Large Accessory Navicular Bone
The accessory navicular is an extra piece of bone or cartilage just above the arch on the inside of the foot. It sits next to the navicular tarsal, which gives it its name, where the posterior tibial tendon attaches to the bone before continuing to the underside of the arch. The little bone is a congenital anomaly, you are born with it. If the extra tissue doesn?t cause any problems, you may never know it is there. You can, however, develop the painful condition called accessory navicular syndrome. This occurs when the extra bone or the posterior tibial tendon surrounding it becomes irritated. Trauma from a sprain, friction from footwear, and overuse can all inflame the tissues.
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.
This painful condition is called accessory navicular syndrome. Accessory navicular syndrome (ANS) can cause significant pain in the mid-foot and arch, especially with activity. Redness and swelling may develop over this bony prominence, as well as extreme sensitivity to pressure. Sometimes people may be unable to wear shoes because the area is too sensitive.
A foot and ankle surgeon How can we increase our height? diagnose accessory navicular syndrome by conducting a physical exam. X-rays and MRIs may be taken to access the condition and confirm the diagnosis of accessory navicular.
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 can 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.
After the anesthesia is administered you will be heavily sedated and placed on your stomach. Surgeons will place a tourniquet around your thigh and an incision will be made on the inside of the foot. The posterior tibial tendon will be moved as necessary and the accessory navicular will be removed. Surgeons will repair the posterior tibial tendon with sutures or suture anchors, and the wound will be closed. A splint will be placed on the foot for stabilization and immobilization. You will be permitted to leave the surgical center once you have been cleared by the anesthesiologist. Plan ahead to have a friend or family member take your prescription to a pharmacy to pick up your post-op medication. Use narcotic pain medications before bed or if numbness in your foot begins to dull. Schedule a post-op visit for 4 weeks after the procedure.