Accessory Ossicle Navicular Treatment
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
Most of the time, this condition is asymptomatic and people may live their whole lives unaware that they even have this extra bone. The main reason the accessory navicular bone becomes problematic is when pain occurs. There is no need for intervention if there is no pain. The accessory navicular bone is easily felt in the medial arch because it forms a bony prominence there. Pain may occur if the accessory bone is overly large causing this bump on the instep to rub against footwear.
Symptoms
It?s common for any symptoms to present during adolescence, when bones are maturing, though problems may not occur until adulthood. You may notice a bony prominence on the inner side of the midfoot. There may or may not be redness and swelling around this bump, especially if it rubs against footwear. You may be prone to blisters or sores in the area. Pain generally involves a vague ache or throbbing in the midfoot and arch as well, especially when you?re active. Many people with this syndrome develop flat feet, too, which can create additional strain in the foot.
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
Fortunately, surgery is not the only answer when it comes to relieving symptoms of accessory navicular syndrome. The physician may recommend wearing a cast or walking boot for a period of time so the foot can recover from the inflammation. Ice may be used to relieve swelling, too, although it should be wrapped to avoid direct contact with the skin.
Surgical Treatment
If non-surgical treatment fails to relieve the symptoms of accessory navicular syndrome, surgery may be appropriate. Surgery may involve removing the accessory bone, reshaping the area, and repairing the posterior tibial tendon to improve its function. This extra bone is not needed for normal foot function.