Accessory Navicular: Extra Bone In the Foot
Some people have an ‘accessory’ or extra bone or piece of cartilage on the inner side of the foot.
An accessory navicular is an inborn condition that affects only a minority of the population. It is not part of normal bone structure and therefore is not present in most people. It may be found when the foot is x-rayed for other reasons, or when irritation develops.
Patients may not be aware of it until a change in their activity, growth spurt or new footwear creates friction.
Most cases of accessory navicular syndrome are treated conservatively in our clinics in Dallas, DeSoto or Sunnyvale (Texas).
What is Accessory Navicular Syndrome?
The navicular bone is located on the top of the foot near the arch. People who have this extra bone can feel a bump or bony protuberance on the top of the foot above the arch. While the bone itself does not cause pain, accessory navicular syndrome can develop when the bone and/or nearby tendon is irritated.
The navicular bone is attached to muscles, ligaments and the posterior tibial tendon. Since ligaments and tendons have poor blood supply and don’t heal easily, any irritation to the surrounding structures can develop into a painful condition.
At our clinics in Dallas, DeSoto and Sunnyvale, we treat accessory navicular syndrome by addressing the symptoms.
How Do You Know if You have Accessory Navicular Syndrome?
The foot and ankle are prone to bony ‘accessories’ which usually have no accompanying symptoms. Accessory navicular syndrome is often diagnosed when an adolescent complains of pain in the foot. Girls are more susceptible than boys, and the condition is usually bilateral, occurring in both feet.
Navicular accessory syndrome may be diagnosed when a trauma (foot or ankle sprain) aggravates the bone or tibial tendon, or when there is chronic irritation from footwear or overuse.
At our clinics in Sunnyvale, DeSoto and Dallas, we check for the following signs:
- A bony prominence on the inner side of the foot
- Redness and swelling in the are
- Pain or throbbing, usually occurring during or after activity
Diagnosing Navicular Accessory Syndrome
To diagnose accessory navicular syndrome, our medical staff asks about the patient’s activities and symptoms. We examine the foot for irritation or swelling. We also evaluate the bone structure, muscle, joint motion, and the patient’s gait. X-rays can usually confirm the diagnosis. MRI or other imaging tests may be used to determine any irritation or damage to soft-tissue structures such as tendons or ligaments.
Because navicular accessory bone irritation can lead to bunions, heel spurs and plantar fasciitis, it’s important to seek treatment.
Treatment Can Take One of Several Approaches
Non-surgical treatment for accessory navicular syndrome is designed to relieve symptoms.
Physical therapy can be prescribed to help correct any gait irregularities and strengthen the supporting muscles. We may suggest the foot be encased in a boot to relieve inflammation and irritation.
We may also prescribe anti-inflammatory medications to relieve symptoms.
Surgery is an option in some cases.
Ultimately, the goal of treatment for navicular accessory syndrome is to return the foot to a comfortable condition and help the patient resume normal activities.