What is an accessory navicular bone?

The accessory navicular is an additional bone fragment or bit of cartilage in the arch of the foot that may or might not cause issues. It is usually known as an os navicularum or os tibiale externum. It is incorporated within the tendon of the posterior tibial muscle which attaches in the area. The extra bone is on the inside side of the navicular bone which is the bone that is towards the top of the mid-foot (arch) of the feet. It happens in anywhere from 5-15% of people. It's not usually an issue, but the prominence of the accessory bone could make force from the shoes painful. Occasionally the accessory bone is in such a position which it will change the angle of action with the posterior tibial muscle which affect foot biomechanics and could result in several alignment concerns, for instance a flat foot.

The verification is commonly by x-ray in which the existence of the bone is pretty obvious. There are lots of types that the x-ray may help figure out which one it is. The Geist classification separates the accessory navicular bones into 3 different types. Each of the 3 varieties has effects on the structure and biomechanics with the foot in a different way and each of the three different kinds must have a different treatment process.

The goal of treatment methods are to relieve the symptoms preventing it getting painful. If the pain is quite bad, then putting the foot in a fibreglass cast or replaceable walking splint will permit the affected area to rest and help the symptoms. Ice may also be used to help reduce inflammation. Oral nonsteroidal anti-inflammatory drugs (NSAIDs) can be employed together with immobilization to help decrease the pain and inflammation. Exercise routines and therapies to strengthen the muscles could also be encouraged, in particular over the long term to help you reduce a recurrence of the signs and symptoms. Foot orthotic devices tend to be extremely beneficial to protect the area and become mainly useful if the accessory navicular is causing a flat foot.

The accessory navicular can be a particular concern is sports for example skiing and ice skating. It is because the footwear in these sports goes right around the feet and it is rather firm. Consequently, if someone has a enlarged bit of bone on the foot, just like an accessory navicular, this could be rather painful as well as difficult to manage. Things like donut shaped pads to deflect the pressure coming from the boot off the area is frequently advantageous. This can be where the knowledge of a boot maker or a qualified ski boot fitter might be indispensable. These experts are used to handling these kinds of troubles and can customize the footwear around the prominent navicular so it will be much more comfortable. A podiatric physician can frequently assist with all of this.

In the event the conservative non-surgical therapies tend not to decrease the symptoms, after that surgical procedures could be appropriate. Surgical procedures might require taking out the additional bone, re-shaping the spot and correcting the posterior tibial tendon to enhance its biomechanics. This extra bone is just not required for normal foot biomechanics, thus in theory it will not be an issue.