My PT background is in outpatient orthopedics with an
emphasis on movement re-education and like many rehab clinicians, I possess a
natural wonder of the vestibular system. I marvel at the capacity of the human
movement system with it’s ability to produce poetic motion - the trapeze artist
flying through the air upside down never losing orientation of their partner’s
outstretched arms, the flyboarder performing back flips and landing on pillars
of water, or the prima ballerina spinning endless fouetté turns en pointe. And not to be out done by such levels of
dynamic brilliance, the mundane can also be marveled - the balance,
coordination and strength needed to get up off the floor is a valid sign for
longevity. Now that is important! My appreciation
of this “wonder” led me to registering for this 6-day advanced competency-based
course in 2014 with Susan J. Herdman, PT, PhD, FAPTA sponsored by the Department of Rehabilitation Medicine, Emory University School of Medicine.
Thoughts on the 6-day
competency-based course format
This 6-day course required prior knowledge and experience of
vestibular disorders. The multi-disciplinary instructors come from all over the
country and are all experts in vestibular evaluation and rehabilitation
providing an enriched environment for learning. I found them not only
responsive to questions in class but also with follow up emails after the course
was over.
There was a good balance between group lectures and
demonstrations that took place in the large lecture hall and break down groups
for practicums led by different instructors in smaller conference rooms. Case
study presentations were a constant all week - those and video presentations
really helped improve my differential diagnostic skills. Competencies were
performed in the evenings and we completed a video and written exam at the end
of the week.
Much like other clinical presentations, there are often
multiple facets that make up each vestibular case, so honing skills and
clinical reasoning to assist in identifying and understanding such nuances is a
sign of an improving skill set. At the
end of this 6-day course I now have a deeper understanding of managing this
particular patient population and am able to connect the dots better with
respect to the clinical reasoning behind specific presentations. Although I
have a long way to go to fill in the gaps of my knowledge related to neuroscience,
this course definitely helped me gain more clarity in examining, evaluating and
treating vestibular disorders.
Summary of my “aha” moments and clinical pearls
1. I was fascinated to learn that the size of a dime covers the contents of each labyrinth containing the semi circular canals (SCCs), the utricle and saccule as well as the cochlea.
2. In order to experience vertigo (the
sensation of movement when there is no movement) – you have to have a “rapid onset of asymmetrical neural activity”,
otherwise central compensation has time to kick in as the system can adapt to
slow changes over time.
3. Identifying the
less common presentation of horizontal BPPV canalithiasis (5% of BPPV cases).
While performing the Roll Test on a
patient whose subjective examination pointed toward BPPV, the patient
demonstrated clear geotropic nystagmus on the left side greater than the right
that attenuated while in the test position. Being able to identify the
direction and interpret the nystagmus correctly allowed me to diagnose the
patient with left horizontal canal BPPV canalithiasis and treat him
successfully with the BBQ roll.
4. Effectively
progressing gaze stabilization (VOR adaptation) training.
For patients with unilateral
vestibular loss (UVL) due to vestibular neuritis gaze stabilization training
using treatment variables such as duration, frequency, speed, background
motion, distance and more challenging bases of support can help promote
vestibular compensation. This patient population generally has a favorable
prognosis due to central compensation.
5. Recognizing the
characteristic wide-based, slow and ataxic gait, complaints of oscillopsia and
dizziness, increased postural instability in the dark with the patient with
bilateral vestibular loss (BVL).
Though this condition has several
etiologies exposure to ototoxic medication is the most common cause and generally
the prognosis is not as good as UVL but through substitution tactics patients
can make surprising gains in balance though they will always have difficulty
walking in the dark.
6. Recognizing that
vertigo or dizziness related to Migraine headaches can occur with or without a
headache. Treating the Migraine headache
is the primary intervention so appropriate referral or follow up with the MD is
essential.
7. Understanding Alexander’s
Law is one component that has
improved my understanding of peripheral versus central nervous system
presentations.
Peripheral presentations - follow
Alexander’s Law and nystagmus is mixed plane – horizontal & torsional
Central presentations – nystagmus can be
pure torsional, pure vertical or direction changing with change in direction of
gaze
8. Dizziness
associated with concussion or head trauma has several possible etiologies that
can be central and/or peripheral in nature and the symptoms are usually the
result of a combination of issues. If vertigo due to BPPV is present it is not
part of the concussion rather because the otoconia have been displaced from
otolithic membrane due to the actual head trauma.
9. Recognizing the
need to have video goggles to assist with the accuracy of the diagnosis of the
type of BPPV including the identification of the involved canal. This tool
assists in evaluating nystagmus beyond the acute phase where compensation with
fixation is present (no goggles) but may still be present when fixation is
removed (goggles on with darkened visual field). Ultimately this helps guide
the appropriate and most effective treatment.
Other diagnoses discussed during the course included
Meniere’s disease, motion sensitivity, cervicogenic dizziness, chronic
subjective dizziness, dizziness related to psychological diagnoses, central
nervous system pathologies, orthostatic hypotension and other more rare
presentations such as perilymph fistulas.
Below is the website for Vestibular Disorders Association
(VEDA) which I have found informative as a clinician and for patients as well
as a link for the aVOR app a fun-learning tool.
aVOR app:
Reference: Herdman Susan, J. Vestibular Rehabilitation 3rd edition. Philadelphia, PA: F.A. Davis Company;2007.
Blogpost by Tracey Wagner, DPT, OCS, FAAOMPT
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