THE MEANING of the term "postural vertigo" has varied somewhat as applied by different observers. From a practical viewpoint and in the following discussion the term postural vertigo will refer to vertigo which occurs only when the head is in certain positions, or during the change into a certain position, but is absent in other positions.
A true postural vertigo is usually accompanied by reflex reactions affecting the skeletal muscles and the eye muscles and vegetative reflexes affecting blood pressure and the gastrointestinal tract. The eye movements, usually nystagmus, are used as the most convenient objective indicator of the disturbance.
The existence of a postural vertigo as distinguished from vertigo which is spontaneous and present in all positions can usually be determined by a careful history. The postural character of the vertigo may be overlooked if it is not elicited by careful questioning.
Postural Tests.—A series of postural tests