Benign paroxysmal positional vertigo (BPPV) is a condition characterised by episodes of sudden and severe vertigo when one’s head is moved around. Common triggers include rolling over in bed, getting out of bed, and lifting the head to look up. BPPV is caused by particles within the vestibular system of the inner ear. Usually, BPPV affects only one ear.
Vertigo may be used to describe feelings of dizziness, lightheadedness, faintness, and unsteadiness. The sensation of movement is called subjective vertigo and the perception of movement in surrounding objects is called objective vertigo.
The most common cause of dizziness is BPPV. Others include: Inflammation in the inner ear, Meniere’s disease, neck joint dysfunction, vestibular migraine and acoustic neuroma. Rarely, vertigo can be a symptom of a more serious neurological problem such as a stroke or brain haemorrhage. Under age 50, head injury is a common cause. Vestibular viruses can also play a role. BPPV can also be a result of surgery due to prolonged supine positioning and possible trauma to the inner ear.
The symptoms of BPPV can include:
Sudden episodes of violent vertigo which may last half a minute or more.
Dizziness and/or nausea.
Movements of the head trigger the vertigo.
The eyes may exhibit nystagmus.
BPPV is caused by otoconia (calcium carbonate crystals) moving from the maculae of the inner ear into the fluid-filled semicircular canals. The peripheral vestibular labyrinth contains sensory receptors in the form of ciliated hairs in the three semicircular canals and in the ear’s otolithic organs. They respond to movement and relay signals via the eighth cranial nerve. Visual perception such as gravity, position, and movements also receive signals from somatosensory receptors in the peripheral vestibules. With the displacement of the otoconia into the semicircular canals, these delicate feedback loops relay conflicting signals that can result in any symptom related to BPPV. It is thought that injury or degeneration of the utricle may allow the otoconia to dislodge and escape into the balance organ and interfere with the vestibular system, however most cases of BPPV are idiopathic.
There are two types of BPPV: one where the loose crystals can move freely in the fluid of the canal (canalithiasis), and, more rarely, one where the crystals are thought to be ‘hung up’ on the bundle of nerves that sense the fluid movement (cupulolithiasis). With canalithiasis, it takes less than a minute for the crystals to stop moving after a particular change in head position has triggered a spin. Once the crystals stop moving, the fluid movement settles and the nystagmus and vertigo stop. With cupulolithiasis, the crystals stuck on the bundle of sensory nerves will make the nystagmus and vertigo last longer, until the head is moved out of the offending position. It is important to make this distinction, as the treatment is different for each variant.
Once the healthcare provider knows which canal(s) the crystals are in, and whether it is canalithiasis or cupulolithiasis, then the appropriate treatment maneuver can be carried out.
Our physiotherapists at Motion Health are well placed to diagnose and treat BPPV using otoconia replacement techniques. Ascertaining whether or not there is a cervico-genic component to the patient’s symptom pattern is also important.
A test we commonly use to determine the unilaterality of BPPV is the Dix-Hallpike test.
To check for right side involvement, rotate the patient’s head to the right 45 degrees while in the long sitting position (this aligns the right posterior semicircular canal with the sagittal plane of the body).
The examiner grasp the patient’s head and quickly moves the patient to the supine position with the neck slightly extended (ear down position).
The examiner checks for nystagmus. If present, note the latency, duration, and direction (should not last more than 1 minute).
Once we have determined that the loose crystals can move freely in the fluid of the canal (canalithiasis),a commonly used treatment technique is the Canalith Repositioning Procedure or Epley manoeuvre. We may need to complete this manoeuvre over 1 to 3 visits in order to obtain complete resolution of symptoms.