At Blackberry Clinic our practitioners hold regular training meetings to share and impart knowledge they have to each other, to keep up to date with new skills and treatments and to offer support and advice to each other about difficult cases. This is known as Continuous Professional Development or CPD and every medical professional has to complete a certain number of CPD hours to satisfy the requirements of their registration.
The meetings can be practical or in the form of lectures or case studies. Shelley Terry, our chiropractor at Blackberry Clinic Milton Keynes recently gave a lecture about dizziness and vertigo to her colleagues, covering the science and diagnostic methods as well as treatment options for this debilitating and distressing condition.
If you suffer from a painful and debilitation musculoskeletal condition we can promise you that our highly skilled professional team are here to help you, to diagnose the cause and offer treatment and investigation if necessary.
We offer a musculoskeletal medicine service that is unique in the UK, offering interventional pain medicine, injections, sport and exercise medicine, physio, osteopathy and chiropractic all under one roof at Milton Keynes, with varying services on offer at our 9 other Blackberry Clinics around the UK.
The following information is for education purposes only and should in no way be used to self-diagnose or treat any of the conditions listed below. Should you be suffering with any of the symptoms discussed below, please seek medical advice.
Shelley Terry, Chiropractor Blackberry Clinic Milton Keynes
CPD lecture – Shelley Terry – Blackberry Clinic Milton Keynes – October 2020
There are many potential causes of dizziness which include:
- Vestibular neuritis – superior division of the vestibulocochlear nerve can be affected by an infection. 3.5 per 100,000.
- Sudden onset of vertigo, oscillopsia, nausea, vomiting and veering to one side. This generally peaks from minutes to hours after the onset. There is generally no hearing loss, but motion sensitivity can last for months.
- Due to viral infection – resting potential of the nerve is affected causing asymmetrical activity between each ear.
- BPPV often occurs after vestibular neuritis.
- Can cause typical peripheral nystagmus
- Usually takes 3 months to settle and is improved with vestibular rehabilitation
- Meniere’s disease – intermittent episodes of vertigo, hearing loss, tinnitus, and aural fullness.
- Lasts between 20mins and 24hrs
- Pathology is not fully understood
- End stage of the disease – severe hearing loss, constant tinnitus (fluctuates), constant mild disequilibrium. 10-15 yrs after onset
- Not helped by rehabilitation exercises generally
- Migraine
- 33% of migraine sufferers have vertigo.
- Abnormal neuronal activity in the Central Nervous System
- There are conflicting theories of migraine’s relation to vertigo
- Vestibular rehabilitation exercises can help
- Central causes
- Central causes can cause vestibular symptoms
- Any lesion affecting the pathway from eyes to brain and back can cause vestibular symptoms
- If the posterior inferior cerebellar artery which supplies brain stem, it can result in stroke (Wallenburg’s syndrome)
- Vertebrobasilar Artery Insufficiency – patients do not normally suffer from dizziness or vertigo in isolation. Symptoms normally transient but can be affected by neck position.
- Vertigo initial symptom in 48% of patients
- Less than 1% of patients presented with one symptom alone (Caplan et al 2004, Grad and Baloh 1989)
- Bilateral vestibular failure can be caused by tumours, infection, Pagets disease, Polyneuropathy, Otoxic medication.
- Does not cause spinning as the failure is bilateral
- Perilymph fistula
- Semicircular canal dehiscence – when the bony labyrinth is thin in the superior canal it can sometimes become continuous with the CNS
- Acoustic Neuroma/vestibula schwannoma – hearing loss and tinnitus.
- Hearing loss is progressive from onset
- Imbalance and vestibular symptoms are most often prominent when tumours are large due to central adaptation to the slowly evolving lesion
· Psychological problems
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- Panic disorder
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· Elderly
So, what is the function of the vestibular system?
It senses acceleration and deceleration for a number of reasons
· Gaze stability – the vestibule-ocular reflex (VOR) drives eye movement to keep gaze stable
· Postural stability – through the vestibule-spinal reflex
· Orientation in space
· Autonomic nervous system
The vestibular system in each inner ear is made up of three semi-circular canals and two pockets, called the otolith organs, which together provide constant feedback to the cerebellum about head movement.
All of these canals contain the cupula which senses rotary acceleration and deceleration as the endolymph surrounding the cupula and the cupula has the same relative density.
Reciprocal inhibition also works with the semi-circular canals – rotation in one direction causes excitation of one canal and inhibition of the other.
The semi-circular canals are bi-directionally sensitive i.e. with only sense one direction or the other and not in-between.
The VOR is present with head movements over 0.5-0.7Hz
Smooth pursuit eye movements are generated centrally (brain) and function at lower frequencies.
Otolith organs – sensitive to changes of head position relative to gravity. They are sensitive to linear acceleration/deceleration
• Healthy semi-circular canals are not sensitive to gravity.
• Otolith organs are sensitive to gravity.
Nystagmus
Rhythmic eye movement that normally consists of a fast phase and slow phase. The fast phase usually dictates the side of the lesion.
Very rarely nystagmus can be congenital.
There are two main types of nystagmus – Central and Peripheral
· Central can be caused by central pathology. Always assume a central cause until proven otherwise.
· Central nystagmus is not suppressed with fixation
· Central is a pure beat – pure up, down or torsion
· Peripheral is suppressed by fixation
· Peripheral is mixed (horizontal/torsional)
· Follows Alexanders law
· Enhanced with head shake
· Beats towards the more active ear
Alexander’s Law
• Nystagmus beating in one direction
• Faster nystagmus with gaze in the direction of the fast phase
• 1st ,2nd, or 3rd degree intensity
Benign Paroxysmal Positional Vertigo – BPPV
BPPV occurs when Otoconia become dislodged and float freely.
Free floating otoconia enter one or more of the semi-circular canals which causes the canals to become sensitive to changes of head position.
Canalithiasis – when mobile otoconia are within a semi-circular canal (Epley 1995)
Cupulothiasis – when the otoconia adhere to the cupula
Subjective findings:
• Sudden memorable onset with change of position
• Vertigo often wakes the patient as rolls over in bed
• Short duration – true rotational vertigo
• Precipitated by changes of position
• Follows relapsing, remitting course
• 50% of individuals over 65yoa
• Women affected twice as often as men
• Increasing incidence with age
May follow head injury, vestibular neuritis, unusual head positions, bed rest, exposure to continuous jarring
The posterior canal is affected 91% of the time, horizontal canal affected 8% of the time and the anterior accounts for 1%
Diagnosis is by use of manoeuvres to test the position of sensitivity:
· The Dix-Hallpike test
· The Side Laying test – anterior or posterior canals
· Roll Test – horizontal canal
Treatment manoeuvres
Subject to positive findings with the above tests, there are a variety of manoeuvres that can be used to treat BPPV:
Epley – for canalithiasis
Semont – for cupulothiasis
BBQ roll – horizontal canal
Success rates:
Between 70-90%
Recurrence rate 30% within 6 months (Amor-Dorado et al 2012)
Post treatment instructions – no firm evidence to support specific post treatment protocols.
Rehabilitation Exercises
· Cawthorne-Crooksey Exercises
· Adaptation X1 and X2
· X1 = head movement, stable object
· X2 = head movement and target movement in opposite direction
· Adaptation
· Image needs to be maintained clearly
· Head movement around 30 degrees
· Smooth continuous movement
· Head movement fast enough to challenge the patient
· Vertical and horizontal movement
· Variables to alter – speed, duration, background, position, distance, target size, frequency, challenge balance, introduce cognitive challenge
· Start low intensity, low frequency as patient may become overwhelmed and get worse – start 1 min 2x per day
· Symptoms usually improve by end of week 2-3
· Central vestibular disorders can be treated with adaptation and habituation exercises but the evidence is limited
· Balance rehab must also be considered
Cervicogenic Dizziness
· Proprioceptive information from the cervical spine synapses with the vestibular nuclei.
· Cervical reflexes supplement the vestibular reflexes such as the cervico-ocular and cervico-spinal reflexes.
· Treatment for cervicogenic dizziness assume that potentially dangerous conditions have been ruled out first.
· Experimental interference with cervical spine proprioception reduces balance and equilibrium.
· Treleaven (2003) – studies whiplash patients and came to the conclusion that cervical proprioception is reduced in patients with musculoskeletal cervical spine dysfunction.
· No validated test for cervicogenic dizziness. But neck re-location test (CPROM) useful as a measure.
· There is no indication that neck mechanoreceptor dysfunction causes true vertigo.
· More research into cervicogenic dizziness required.
