Posterior Tibial Tendon Dysfunction
A common cause of adult flatfoot and inner ankle pain
Quick Facts
- Type: Foot and ankle tendon disorder
- Location: Inner ankle and arch
- Common result: Gradual flattening of the foot
- Early treatment: Rest, supports, and physical therapy
Overview
The posterior tibial tendon runs along the inside of the ankle and helps support the arch of the foot and hold it in position while walking. Posterior tibial tendon dysfunction (PTTD) occurs when this tendon becomes inflamed, weakened, or torn, so it can no longer support the arch properly.
PTTD is one of the most common causes of adult-acquired flatfoot. It usually develops gradually and tends to worsen over time if untreated, as the arch slowly collapses. Caught early, the condition often responds well to non-surgical treatment such as rest, supportive devices, and physical therapy.
Symptoms
Symptoms often begin on the inner side of the ankle and foot and progress gradually.
- Pain and swelling along the inside of the ankle and arch
- Pain that worsens with activity, such as walking or standing for long periods
- Gradual flattening of the arch, often in one foot first
- The foot and toes turning outward as the condition advances
- Difficulty standing on the toes of the affected foot
- Later, pain may shift to the outer side of the ankle as the foot shape changes
Without treatment, the flattening can become fixed and lead to arthritis in the foot and ankle.
Causes
PTTD usually results from gradual wear and overload of the tendon, sometimes with an acute injury.
- Overuse: Repeated stress from walking, running, or high-impact activities
- Degeneration: Age-related weakening of the tendon over time
- Injury: A fall, ankle sprain, or sudden strain can damage the tendon
- Excess load: Carrying extra body weight increases stress on the tendon
The tendon has a relatively limited blood supply in one area, which may make it more prone to gradual breakdown and slow healing.
Risk Factors
- Middle age and older, with women affected more often
- Obesity or carrying extra weight
- High blood pressure or diabetes
- Activities or jobs involving prolonged standing or walking
- Previous ankle injury or sprain
- Flat feet or low arches
Diagnosis
Diagnosis is based on examination of the foot's shape and function, sometimes with imaging.
- Physical examination: Checking for swelling and tenderness along the tendon, the shape of the arch, and the ability to stand on the toes.
- Single-leg heel raise test: Difficulty raising the heel on one leg suggests tendon weakness.
- Imaging: X-rays show the bone alignment and any arthritis, while MRI or ultrasound can assess tendon damage.
Treatment
Most people improve with non-surgical care, especially when treated early.
- Rest and activity changes: Reducing high-impact activity to calm inflammation.
- Orthotics and supports: Custom or over-the-counter arch supports, braces, or sometimes a walking boot to support the tendon and arch.
- Physical therapy: Exercises to strengthen the tendon and surrounding muscles and improve flexibility.
- Anti-inflammatory measures: Ice and, when appropriate, anti-inflammatory medication for pain.
- Supportive footwear: Shoes that stabilize the foot.
- Surgery: Considered for advanced cases or when non-surgical care fails, to repair the tendon and correct foot alignment.
Recovery can take weeks to months, and consistent rehabilitation is important to restore strength and prevent worsening.
Prevention
Some steps may reduce the risk of developing PTTD or slow its progression:
- Maintain a healthy weight to reduce load on the tendon
- Wear supportive, well-fitting footwear
- Use arch supports if you have flat feet or low arches
- Build up activity gradually and avoid sudden increases in training
- Stretch and strengthen the foot and calf muscles
- Address inner ankle pain early before the arch begins to collapse
When to See a Doctor
See a doctor if you have ongoing pain or swelling along the inside of your ankle or arch, notice your foot flattening or rolling inward, or have trouble standing on your toes. Early treatment can prevent the foot deformity from becoming fixed and harder to treat.
Seek prompt care if you cannot bear weight after an injury, the foot suddenly changes shape, or there is significant swelling and pain, as this may indicate a more serious tendon or ligament injury that needs timely evaluation.
Frequently Asked Questions
What does the posterior tibial tendon do?
It runs along the inside of the ankle and supports the arch of the foot, helping hold the foot stable while walking. When it weakens or tears, the arch can collapse, which is why the condition is a common cause of adult flatfoot.
Will my foot get worse without treatment?
It often does. PTTD tends to progress, with the arch flattening more over time and the foot turning outward. Eventually the deformity can become fixed and lead to arthritis, so early treatment is important.
Can it be treated without surgery?
Yes, especially when caught early. Most people improve with rest, arch supports or braces, supportive shoes, and physical therapy. Surgery is reserved for advanced cases or when non-surgical care does not help.
How long does recovery take?
Recovery varies but often takes several weeks to a few months with non-surgical treatment, and longer after surgery. Consistent rehabilitation and supportive footwear are key to regaining strength and preventing recurrence.
When should I see a doctor about inner ankle pain?
See a doctor for ongoing pain or swelling on the inside of the ankle or arch, a foot that is flattening, or difficulty standing on your toes. Seek prompt care if you cannot bear weight after an injury or the foot suddenly changes shape.
References
- American Academy of Orthopaedic Surgeons (OrthoInfo). Adult Acquired Flatfoot.
- American College of Foot and Ankle Surgeons. Posterior Tibial Tendon Dysfunction.
- MedlinePlus, U.S. National Library of Medicine. Foot, ankle, and lower leg problems.