The accessory navicular is an additional bone fragment or bit of cartilage within the arch of the foot that may or might not result in symptoms. It is usually often known as an os navicularum or os tibiale externum. The bone is integrated inside the tendon of the posterior tibial muscle which attaches in the region. The extra bone is on the medial side of the navicular bone which is the bone that is at the top of the arch of the foot. It is present in anywhere from 5-15% of people. It’s not usually an issue, however the prominence of the bone can make pressure from the footwear painful. Sometimes the bone is at such a place which it may modify the angle of action of the posterior tibial muscle that might affect foot biomechanics and would bring about several alignment concerns, such as a flat foot.
The diagnosis is generally by a x-ray where the existence of the bone is clear. There are various varieties that the x-ray can help establish which one it is. The Geist grouping divides the accessory navicular bones in to three differing types. Each of the 3 kinds has an effect on the structure and function in the foot in a different way and each of the 3 differing types necessitates a unique treatment approach.
The aim of treatment solutions are to ease the signs and symptoms and prevent it getting painful. In the event the pain is extremely bad, then putting the foot in a plaster cast or replaceable walking boot will allow the affected region to rest which helps the pain. Ice may also be used to decrease swelling. Oral nonsteroidal anti-inflammatory drugs (NSAIDs) can be employed combined with immobilization to help decrease the swelling and pain. Physical exercises and treatments to strengthen the muscles could also be advised, in particular over the long term that can help avoid a recurrence of the symptoms. Foot orthotic inserts will be extremely useful to protect the region and become mainly helpful if the accessory navicular is causing a flat foot.
The accessory navicular bone can certainly be a unique concern is sports activities including skiing along with ice skating. For the reason that the boots in these sporting activities will go around the feet and its quite firm. Therefore, if someone has a enlarged piece of bone on the feet, such as an accessory navicular, this could be really painful and also tricky to treat. Things like doughnut shaped padding to remove the pressure from the footwear off the spot is frequently advantageous. This is also where the skills of a boot maker or a qualified ski boot fitter is vital. These experts are used to coping with these sorts of problems and can modify the boot around the accessory bone to make it more at ease. A podiatric physician can often help with all this.
If the traditional non-surgical treatments don’t alleviate the signs and symptoms, then surgical procedures could be indicated. Surgery can involve taking out the additional bone, re-shaping the region and reconstructing the tendon to better its biomechanics. This additional bone just isn’t needed for normal foot function, and so in theory it won’t be a problem.
For more on the classification of an accessory navicular:
https://themedicaldispatch.com/classification-of-an-accessory-navicular/
Article by: Craig Payne August 1, 2022