There are three different types of accessory navicular. This extra cartilage, which What is leg length discrepancy?
turned into bone, is found attached to the posterior tibial tendon, just medial (inside) the navicular bone. The accessory navicular can affect the insertion of the posterior tibial tendon. This tendon has a job of keeping your foot aligned and helping to maintain an arch. The accessory navicular can be associated with a normal foot posture and alignment, or sometime with a flat (pes planus) foot.
Let us see the reasons why the tendon or the bone would get aggravated. Ankle or foot sprain, irritation of the bone caused by footwear, overusing the foot, quite common in athletes and dancers. People born with this extra bone are also known develop flat feet which also adds to the strain on the posterior tibial tendon and lead to the syndrome.
Perhaps the most common of the extra bones in the foot, the accessory navicular bone is estimated to be present in 7 to 19 percent of the population. Zadek and Gold maintained that the bone persisted
as a distinct, separate bone
in 2 percent of the population. Also be aware that the accessory bone normally fuses completely or incompletely to the navicular. It is this incomplete fusion which allows for micromotion, which, in turn, may cause degenerative changes that can also contribute to the pain.
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
Treatment options for a painful accessory navicular can include anti-inflammatory medications, rest, arch support structures in the shoe, or use of a cast or splint. Severe cases may require surgery.
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.