Left Accessory Navicular Excision

Overview
Sometimes, feet do weird things. For instance, about 10% of the general population?s feet have decided that having an extra bone in the mix is a really great idea. This extra bone (or sometimes a bit of cartilage), is called an accessory navicular. It shows up in a tendon called the posterior tibial tendon (which is a fancy name - but just remember, it helps support the arch of the foot) on the middle of the inside of the foot, just above the arch. This extra little bone is present from birth, so it?s not something that?ll suddenly grow later in life. Now, accessory navicular syndrome is when that extra bone starts causing issues with your shoe-wearing, or even the shape and function of your foot. It?s the syndrome you want to worry about, not necessarily the extra bone itself.



Causes
This can result from any of the following. Trauma, as in a foot or ankle sprain. Chronic irritation from shoes or other footwear rubbing against the extra bone. Excessive activity or overuse. Many people with accessory navicular syndrome also have flat feet (fallen arches). Having a flat foot puts more strain on the posterior tibial tendon, which can produce inflammation or irritation of the accessory navicular.

Symptoms
This painful condition is called accessory navicular syndrome. Accessory navicular syndrome (ANS) can cause significant pain in the mid-foot and arch, especially with activity. Redness and swelling may develop over this bony prominence, as well as extreme sensitivity to pressure. Sometimes people may be unable to wear shoes because the area is too sensitive.

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
A combination of the following non-surgical treatments may be used to relieve the symptoms of accessory navicular syndrome. Immobilizing the foot with a cast or a removable walking boot allows the foot to rest and reduces inflammation. Applying ice to the affected area is an effective way to reduce swelling and inflammation. Wrap a bag of ice with a thin towel and apply for intervals of 15 to 20 minutes. Never put ice directly on the skin. Oral nonsteroidal anti-inflammatory drugs (NSAIDs) including aspirin or ibuprofen might be prescribed. Sometimes, a combination of immobilization and oral or injected corticosteroid medications may reduce pain and inflammation. Physical therapy may be prescribed to include exercises and treatments that increase muscle strength, decrease inflammation and help prevent the recurrence of symptoms. Custom orthotic devices worn in the shoe provide arch support and may prevent future symptoms from developing. The symptoms of this syndrome may reappear even after successful treatment. If so, non-surgical treatments are often repeated.



Surgical Treatment
If all nonsurgical measures fail and the fragment continues to be painful, surgery may be recommended. The most common procedure used to treat the symptomatic accessory navicular is the Kidner procedure. A small incision is made in the instep of the foot over the accessory navicular. The accessory navicular is then detached from the posterior tibial tendon and removed from the foot. The posterior tibial tendon is reattached to the remaining normal navicular. Following the procedure, the skin incision is closed with stitches, and a bulky bandage and splint are applied to the foot and ankle. You may need to use crutches for several days after surgery. Your stitches will be removed in 10 to 14 days (unless they are the absorbable type, which will not need to be taken out). You should be safe to be released to full activity in about six weeks.