What is Os Naviculare Syndrome?
An Os Naviculare is an accessory bone that is a common genetic variant. It is usually asymptomatic but can become inflamed causing Os Naviculare Syndrome. There are several different types of accessory bones and they are grouped according to their position, shape and relationship with the adjacent bone. The Os is closely related to the Tibialis Posterior tendon and the Navicular bone.
What are the symptoms of Os Naviculare Syndrome?
Patients will often present with a swelling on the medial side of the foot and complain of pain after periods of standing, walking or more significant exercise.
How is Os Naviculare Syndrome diagnosed?
Clinical examination is an important aspect of making the diagnosis but imaging modalities such as X-ray and MRI are helpful in also planning treatment.
How is Os Naviculare Syndrome treated?
Treatment will depend on the severity of the symptoms, the type of Os Naviculare and the site of inflammation. If symptoms are mild then patient education is often all that is needed. With more significant symptoms, various options are available. If an MRI suggests that there is inflammation between the os and the navicular then injection therapy is quite effective. Inflammation of an os sitting within the tib post tendon is more difficult to treat non-operatively but simple rest and orthotics can be helpful. If all non-operative measures fail, surgery to excise the os and repair the tendon has good outcomes.
