A fibrous knot (nodule) on the inside arch of the foot embedded within the plantar fascia — the band of tissue from the heel to the bottom of your toes — is a relatively rare condition called plantar fibromatosis (Ledderhose disease). The plantar fascia is a band of connective tissue that extends from the heel to the toes on the bottom of the foot. A plantar fibroma can develop in one or both feet and is a benign growth.
A plantar fibroma is a benign (non-cancerous) condition that can develop in one or both feet. The nodule usually does not go away without treatment.
The exact cause of plantar fibromatosis is not known, but some experts think there’s a connection between trauma and plantar fibromas. An injury to the fascia may cause tears in the tissue promoting the growth of nodules.
Causes & Risk Factors
Possible causes of plantar fibromatosis may include:
- Trauma to the plantar fascia
- Repetitive impact from activities such as running
- From injury to the bottom of the foot
- Genetics
- More common in people of northern European descent
- Rare in people of Asian descent
- Use of certain medications/supplements
- Beta-blockers
- Anti-seizure medications such as phenytoin
- Glucosamine/chondroitin
- Large doses of vitamin C supplements
- Long-term alcohol abuse
Plantar fibromatosis also frequently occurs in patients who have other fibroproliferative disorders such as:
- Dupuytren disease (also known as palmar fibromatosis)
- Keloids
- Peyronie’s disease
There is a higher rate of plantar fibromatosis in patients with certain conditions such as diabetes, chronic liver disease, and seizure disorders, but the potential connection is not understood.
What Does a Knot on the Foot Look and Feel Like?
Symptoms of plantar fibromatosis include a noticeable knot on the inside arch of the foot.
Characteristics of a knot on the inside of the foot vary depending on the size and location of the cyst and may include:
- Firm lump in the arch of the foot
- Mass may stay the same size or get larger over time
- Additional fibromas may develop
- May or may not cause pain
- When pain occurs, it is usually from shoes pushing against the mass, or when walking or standing barefoot
How Do You Get Rid of a Plantar Fibroma?
A knot on the inside of the foot due to plantar fascial fibromatosis usually does not go away on its own or get smaller without treatment.
Nonsurgical treatments for plantar fascial fibromatosis can help relieve pain but will not get rid of the mass and may include:
- Corticosteroid injections to help shrink the nodule and relieve pain
- Relief may only be temporary
- Fibroma may gradually return to its original size
- Topical medications such as verapamil 15% transdermal gel may reduce the size of a plantar fibroma if applied regularly for several months
- Nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (Advil, Motrin) or naproxen (Aleve) may help with pain and swelling
- Orthotic devices (shoe inserts) may help relieve pain by distributing the patient’s weight away from the fibroma
- Physical therapy methods can deliver anti-inflammatory medication into the fibroma without an injection
If the plantar fibroma causes significant pain or increases in size then surgery to remove the fibroma may be recommended.
Health Solutions From Our Sponsors
From 
Pain Resources
Featured Centers
Health Solutions From Our Sponsors
Image source: iStock Images
https://emedicine.medscape.com/article/1061903-overview
https://www.foothealthfacts.org/conditions/plantar-fibroma
https://www.pdlabs.net/plantar_fibromatosis/causes_plantar.html
https://www.footankleinstitute.com/conditions/cysts/plantar-fibroma