As many as 14% of 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.Causes
Like all painful conditions, ANS has a root cause. The cause could be the accessory navicular bone itself producing irritation from shoes or too much activity. Often, however, it is related to injury of one of the structures that attach to the navicular bone. Structures that attach to the navicular bone include abductor hallucis muscle, plantar calcaneonavicular ligament (spring ligament) parts of the deltoid ligament, posterior tibial tendon.Symptoms
Most people with an accessory navicular do not have symptoms because the bone is so small that it causes no harm, or only develop symptoms after a trauma such as a break or sprain. When symptoms are present they could be a visible bony prominence, pain and throbbing, inflammation and redness, and flat feet.Diagnosis
To diagnose accessory navicular syndrome, the foot and ankle surgeon will ask about symptoms and examine the foot, looking for skin irritation or swelling. The doctor may press on the bony prominence to assess the area for discomfort. Foot structure, muscle strength, joint motion, and the way the patient walks may also be evaluated. X-rays are usually ordered to confirm the diagnosis. If there is ongoing pain or inflammation, an MRI or other advanced imaging tests may be used to further evaluate the condition.Non Surgical Treatment
Although operative treatment, and removal of the accessory navicular is possible, this is not usually indicated at first. Conservative nonoperative treatment is best, the course depending on the severity of the symptoms. When the pain is very severe, which could indicate a fracture, a period of immobilization might be required. This is done by waring a fracture boot, or a cast, which How you can increase your height?
help the ossicle stay stable, aiding in healing. Immobilization usually lasts between 4 to 6 weeks. Afterwards, physical therapy exercise, or any appropriate home course, should be used to help strengthen the ankle and return the ankle and foot to full range of motion, and have no pain on movement. Sometimes crutches are used when weight bearing is too painful, but it is best to try to bear weight when possible.Surgical Treatment
Depending upon the severity the non operative or conservative treatment should be maintained for at least 4- 6 months before any surgical intervention. There are 2 surgeries that can be performed depending upon the condition and symptoms. First is simple surgical excision. In this generally the accessory navicular along with its prominence is removed. In this procedure, skin incision is made dorsally to the prominence of accessory navicular. Bone is removed to the point where the medial foot has no bony prominence over the navicular, between the head of the talus and first cuneiform. Symptoms are relieved in 90% of cases. Second is Kindler procedure. In this the ossicle and navicular prominence is excised as in simple excision but along with the posterior tibial tendon advancement. Posterior tibial tendon is split and advanced along the medial side of foot to provide support to longitudinal arch. After surgery 4 week short leg cast, well moulded into the arch with the foot plantigrade is applied. Partial weight bearing till the 8th week and later full weight bearing is allowed. When the cast is being removed can start building up the ROM to counter atrophy and other physical therapy treatment which include stretching and strengthening exercises.