Several diseases and disorders affecting the inner ear or brain or certain medications may cause balance disorders. The causes may vary from infections (viral or bacterial), head injury, disorders of blood circulation etc.
Those who have injuries or illnesses of the eyes or have problems with the skeletal system (e.g. arthritis) may also experience balance difficulties. These disorders may lead to a conflict of signals to the brain about the sensation of movement and can lead to balance problems.
If there is a conflict of signals between the eyes and the brain, for example, if a person tries to read while riding in a car, there is motion sickness. Some symptoms of motion sickness include dizziness, sweating, nausea, vomiting, and generalized discomfort.
Main causes of balance disorders
Broadly classifying balance disorders may occur due to problems in any of the four areas:-
- Disturbances of the labyrinth in the inner ear – Peripheral vestibular disorder
- Disturbances in the brain or its connecting nerves - Central vestibular disorder
- Problems of the body other than the head and brain – Systemic disorder
- Blood flow problems or Vascular disorder
Types of balance disorder
Some of the different types of balance disorder leading to impaired sense and maintenance of balance include:-
Benign Paroxysmal Positional Vertigo (BPPV)
This condition is characterized by brief but severe episodes of vertigo brought about by specific positional change of the head. The movement could be trivial for example rolling within the bed or trying rise up to a sitting position from lying position or even looking up at an object.
It is found that movement of chalk crystals (otoconia) within the inner ear from one part of the balance system (utricle and saccule) to another part of the balance system (semi-circular canals) due to movement of the head gives rise to the symptoms.
Although the exact cause of the condition is unknown, it is thought to be caused as a part of normal aging, infection or head injury.
Ménière's disease
This is caused by an imbalance between the pressures of the fluids within the inner ear. The exact cause is unknown. There are episodes of vertigo, hearing loss and sensation of fullness in the ear along with tinnitus (a ringing or roaring in the ears).
Labrynthitis
This is caused by infection and/or inflammation of the inner ear causing dizziness and loss of balance.
Vestibular neuronitis
This is caused by an infection of the vestibular nerve caused by a virus. There is generally rotatory vertigo (horizontal or vertical spinning) that may last for up to 48 hours, exacerbated by movement.
Perilymph fistula
In this condition there is leakage of inner ear fluid to the middle ear. This occurs due to head injury.
Other causes of balance disorders
Certain medications that depress the central nervous system may also increase the rate of falls by increasing the lack of coordination.
Arthritis, joint pain, stroke, visual impairment, back or neck pain, myelopathy due to cervival spondylosis, normal-pressure hydrocephalus, parkinsonism and fall of blood pressure on standing (orthostatic hypotension) are other causes of balance problems and risk of falls among the elderly.
Problems in the cerebellum of the brain also contribute to balance disorders.
Further Reading