Information used by the brain to allow for balance and spatial orientation is provided by sensory input from proprioception (touch and joint position sense), vision (sight) and the vestibular system (gaze stability, head position and motion, orientation in space).Vertigo and dizziness are common symptoms reported by patients to doctors during their visits, and can be caused from a huge variety of different conditions affecting different systems within the body.
This article will focus specifically on vertigo resulting from disturbance in the vestibular system, what causes it, and how specifically trained manual therapists (Chiropractors, Physiotherapists and Occupational therapists) can help in its diagnosis and treatment.
First up, it is important to distinguish between the sensations of dizziness versus vertigo. Simply put, dizziness refers to a feeling of light headedness, faintness or unsteadiness. Vertigo on the other hand, has a spinning component and involves the perception of the word rotating around you or vice versa. Anyone who has ever had one too many glasses of wine before bed and then lay down to find the room spinning around them will be able to relate!
The vestibular system is housed in a bony case in your inner ear and is made up of a complex system of canals, ducts and highly specialised sensory cells.
The 3 semi-circular canals in each ear are specifically orientated so that each canal works as a pair with the opposing canal in the opposite ear, allowing synchronization between the ears.
In HEALTHY semi-circular canals the sensory organs sense rotational movement and ARE NOT sensitive to gravity. In front of the canals the bony casing of the inner ear houses the otolith organs which ARE sensitive to changes of head position relative to gravity and to acceleration and deceleration.
A healthy vestibular system provides the best information about spatial orientation to the brain and can compensate for possible deficits in proprioception and vision.
So what causes problems in the vestibular system?
Two broad categories can be used to simplify where problems arise:
- Central vestibular pathology
- Peripheral vestibular pathology
Central vestibular pathology is caused by problems in the brain or spinal cord which affect the vestibular system (i.e. stroke or insufficiency in the blood supply to various areas of the brain).
Peripheral vestibular pathology is caused by problems within the vestibular system itself, the nerve supplying it, or the surrounding tissues. Conditions here can range from tumors and bony problems, to infection of the nerve and structural changes in the complex structure.
Although some of these conditions have serious implications, a large proportion of vertigo can be attributed to simple changes in the vestibular system that can be readily treated with positional head maneuvers and vestibular rehabilitation therapy (VRT).
One of the most common causes of vertigo is known as Benign Paroxysmal Positional Vertigo (BPPV). BPPV is found in up to 50% of individuals over the age of 65 with vertigo, and increases in incidence with age. Recent research has shown women to be affected twice as often as men, although the reason for this is currently unknown.
In this condition, small crystals which belong otolith organs in the bony encased area in front of the semi- circular canals, break off and make their way into one or more of the canals. This causes the affected canal to become sensitive to changes of head position relative to gravity and causes desynchronization with the opposite ear leading to a spinning sensation.
BPPV may follow:
- Head Injury
- Infection of the vestibular nerve
- Unusual head positions
- Exposure to continuous jarring
- Bed rest
Common symptoms include:
- Sudden memorable onset with a change in position
- Waking from vertigo when rolling over in bed
- Brought on by changes in head position such as looking up or down, bending forwards and rolling over in bed
- The spinning comes in short episodes
- Episodes tend to relapse and remit
- A feeling of vague motion sickness and imbalance
The diagnosis of BPPV can be confirmed by trained therapists using quick head movements in specific planes which cause predictable, uncontrollable eye movements in specific directions (nystagmus).
Once confirmed it is easily treated using positional head maneuvers in specific sequences which guide the detached crystals out of the canals where they are causing a problem. The maneuvers used depend on the canal affected, and the most common is called “The Epley Maneuver”.
Head positioning maneuvers require a certain amount of bravery as they cause an exacerbation of the symptoms during the procedure which may last for a few minutes after treatment and leave you feeling a little woozy for a couple of days.
Correct diagnosis and effective treatment, however, ultimately results in an 80-90% cure rate! Many practitioners such as the extremely skilled and knowledgeable Richard O’Hara (with whom I received my training and gained much of my knowledge in this field) now run successful practices where a large proportion of the patients they see are successfully treated for BPPV.
Usually there is recurrence within 3-12 months, however the rate of recurrence drops with each subsequent treatment.
Certain other causes of vertigo can be effectively treated using various VRT’s when appropriate.
Due to the wide array of pathologies that can potentially cause vertigo symptoms, a thorough history, neurologic exam, occulomotor testing and gait assessment is essential in the assessment of people suffering with dizziness and vertigo in order to correctly identify the cause. Furthermore, it is not uncommon for individuals to be affected with more than one cause, often requiring a multi-disciplinary approach.
Nevertheless is it encouraging to know that in many cases when the cause is found to be benign, treatment is safe and incredibly effective!
If you are personally struggling with vertigo or any of the symptoms mentioned in this post, or if you know of someone else battling with the spinning, it is definitely worth finding a trained manual therapist you trust to take you through a thorough assessment and determine whether VRT or positional head maneuvers are appropriate for you!
Stop spinning, find your balance and get back to moving the way you should!
Move Well. Live Well.