Accessory Navicular Bone

Causes of an accessory navicular bone 

The condition is caused by the presence of an extra bone that some people are born with. Pain or symptoms typically happen when the accessory bone is aggravated by trauma, overuse, irritation from footwear or tension from a tendon in your foot. 

Risk factors for an accessory navicular bone 

Because the extra bone is present at birth, there aren’t traditional risk factors for it. You either have it or you don’t. Pain for an accessory navicular bone’s risk factors include:  

• Being born with the accessory bone (a congenital condition) 
• Adolescents undergoing growth spurts 
• Flat feet or fallen arches 
• Participation in high-impact or repetitive sports 
• Wearing tight or ill-fitting shoes that put pressure on the inner arch 

Symptoms of an accessory navicular bone 

These can include, but aren’t limited to: 

• Pain and swelling on the inner side of the foot or arch 
• Redness or tenderness over the bony bump 
• Pain that worsens with activity or certain footwear 
• Difficulty with walking, running or wearing shoes comfortably 
• A visible bony bump above the arch of your foot 

Diagnosing an accessory navicular bone 

Your doctor will perform a physical exam and assess the painful area. X-rays can confirm the presence of the accessory bone. In some cases, an MRI or bone scans may be used to evaluate inflammation or rule out other causes of foot pain. 

Treatment for an accessory navicular bone 

Non-surgical treatments include rest, ice, anti-inflammatory medications, orthotics and immobilization with a walking boot or cast. Physical therapy may help strengthen the foot and reduce stress on the area.  

In persistent or severe cases, surgery may be performed to remove the accessory bone and reattach the tendon.