Fallen Arches (Posterior Tibial Tendon Dysfunction): Symptoms, Causes & PT Treatment
Updated July 20261 minute read
Posterior tibial tendon dysfunction (PTTD) is weakening of the tendon on the inner ankle that supports your arch. As it struggles, the arch can flatten ("fallen arches"), causing inner-ankle and arch pain, especially with standing and walking. Catching it early matters — physical therapy with strengthening and supportive footwear or orthotics can keep it from progressing. Advanced cases may need more involved treatment.
What is PTTD?
The posterior tibial tendon runs along the inner ankle and helps hold up the arch. When it's overloaded and weakens, the arch gradually flattens — a leading cause of adult-acquired flatfoot.
Symptoms
Common features are pain and swelling along the inner ankle and arch, a flattening arch, fatigue with standing or walking, and difficulty rising onto the toes on one leg.
What causes it / risk factors
Age, higher body weight, overuse, and prior injury contribute. It's more common in middle-aged and older adults.
How it's diagnosed
A clinician examines the tendon and arch and checks single-leg heel raises. Imaging is used to stage more advanced cases.
Physical therapy treatment
What a PT does. Your therapist offloads the tendon, strengthens it and the surrounding muscles, and adds supportive footwear or orthotics as needed. Exercises & progression (overview). Progressive posterior tibialis and foot strengthening, plus orthotic support to protect the arch. Early treatment can slow or stop progression. Recovery timeline. Often months; early-stage cases respond best.
Treatment options compared
PT plus orthotic support is first-line for early stages. Bracing helps some. Surgery is considered for advanced, rigid deformity unresponsive to conservative care.
Red flags
Seek care for a hot, swollen, feverish foot, sudden inability to bear weight, or rapidly progressing deformity.
Frequently asked questions
Sources (2)
- Kulig K, et al. Nonsurgical management of posterior tibial tendon dysfunction with orthoses and resistive exercise: a randomized controlled trial. Phys Ther. 2009. — PubMed
- AAOS OrthoInfo: Progressive Collapsing Foot Deformity (Flatfoot), also known as posterior tibial tendon dysfunction (PTTD). — AAOS OrthoInfo
This article is for education only and isn't medical advice. Always talk to a licensed clinician about your specific situation.