Vestibular System: What Is It & How It Leads to Dizziness?

Vestibular System: What Is It & How It Leads to Dizziness?¹

Your ears do a lot more than just hear–it is also the house of your vestibular system, or the organ that senses your position in space and helps you maintain balance. The vestibular system is made of two parts: the semicircular canals which help you sense angular (rotational) movement and the otolith organs which help you sense linear (up/down, left/right, front/back) movement. Within the semicircular canals is fluid and within the otolith organs are rocks that move when you move your head. The fluid and rocks then pull on tiny hair cells inside your ear that tell the brain which way your head is moving. Disruptions to any of these structures–semicircular canals, otolith organs, fluid, rocks, or the nerve that carries signals to the brain–lead to feelings of dizziness. Let’s explore a few of these vestibular disorders:

Benign paroxysmal positional vertigo, also known as BPPV, is a mechanical disorder where the rocks in the otolith organ come loose and enter into the semicircular canal. The extra rocks increase drag on the fluid which causes incorrect perception of head movement. This is the most common vestibular disorder that usually happens idiopathically, or without a known cause. It may also be caused by head trauma or a viral infection. In most cases, it resolves by itself, but it does have an estimated recurrence of 40-60%. Clients with BPPV often experience vertigo and nystagmus. Physical therapists can help clients achieve relief by performing maneuvers to safely shake the rocks out of the semicircular canals. 

Unilateral vestibular neuritis affects the vestibular nerve that connects the vestibular system to the brain. It typically comes after a viral infection and is most common in 30-60 year olds. Clients with this disorder constantly feel unsteady, especially when they close their eyes. Medication may be prescribed short term to ease symptoms of vertigo, but the long term treatment of unilateral vestibular neuritis is adaptation exercises that retrain the brain to correctly interpret the signals it receives. 

Meniere’s Disease is an episodic disorder that is thought to be due to too much fluid inside the ears. This may be thought to be influenced by salt intake. Clients with Meniere’s Disease will feel like their ears are full. They will also experience low frequency hearing loss and tinnitus. Episodes are spontaneous and trigger vertigo. This impairment is likely to resolve on its own over time, but there are limited treatment options due to its fluctuating tendencies. Salt restriction is the primary management strategy for Meniere’s Disease.

Concussion or traumatic brain injury (TBI) may damage parts of the vestibular system. Clients experiencing vestibular symptoms after a TBI will present with the “dangerous D’s:” diplopia (double vision), dysphagia (difficulty swallowing), dysarthria (difficulty speaking), and dysmetria (inaccurate movements). They may also have other symptoms such as photophobia, visual hypersensitivity, and audio hypersensitivity. With concussions or TBI, it is important to visit a medical doctor to address the damage to the brain. 

If you or a loved one experiences persistent or recurring dizziness, it’s important to seek assistance promptly. Consulting with a physician is crucial to rule out any underlying health issues, while a physical therapist can work with you to identify the cause of your symptoms, whether it’s related to the mentioned disorders or other potential factors, and provide targeted treatment. Don’t endure vertigo unnecessarily; take proactive steps towards recovery by consulting with a qualified physical therapist or our Live Your Life DIZZY FREE program today.

Resource:
O’Sullivan SB, Schmitz TJ: Improving Functional Outcomes in Physical Rehabilitation (3rd Ed.). F. A. Davis Company; Philadelphia, PA, 2022.