An Introduction to Vestibular Rehabilitation – Sarah Lamb Catalyst Kinetic Groups
In this blog post, we had the opportunity for Sarah Lamb from Catalyst Kinetics to come in to present to us on Vestibular rehabilitation. Sarah is currently a practicing physiotherapist who graduated from UBC with a Masters of Physiotherapy in 2013. Since then, she has been trained and specialized in vestibular rehabilitation and treats patients with concussions who suffer from vestibular dysfunction. She has kindly come in to share her knowledge in the assessment of the vestibular system and exercises that can help address and improve related symptoms! Before assessing the vestibular system, it is important to understand the difference between dizziness and vertigo.
Dizziness can be defined as:
➢ Light head, swaying, off-balanced, motion sickness symptoms
Vertigo can be defined as:
➢ the illusion of movement in the environment
Understanding the differences allows us to more clearly distinguish an individual who may have vestibular disorders which usually entails having symptoms of both vertigo and dizziness.
In individuals with vestibular dysfunction, we can observe the following signs and symptoms:
➢ Nystagmus (involuntary rhythmic movement of the eyes)
➢ Poor Gaze Stability
The vestibular system consists of the bony and membranous labyrinth. The membranous labyrinth consists of structures called the semicircular canals and otoliths which function to provide feedback for angular acceleration and linear acceleration of the head respectively. These structures provide sensory input through visual-vestibular proprioception which sends this information towards our central processing (brain) to then turn that feedback into a motor input through eye movements or our posture. Therefore, the vestibular system contributes and is responsible for eye movement.
Thus, to appropriately assess if an individual has a vestibular disorder, we can assess their Vestibular Ocular reflex (VOR). VOR allows for the stability of our gaze or vision with concurrent head movements. A normal VOR for a healthy individual is measured to be approximately 14ms. An indicator for poor gaze stability is a blurry vision when turning the head very quickly. However, a more accurate indicator is looking at VOR gain, which is the ratio of eye velocity and head velocity. Normal VOR gain is a ratio of 1.0, where the eyes move at equal speed with the opposite direction of head movement. If VOR gain is less than 0.98, then individuals will have a blurry vision as mentioned previously.
Individuals with chronic whiplash-associated disorder will likely have dizziness and/or vestibular issues as well. We often see that these individuals will stop moving their necks due to increasing dizziness that is experienced which leads to neck pain and stiffness.
Vestibular function can be assessed through:
1. Oculomotor Testing
➢ Smooth pursuits: slow-moving target on fovea
➢ Saccades: horizontal/vertical tracking
➢ If Nystagmus is present
2. VOR testing
➢ Head thrust test
➢ VOR horizontal/vertical
3. Balance and Gait
➢ The vestibular system plays an important role in our balance in helping to provide feedback for postural control
➢ We can take a look at postural control strategies through the ankle, hip, and stepping.
VOR Gain can be trained, where the CNS can change the sensitivity of the VOR. In this case, we would then utilize exercises to help adapt and improve gaze stability. An effective and simple exercise that Sarah presented to us is the Gaze Stabilization Exercise, which can help to improve gaze stability and VOR gain!
1. Gaze Stabilization Exercise (GSE)
– Goal of this exercise is to improve VOR gain
– Place an X on the wall
– Focus gaze or look at a target while performing head movements.
– A retinal slip occurs, which is an error signal that indicates movement of the image on the retina.
– In this exercise, we are attempting to reduce the error signal and sharpen up the image that is focused on!
This is an exercise that can be introduced very early on in an individual’s treatment plan to improve vestibular function, and with improvements, there are many different ways to progress exercises. We’d like to thank Sarah Lamb for Catalyst Kinetics for presenting in this in-service! If you’re someone who is currently suffering from very similar symptoms after a concussion or motor vehicle accident, I would highly suggest seeing her at Catalyst Kinetics!