Accessory Navicular

What is an Accessory Navicular?

An accessory navicular, sometimes referred to as os navicularum or tibiale externum is an extra piece of bone that is located at the inner side of the arch next to the navicular bone in the foot. An accessory navicular is congenital which means it is present at birth and may cause no pain at all until later in life. For some the pain may feel like a dull ache and for others it may present as extremely painful with swelling in the area. An accessory navicular is usually picked up on an X-ray and it is not uncommon to see an accessory bone in both feet.

What is Accessory Navicular Syndrome?

Accessory navicular syndrome is the term used to describe a painful accessory navicular bone or a painful tibialis posterior tendon caused by the accessory navicular. The tibialis posterior tendon is a muscle that originates at the back of the leg below the knee between your tibia and fibula and runs down the inside of your ankle and attaches to the navicular bone.

How does Accessory Navicular Syndrome occur?

  •  Trauma to the ankle or foot such as an ankle sprain
  •  Tight footwear causing irritation to the inside of the foot
  •  Too much activity or overuse

How can you treat Accessory Navicular Syndrome?

  •  Icing 
  •  Rest
  • Medications
  •  Casting or walking boot
  • Strengthening Exercises
  • Custom Foot Orthotics
  •  Surgery
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