by Tyler Sponaugle, DPT
Benign Paroxysmal Positional Vertigo, better known as BPPV, or simply "Vertigo" amongst patient populations, is the most common disorder of the human vestibular system. It is frequently described as an intense spinning sensation brought on by changes in head position1. As the word "benign" suggests, the condition in itself is not life threatening, but depending on the intensity of the spinning sensation, the condition can put a person at an extremely high risk for falls, which can lead to significant injury and hospitalization. Patients often describe the condition as "debilitating" or "terrifying" due to the rapid onset and intensity of symptoms that are brought on by seemingly simple motions such as rolling in bed, standing up/sitting down, or even looking up1. In most cases patients being affected are afraid to move due to fear of onset of symptoms. This article will provide information into the structure of the vestibular system and the specific mechanical problems that bring about an episode of BPPV. It will also describe known treatments for the condition and the steps someone afflicted with BPPV can take to identify key symptoms and seek necessary treatment.
The vestibular system is a sensory system responsible for providing information regarding the orientation of the body in space and is a primary contributor to coordinating movements necessary to maintain a sense of balance2. The entire vestibular system shares the space of the inner ear with the auditory system, and though it can sit comfortably on top a pencil eraser, the effect the vestibular system has on the way the human body moves and interacts with the surrounding environment is quite profound. There many unique structures and mechanisms at work in the vestibular system, which provide data to the brain regarding the body's position in space. For the sake of brevity, this article will focus only on those structures that are directly involved in an episode of BPPV.
The primary structures of the vestibular system involved in an episode of BPPV include the utricle and the semicircular canals2. The utricle is a chamber in the inner ear lined with very sensitive hair cells. On top of these hair cells sit the proverbial “crystals” or “rocks” in your head. These rocks are made up of calcium carbonate and are essentially microscopic pieces of limestone referred to as Otoconia. The otoconia sit all together on top of the hair cells of the utricle, held together by a gel like substance. As the head accelerates or changes position, the otoconia move on top of the hair cells and create a shearing force on the hair cells, which in turn send a message to the brain alerting it of a change in position or acceleration3.
The semicircular canals are a set of 3 fluid filled semicircular tubes that are responsible for perceiving rotation or angular acceleration of the head2. When the head is turned, it will cause the fluid to accelerate and bend a sensory receptor mass called the cupula which in turn sends a signal to the brain regarding the direction and intensity of the acceleration. They are oriented so that in a specific plane of motion will stimulate only one canal (i.e. spinning in a chair will stimulate the horizontal canal, a front flip or backflip will stimulate the anterior canal, and a cartwheel will stimulate the posterior canal.)
In a normal functioning vestibular system, the utricle and semicircular canals operate primarily independent of one another. They are, however, located in very close proximity to one another, separated by only a thin membrane. In a case of BPPV, this thin membrane breaks down, along with the gel that holds the otoconia in a mass. With the right positioning and movements, the loose otoconia can leak out of the utricle and into the semicircular canals. The fluid in the semicircular canals has the consistency of honey or nectar and normally does not react to gravity3. When the loose otoconia, which are affected by gravity, leak into the canal, this causes a relative disruption and movement of fluid (think of dropping rocks into a well) that causes the cupula to send a false message to the brain that the head is moving. Since BPPV usually only affects one ear at a time, the false signal will not match the normalized signal of the opposite ear, or the visual input from the eyes. The discrepancy in signals causes brain to perceive a spinning sensation3. The brain then makes the eyes move in an attempt to keep them focused on the environment. These involuntary eye movements (or nystagmus) are what cause those individuals afflicted by BPPV to experience the hallmark “room spinning around me” sensation.
As stated previously, BPPV is the most common disorder of the vestibular system with occurrences in up to 2.4% of the population. It accounts for up to 20% of all cases in specialized dizziness clinics. It seems to be most prevalent in 50-70 year olds, but has been known to affect adults of all ages. Very rarely will BPPV affect children3. In the majority of cases, there are no symptoms or precipitating factors leading up to onset1. There have been increased associations of the disorder with certain triggering factors in recent research, including head trauma, history of migraines or inner ear infections, diabetes, osteoporosis, and prolonged bed rest2.
Treatment for BPPV
Any type of dizziness should be considered a serious medical symptom and should be evaluated by a physician. With that being said, there are a number of signs and symptoms that are unique to the dizziness experienced with BPPV. The primary symptom of BPPV is an intense feeling of the environment spinning around the individual that lasts for less than 1 minute. After the actual spinning subsides, the individual may experience a lingering feeling of nausea or imbalance up to several minutes. The symptoms are consistently brought on by quick changes in head position such as looking up, rolling over in bed, getting in/out of bed, bending over, or looking over one’s shoulder4. BPPV is not accompanied by hearing loss despite the proximity of the vestibular systems to the auditory system. There should not be any feeling of numbness or tingling, weakness, pain, or decreased coordination3. It is important to note that BPPV is a transient disorder and often resolves on its own after several days. However, treatment provided by an appropriate healthcare professional is highly effective and fast acting.
It is important for a person experiencing a possible case of BPPV to make an appointment with their primary care physician (PCP), to receive a diagnosis of vertigo. The PCP may do some preliminary testing with head movements to assess for nystagmus (involuntary eye movements), but will likely refer the patient to a physical therapist (PT) with specialized training in treatment of vestibular disorders.
Upon seeking treatment for BPPV following referral from a PCP, a new patient will likely fill out a questionnaire or outcome measure to allow the PT to better understand what activities or movements bring on episodes of dizziness. The pt. will then undergo a series of tests in sitting focused on eye movements to rule out any red flags such as stroke or other central vestibular dysfunctions. Vital signs will also be collected to ensure the dizziness episodes are not caused by changes in blood pressure.
Since the cause of BPPV is mechanical in nature, so is the treatment. The physical therapist will guide the patient through a variety of very specific positioning maneuvers (performed with patient laying on a mat table or plinth) in an attempt to reproduce a spinning sensation and to observe the subsequent nystagmus that presents with it. The clinic will likely have a specialized pair of goggles that will be placed on the patient and will assist the therapist in observing eye movements. Based upon the maneuver that stimulated dizziness and the direction of the nystagmus observed, the therapist will be able to pinpoint which canal the otoconia have drifted into.
Once the appropriate canal has been identified, the therapist will guide the patient through a series of maneuvers directed at guiding the otoconia back into the utricle by simply utilizing appropriate positioning and the effects of gravity. At each position, the patient may experience symptoms such as nausea or dizziness, once the symptoms subside, the therapist will wait 30 seconds before moving on to the next position3. This indicates that the otoconia have collected/settled in a specific portion of the affected canal and can be maneuvered with minimal residual debris. At the end of the treatment maneuver, the otoconia should be out of the canal and the patient will feel symptom free. A follow up appointment may be scheduled if symptoms persist or to ensure there is no immediate recurrence. When performed correctly, positioning maneuvers are 90% effective in resolving cases of BPPV within 2 visits or treatment sessions.
Due to the orientation of the canals to the utricle, 85% of BPPV cases involve the posterior semicircular canal primarily diagnosed via Dix-Hallpike maneuver4. This is evidenced by the therapist observing a nystagmus that beats upward and has a rotational component towards the affected side. Primary treatment is via the Epley maneuver
Lateral canal involvement is noted in 5-12% of BPPV cases1. It is known for producing a more intense spinning sensation and is often accompanied by nausea. It is primarily triggered by rolling over in bed. Diagnosed with sit to supine and rolling L and R tests4. Nystagmus will be purely horizontal and more intense toward the affected ear. Treatment in uncomplicated cases will be via a 270 or 360 degree barbecue roll.
Though there are several other possible causes of BPPV including anterior canal involvement and cupulolithiasis, occurrences are rare and explanation is beyond the scope of the article.
In conclusion, BPPV is a fairly common vestibular disorder that presents with intense, room spinning dizziness. Though it is benign in nature, in can lead to increased fall risk and is very debilitating at onset. BPPV is caused by a rather unique mechanical failure of the inner ear and will likely require a physician visit. Treatment of BPPV is highly effective and fast acting when performed by an appropriate healthcare professional.
1. Parnes, Lorne S., Sumit K. Agrawal, and Jason Atlas. "Diagnosis and management of benign paroxysmal positional vertigo (BPPV)." Canadian Medical Association Journal 169.7 (2003): 681-693.
2.Goodman, Catherine C., and Kenda S. Fuller. Pathology: implications for the physical therapist. Elsevier Health Sciences, 2014.
3.http://vestibular.org/understanding-vestibular-disorders/types-vestibular-disorders/benign-paroxysmal-positional-vertigo Accessed 4/14/16.
4.Hornibrook, Jeremy. "Benign paroxysmal positional vertigo (BPPV): history, pathophysiology, office treatment and future directions." International journal of otolaryngology 2011 (2011).