Systematic Review: Manual Therapy for Cervicogenic Dizziness

This systematic literature review investigates the effectiveness of manual therapy (MT) for cervicogenic dizziness (CD), a condition characterized by dizziness and imbalance related to neck movements. The review explores the rationale for MT in alleviating CD symptoms, which can stem from whiplash and other causes. The study design involves randomized allocation to either sustained Glides (SNAG) or placebo groups, with interventions administered by experienced physiotherapists. Participants underwent screening by physiotherapists and neurologists to confirm CD diagnosis, utilizing various assessment tools such as the Dix-Hallpike maneuver and cervical range of motion tests. The study measures primary outcomes using a visual analogue scale (VAS) for dizziness and secondary outcomes using a 6-point dizziness scale, Dizziness Handicap Inventory (DHI), neck pain VAS, and a cervical range of motion device. Data analysis includes sample size calculation and t-tests to compare the treatment groups. The review aims to determine the usefulness of MT in preventing CD signs and associated pain, comparing different MT approaches and assessing their impact on balance, cost-effectiveness, side effects, and treatment gratification.

Running head: A SYSTEMATIC REVIEW 1
A Systematic Literature Review
Student’s Name
University of Affiliation

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Usefulness of Manual Therapy for Individuals with Cervicogenic Dizziness (CD); A Systematic
Literature Review and Metal Analysis
Abstract
For the past two decades, there had been a heated debate regarding the existence of
cervicogenic dizziness (CD) and as of late, report and studies have provided proof in favour of
its existence (Bodes-Pardo et al., 2013). Dizziness is a common problem among people that
usually leads to physical complications like falls, unsteadiness and social/emotional/financial
problems. Although there are myriad causes of dizziness, the most common cause is dysfunction
or complications in the upper cervical spine. Björklund et al., (2012) asserts that this condition is
where cervicogenic dizziness comes in, a condition characterised by unsteadiness or imbalance
related to positions or movements of the neck. The symptoms of the condition can range from
neck stiffness or pain to general weakness plus psychological issues like poor memory, lack of
concentration or anxiety. Although there is no known treatment for treatment of CD, studies
show that manual therapy (MT) can help alleviates the problem (Bronfort et al., 2010). It has
been observed that about a third of people with the condition have their onsets as a result of
whiplash, spinal degeneration and other causes.
Statistically, whiplash is experienced by a population of 0.2% where the incidences of
dizziness in the victims have escalated from 19 to 59%, 42 to79% and as high as 82 to 93%. In a
study conducted in Maryland University in 2006, individuals with whiplash associated dizziness
(n=106) were reported to have a higher joint position errors plus neck pain index compared to
the control treatments n=42. However, in 1992, Mulligan Brian developed manual therapy for
the treatment of CD referred to SNAG, Sustained Apophyseal Glides (D’Sylva et al., 2010).

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Since the treatment is widely used by physiotherapists, little research has been done to access the
effectiveness of CD.
The rationale of this systemic review with metal analysis is to provide a review and
discuss the usefulness of MT in preventing signs of CD plus the associated pain. It will compare
the effects of two manual therapies as well as to the placebo intervention. Other objectives will
be to identify the impact of intervention on head balance and repositioning, identify the cost
usefulness of the intervention, report the common side effects, and treatment gratification.
Design/Methods
Participants were randomly allocated to the sustained Glides and placebo groups. Every
participant received up to five treatments by a professional physiotherapist over 42 days over the
discretion of treating therapists used clinical judgement to identify the dosage as per the client’s
response. The treatments stopped when the participants that the condition was adequately
improved or when where was o further improvement over two continuous visits.
Participants/recruitment
90 participants with CD were recruited in Canada through press release as well as radio
interviews/ newspaper blogs, via advertisement in daily newspaper, plus referral from healthcare
professionals like neurologists. Hence forth, exclusion and inclusion criteria were summarised as
shown in the table below.

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Screening of participant by a healthcare
professional, physiotherapist
Participant assessment
(physiotherapist)
Assessment by a neurologist
Assessment Baseline
CRA, concealed random allocation
SNAG & self SNAG
house workouts
Deactivated lasers
of the placebo
Blind examination, post treatment, 42, days, 3months, 0.5 years and I year
Extraction
Extraction
Extraction

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Exclusion and inclusion criteria
Exclusion criteria: Conditions that would put an individual at risk of CD
Exclusion criteria Inclusion criteria
Inflammatory joint disease Has CD described as imbalance related to neck
movement /positions
Marked osteoporosis Has the symptoms present for more than three
months
Cervical spine cancer 18 to 90 years old
Pathology of the spinal cord
Dislocation of the neck
Acute nerve root symptoms
Marked cervical spine disc protrusion
Participants Screening for CD
A process of three steps was used in identifying those with CD. First, an initial
screening of phone was done by a physiotherapist. Second, for the potential participants who
were perceived to posses the condition following a discussion regarding the phone, were
physically tested by a professional physiotherapist. Lastly, those not excluded by a
physiotherapist at this stage had an examination which was clinical and it was performed by a
neurologist like function testing of peripheral vestibular.
Screening of phones
In this process, history of the individual was taken by a physiotherapist to identify that
the client did have CD. If the client had other types of dizziness like orthostatic hypotension and

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vertigo they were left out. In cases where dizziness was termed as CD (unsteadiness or
imbalance) it was noted that the later was not as a result of another cause suck as
musculoskeletal or neuromuscular complications. However, it was noted that there was a related
past of neck stiffness or pain. The poor balance or lack of steadiness was also due to cervical
spine positions or movements.
Professional physiotherapist assessment
The Dix-Hall pike manoeuvre was conducted to know whether the individual had their
phones screened and those thought to be CD positive if they underwent a physical examination
done by a physiotherapist. The examinations were;
1. The Dix-Hall pike manoeuvre conducted to know whether the individual had dysfunction of
semi-circular canals. Here, the participants sat on an examination table and the health care
proffesional the participant head to an angle of degree 45 and quickly laid the participants with
their back straight such that the head was extended below the horizontal. Ideally, the nystagmus
formation was a presence of benign paroxysmal vertigo.
2. A hypertension test was done in sitting and upright position using a sphygmomanometer.
However, the normal response of pressure to positional change was an indication that
neurocardiogenic syncope was not likely a cause of CD.
3. Smooth visual pursuit movement was also done to track slow moving objects. The one
examining looked for eye movement asymmetry which may show the presence of cerebella
lesion.
4. The cervical range of motion was also done to know if the participants have a limitation of
movement which might be a good indication of cervical spine dysfunction with CD. Here,

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participant was requested to sway the neck into a reflexion, right and left rotation, extension as
well as right and left lateral reflexions as well as report in case of symptoms like pain or
dizziness.
5. Palpation on the upper cervical spine was also tested to identify painful or stiff joints. In case
of these symptoms, there would be an indication of complication in the upper cervical spine.
6. Lastly, a decrease of balance was shown in individuals with CD. For assessing balance, the
participants were balance used to assess posture steadiness in a heel to toe posture. They were
asked to be in tandem posture for 30 second. This is a standing balance of clinical measure used
to test steadiness in a heel to toe posture.
Neurologist’s Examination
For the participants who were not excluded in the performance of previous screening,
were also tested by a neurologist to eliminate the CNS and vestibule. The examination included
tests of vestibule-ocular and spinal function as well as testing of balance
Randomisation
Participants who were not eliminated in process of screening were allocated randomly to
either placebo or Mulligan SNAGS. A statistician who was independent produced a pattern
generated using a computer which was then put in envelopes sealed in sequential numbers. This
pattern contained participant’s number for every group.

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Interventions
Intervention was performed by a manual therapy specialised professional physiotherapist
experienced in a period of 10 yrs at minimum.
Placebo
A participants group had placebo interventions comprising of infrared therapy laser that
the manufacturer had deactivated. Physiotherapists use medical lasers to treat symptoms of
musculoskeletal. To the participants, the device of the laser seemed to function normally with the
flashing light as well as sound of beeping but did not give effective emissions. However, the
laser which was deactivated that appeared to show a strong effect of placebo was applied for 120
seconds for each neck’s side, with a pen at a distance of one centimetre from the skin.
Mulligan Sustained Apophyseal Glides
Another participants group received SNAGS as Brian Mulligan presented. A participant
in a sitting posture was asked to sway his head in a direction that emits the symptoms. As the
head of the participant moved, a physiotherapist glided the C2 or Ca vertebra anteriorly plus
sustained the glide via the movement. During the glide application, the participant was supposed
to be symptom free as well as allowed to stop in case dizziness was produced. Ideally, the
movement was repeated severally during the initial recommended treatment session by Brian. In
the other treatments where there we no dizziness, an apophyseal Glides was performed done
severally and pressure applied. The other sustained glide in a different showed that the direction
of movement would be included to the treatments. Following this treatment, the participants

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were asked to perform a self apophyseal Glides daily as a workout plan where the participants
were asked to do home exercises once daily for a period of one year.
Outcome Measures
Social-demographic data of the participant was gathered at the baseline which included
the participants’ gender, age as well as time following the start of dizziness. Both outcomes
(primary and secondary) were measured at the baseline following the final treatment at 6, 12 and
24 weeks respectively plus one year upon completion of the treatment. Follow up assessment
was done by analysts blinded to participant’s group allocation.
Primary Outcomes
The extent of CD was measured with 100mm VAS, visual analogue scale. The scale had
measure dizziness in other studies successfully.
Secondary Outcomes
1. The rate of dizziness was determined using a 6-point point scale that included the following; 0
to mean no dizziness, one was dizziness less than once per month, two to mean one to four
episodes of dizziness in a month, three to mean one to four episodes of CD a week, four to mean
one dizziness in a day, and five dizziness constant dizziness. This scoring technique had been
used by multiple researchers to measure the rate of dizziness.
2. Disability due to dizziness was assessed using DHI, a dizziness handicap inventory tool. It
measured the type of life using a subscale to show the effect of CD on a person’s day to day
activities. Ideally, 100 was the highest score and represented the limit self perceive handicap.

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3. The seriousness of neck pain was examined using a 100mm visual analogue scale. However,
there is lots of evidence holding to a greater validity of scale for assessing the level of pain.
4. Neck repositioning sense was assessed using a cervical range of motion device. This was
aimed at testing a person’s capability to reposition both the neck and the head. However, the
participants sat with heads in a neutral posture. Then they were advised to close the eyes as well
as rotate their head. However, at a half range rotation, they were ordered to stop, held their head
steadily thought about the position, a target position. After five seconds, they returned to the
initial posture where a reading was taken. The difference in degree between the target posture as
well as the attempt to get it was determined. This was done three times for left and right rotation
plus the mean obtained for every direction of rotation.
Analysis of Data
1. Sample Size (N) Calculation
The needed sample measurement was based on analysis, with t-tests for the variation of
treatments group pairs and alpha set of 5%. A comparison between the placebo and SNAG
group was made. Sample size calculation was based on variation of the above groups which
would be important for the results, supported by findings of other studies where there were
applicable data. This was done by biostaticians from Newcastle University using VAS and DHI
as the outcome measures. The later was an outcome measure for calculation of the sample size
since it is a great measure of perceived disability as well as impact of dizziness on function.
However presuming that the s.d of dizziness handicap inventory score was 14 and then about
thirty participants in every group would give the study an eighty percent power to find the
variation of eleven units in every group. The participants (30), in every group were also required

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basing on the zero to ten VAS scale with a s.d of 3.2 plus a significant variation of two and a
80% power plus 5% C.I
2. Statistical Methods.
For the primary outcomes measures of dizziness handicap inventory, the resulting
variables were the dizziness handicap inventory while predictors were treatment groups and
time. A probability value for the interaction term would represent in case of difference in
variation in the dizziness handicap inventory overtime of the groups. However, a “gate keeper’s
technique” was employed to check for the different testing plus limit the whole type 1 error. This
implies that a SNAG intervention would be tested for the placebo. Both primary and secondary
outcomes were also compared in the treatments at every point with t-tests.
3. Economic Assessment
Economic assessment varies from one outcome to the other. There is a possibility that
variation in effectives would exist, hence a cost utility and effective analysis would be necessary.
In the event an intervention was very useful but cheap, the incremental cost effectiveness ratio
would not require any calculations since the most efficient effective intervention is usually
preferred. In case the results showed that one intervention was more effective than the other, a
cost minimisation analysis would be necessary. However, in the scenario presented, there was no
difference in the efficacy hence the analysis was a comparison of the costs.

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Control of Bias
To limit bias randomisation certain exclusion and inclusion criteria, blind data analysis,
and concealed allocation would be employed. Besides, it is very hard to blind physiotherapists
during intervention.
Discussion and Conclusion
Participants experienced increased dizziness and neck pain in the baseline phase thus
making it hard to interpret the results. Besides, a self perceived disability was very stable in the
baseline despite the fact that it increased in the final measurement. The cervical range of motion
declined during the baseline phase apart from rotation to the left which increased. Considering
the unstable baseline, it is evident that one should be keen enough when interpreting the results.
Therefore, it appeared be a tendency of the intensity dizziness as well as perceived disability to
lower in later treatment section with the reduction in intensity being clinically and not
statistically of essence plus the reduction in perceived stability being statistically and not
clinically important. Neck pain was considered minimal in the last treatment with the decline
being clinically significant. All in all, the decline wasn’t statistically significant neither was it
kept at follow-up. Also, the treatment did not appear to have any effect of on active cervical
range of motion.
In conclusion, this review has outlined the usefulness of MT treatment for individuals
having CD as well as neck pain to some extent. It has compared its efficacy plus cost
effectiveness of placebo and SNAG intervention in lowering CD symptoms plus its pain over
one year. The aim of the review was to show which manual therapy treatment is very effective
for such conditions (CD) and if manual therapy is efficient in the long run. Ultimately, the