Right Accessory Navicular Excision
Overview
This condition has been observed in multiple family members and has propensity to occur slightly more in females than males. For most individuals this condition is a non-issue and most people who have them never have a problem with them. Over the years when x-raying patients for other problems I will point out that they have an extra bone in their foot and the usual response from the patient is nothing more than a yawn.
Causes
It is commonly believed that the posterior tibial tendon loses its vector of pull to heighten the arch. As the posterior muscle contracts, the tendon is no longer pulling straight up on the navicular but must course around the prominence of bone and first pull medially before pulling upward. In addition, the enlarged bones may irritate and damage the insertional area of the posterior tibial tendon, making it less functional. Therefore, the presence of the accessory navicular bone does contribute to posterior tibial dysfunction.
Symptoms
The primary reason an accessory navicular becomes a problem is pain. There is no need to do anything with an accessory navicular that is not causing pain. The pain is usually at the instep area and can be pinpointed over the small bump in the instep. Walking can be painful when the problem is aggravated. As stated earlier, the condition is more common in girls. The problem commonly becomes symptomatic in the teenage years.
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
Patients with a painful accessory navicular may benefit with four to six physical therapy treatments. Your therapist may design a series of stretching exercises to try and ease tension on the posterior tibial tendon. A shoe insert, or orthotic, may be used to support the arch and protect the sore area. This approach may allow you to resume normal walking immediately, but you should probably cut back on more vigorous activities for several weeks to allow the inflammation and pain to subside. Treatments directed to the painful area help control pain and swelling. Examples include ultrasound, moist heat, and soft-tissue massage. Therapy sessions sometimes include iontophoresis, which uses a mild electrical current to push anti-inflammatory medicine to the sore area.
Surgical Treatment
The above non-surgical options should be enough to treat accessory navicular syndrome. If they fail, a surgery would be necessary to remove the extra bone that has been causing the problems. The most common procedure for this condition is known as the Kidner procedure where a small incision is made over the navicular bone. The accessory navicular is identified and dissected free from the posterior tibial tendon. The posterior tibial tendon is then reattached to the remaining navicular bone.