Will Accessory Navicular Syndrome Warrant Surgery

Overview
For most people with an accessory navicular, the extra bone does not cause any problems and most are unaware of its presence. But certain activities or circumstances may cause the extra bone or the tibialis posterior tendon that contains it to grow irritated. This is called accessory navicular syndrome, and its possible causes include sprains, overuse, or wearing shoes that constantly rub against the bone. Individuals who have a collapsed arch (commonly known as flat feet) may be at greater risk of accessory navicular syndrome, assuming they have the extra bone, because of the added daily trauma placed on the tibialis posterior tendon.



Causes
An injury to the fibrous tissue connecting the two bones can cause something similar to a fracture. The injury allows movement to occur between the navicular and the accessory bone and is thought to be the cause of pain. The fibrous tissue is prone to poor healing and may continue to cause pain. Because the posterior tibial tendon attaches to the accessory navicular, it constantly pulls on the bone, creating even more motion between the fragments with each step.

Symptoms
Adolescence is a common time for the symptoms to first appear. This is a time when bones are maturing and cartilage is developing into bone. Sometimes, however, the symptoms do not occur until adulthood. The signs and symptoms of accessory navicular syndrome include a visible bony prominence on the midfoot (the inner side of the foot, just above the arch) Redness and swelling of the bony prominence. Vague pain or throbbing in the midfoot and arch, usually occurring during or after periods of activity.

Diagnosis
To diagnose accessory navicular syndrome, medical staff ask about the patient?s activities and symptoms. They will examine the foot for irritation or swelling. Medical staff 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.

Non Surgical Treatment
The goal of non-surgical treatment for accessory navicular syndrome is to relieve the symptoms. The following may be used. Placing the foot in a cast or removable walking boot allows the affected area to rest and decreases the inflammation. To reduce swelling, a bag of ice covered with a thin towel is applied to the affected area. Do not put ice directly on the skin. Nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, may be prescribed. In some cases, oral or injected steroid medications may be used in combination with immobilization to reduce pain and inflammation. Physical therapy may be prescribed, including exercises and treatments to strengthen the muscles and decrease inflammation. The exercises may also help prevent recurrence of the symptoms. Custom orthotic devices that fit into the shoe provide support for the arch, and may play a role in preventing future symptoms. Even after successful treatment, the symptoms of accessory navicular syndrome sometimes reappear. When this happens, non-surgical approaches are usually repeated.



Surgical Treatment
Surgical treatment of the accessory navicular syndrome with simple excision has the advantages of less invasive to the posterior tibial tenden and the medial longitudinal arch of the foot, shorter time of immobilization of the foot and stay in hospital, small incision and good clinical results. This procedure is one of the best selective treatments for the accessory navicular syndrome, especially for the patients without flatfoot deformity and old sprain injury.