There are many areas of the foot and ankle which can have accessory ossification, or extra bone. The most common of these is the accessory navicular bone. It occurs in 4-14% of the population. It usually appears during adolescence.

An accessory navicular is not part of the normal bone structure, but it is congenital. It can manifest as an extra bone or piece of cartilage located on the inner side of the foot above the arch. The posterior tibial tendon attaches in this area, and the accessory navicular is incorporated with the tendon.

Under normal circumstances, individuals who have an accessory navicular do not experience any problems unless the bone and posterior tibial tendon are irritated. This can happen if the foot or ankle is sprained or if ill-fitting footwear rubs against the bone. Aggravation of this area can also be caused by overuse or excessive activity. Flat feet also add more strain to the posterior tibial tendon. This irritation can produce inflammation of the accessory navicular.

Treatment for accessory navicular syndrome is directed toward relieving symptoms, and nonsurgical approaches are used first. These may include:

• Immobilization of the foot to allow the area to rest and reduce inflammation.
• Icing the area to decrease swelling.
• Nonsteroidal anti-inflammatory drugs such as ibuprofen.
• Physical therapy to exercise and strengthen muscles and decrease inflammation.
• Orthotic devices used in shoes to provide arch support and prevent future symptoms.

The goal in treatment is to alleviate the discomfort. If symptoms reappear, similar treatment is applied unless surgery is deemed necessary.

Surgical Treatment for Accessory Navicular Syndrome

When nonsurgical treatment for accessory navicular syndrome is not successful, a surgical approach may be necessary. When this is the case, the accessory bone is removed. Reshaping the area and repair of the posterior tibial tendon to improve its function is usually necessary.

The accessory navicular is an extra piece of bone or cartilage that has no effect on the function of your foot. It can, however, pose a problem for some individuals. If you are feeling pain or discomfort in your foot, contact the office of Dr. Stuart Mogul. After a thorough examination, he will recommend treatment to relieve your symptoms.