Vertigo - positional
Benign positional vertigo is condition in which a person develops a sudden sensation of spinning, usually when moving the head. It is the most common cause of vertigo.
Benign positional vertigo is due to a disturbance within the inner ear. The inner ear has fluid-filled tubes called semicircular canals. The canals are very sensitive to movement of the fluid, which occurs as you change position. The fluid movement allows your brain to interpret your body's position and maintain your balance.
Benign positional vertigo develops when a small piece of bone-like calcium breaks free and floats within the tube of the inner ear. This sends the brain confusing messages about your body's position.
There are no major risk factors. However, the condition may partly run in families. A prior head injury (even a slight bump to the head) or an inner ear infection called labyrinthitis may make some people more likely to develop the condition.
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