causes and Risk Factors

Several factors contribute to adult-acquired flatfoot deformity, including:

• Posterior Tibial Tendon Dysfunction: The primary cause, resulting from tendon overuse, injury, or degeneration.
• Age: Tendon strength naturally diminishes with age, increasing the risk.
• Obesity: Excess weight increases stress on the tendons and foot structures.
• Trauma or Injury: Ankle sprains, fractures, or tendon injuries can trigger flatfoot development.
• Arthritis: Inflammatory conditions such as rheumatoid arthritis or osteoarthritis can damage foot joints.
• Diabetes: Peripheral neuropathy and poor circulation in diabetes can contribute to tendon and joint problems.
• High-Impact Sports or Occupations: Activities placing repetitive strain on the foot may accelerate tendon wear.
• Genetics: Some individuals may have a predisposition to flatfoot or weakened tendons.

Diagnosis and Evaluation

At Diablo Foot & Ankle, we use a comprehensive approach to diagnose AAFD:

• Physical Examination: Assessing foot shape, arch height, flexibility, and tenderness.
• Gait Analysis: Observing walking patterns to identify biomechanical changes.
• Imaging Tests: X-rays, MRI, or ultrasound to evaluate tendon integrity and joint health.

Early diagnosis allows for more conservative treatment options and better outcomes.

Treatment Options for Adult Flatfoot

Treatment depends on the severity of the condition and the patient’s symptoms:

Conservative Care

• Orthotics: Custom arch supports help realign the foot and relieve pressure.
• Physical Therapy: Targeted exercises strengthen the posterior tibial tendon and improve flexibility.
• Medications: Anti-inflammatory drugs reduce pain and swelling.
• Activity Modification: Reducing high-impact activities and using supportive footwear.

Regenerative Therapies

• PRP (Platelet-Rich Plasma) Injections: Utilizing your body’s healing factors to repair damaged tendons.
• AmnioFix Injections: Contains growth factors to promote tissue regeneration and reduce inflammation.

Surgical Intervention

In advanced cases with severe deformity or arthritis, surgery may be necessary to repair tendons, realign bones, or fuse joints for pain relief and restored function.

Why Choose Diablo Foot & Ankle?

Our team of board-certified podiatrists has extensive experience in diagnosing and managing adult-acquired flatfoot. We combine advanced diagnostic tools with innovative treatments to create personalized care plans focused on restoring function and relieving pain.

Schedule Your Consultation Today

If you experience persistent foot pain, arch collapse, or mobility issues, don’t wait to seek expert care.

📞 Call (925) 464-1982
📍 Walnut Creek, San Ramon, & Antioch
🌐 diablofootankle.com

Book an appointment with Diablo Foot & Ankle and discover how treatments like PRP or AmnioFix injections can help you regain foot health and mobility.