What is an OS Naviculare?

The accessory navicular (os navicularum or os tibiale externum) is an extra bone or piece of cartilage located on the inner side of the foot just above the arch. It is incorporated within the posterior tibial tendon, which attaches in this area. An accessory navicular is congenital (present at birth).

What is a Type 2 OS Naviculare?

Type II is a secondary ossification center of the navicular bone and is also referred to as “prehallux”, accounting for approximately 50-60% of accessory navicular bones. It is seen over the medial pole of the navicular bone at between nine and 11 years of age (3).

Why do I have an accessory navicular?

The exact cause of accessory navicular bone is unknown; however, it may be related to an incomplete joining (fusion) of bones and connective tissue during development and/or an abnormal separation of affected bones and connective tissue.

What is a Type 3 navicular?

Type III, also known as cornuate or gorilliform navicular, is characterized by a very prominent navicular tuberosity resulting from bony fusion of the accessory ossification center with the tuberosity. Most cases are asymptomatic, but ANB may cause pain and tenderness in a small proportion (<1%).

What causes the navicular bone to hurt?

Fracture and arthritis are common causes of pain. Less common but other important causes of Navicular pain include ligament injury, irritation of low back nerves, and Accessory Navicular syndrome.

How common is os Naviculare?

Epidemiology /Etiology. The foot and ankle have numerous accessory ossification areas, with the most common being the accessory tarsal navicular bone which occurs in 4-14% of the population. It first appears in adolescence, with incidence of 4-21% in children.

Why do I have 2 ankle bones?

An os trigonum bone is a congenital malformation that develops before birth when one area of the tallus (ankle bone) doesn’t fuse with the rest of the bone during growth. When the bone doesn’t fuse properly, there’s an extra small bone in the ankle.

How do you heal navicular bone pain?

The following may be used:

1. Immobilization. Placing the foot in a cast or removable walking boot allows the affected area to rest and decreases the inflammation.
2. Ice. To reduce swelling, a bag of ice covered with a thin towel is applied to the affected area.
3. Medications.
4. Physical therapy.
5. Orthotic devices.

Which is the best test for a navicular fracture?

Plain radiographs are the best initial test in a suspected navicular fracture. Their sensitivity for identifying navicular fracture is low, however lateral and oblique radiographs provide the greatest chance of identifying a fracture. Rarely fractures of an accessory navicular bone (if present) are also possible and may be visible.

What kind of pain does an accessory navicular cause?

People who have an accessory navicular often are unaware of the condition if it causes no problems. However, some people with this extra bone develop a painful condition known as accessory navicular syndrome when the bone and/or posterior tibial tendon are aggravated.

Where is the accessory navicularum located in the foot?

The accessory navicular (os navicularum or os tibiale externum) is an extra bone or piece of cartilage located on the inner side of the foot just above the arch. It is incorporated within the posterior tibial tendon, which attaches in this area.

How does open fixation of the tarsal navicular work?

Open reduction and internal fixation of these injuries allow anatomic restoration of adjacent joint surfaces and preservation of length and stability along the medial column of the foot; intervention must not disrupt the already tenuous blood Supply of the tarsal navicular because of the associated risks of avascular necrosis and nonunion.