Interventions for vestibular hypofunction in the older adult.

Purpose: 

The three major balance systems used in the human body include the vestibular, visual, and somatosensory systems.1 When one of these systems is not working properly, it can result in postural instability and balance deficits that can increase fall risk.2 The purpose of this webpage is to focus on vestibular system deficits, specifically vestibular hypofunction. This webpage provides a brief description of vestibular hypofunction followed by examples of interventions physical therapists can perform to help improve the vestibular system in symptomatic older adults.

Objectives: 

This webpage will help readers… 
 * 1) Learn more about vestibular hypofunction.
 * 2) Know appropriate examination measures to use for this condition.
 * 3) Differentiate between vestibular hypofunction and other balance disorders.
 * 4) Learn possible physical therapy interventions for patients with this condition.

'''What is vestibular hypofunction? '''

The vestibular system assists with balance and orientation with head and eye movements.3 With vestibular hypofunction, the vestibular system is not functioning properly and thus impacts the person’s ability to orient themselves in space and maintain full balance.4Symptoms of vestibular hypofunction often include dizziness, vertigo, postural instability, and gait deficits.2,4,5 The prevalence of vestibular hypofunction increases with age and can have a huge impact on quality of life.2,4 Physical therapy is commonly used to help improve vestibular function and thus it is imperative that therapists understand evidence-based interventions to help optimize their patients’ recovery.2,6

What examination measures should I use?

Here are a few common examination tools physical therapists can employ to assess for vestibular hypofunction:
 * Dynamic Visual Acuity7,8


 * Motion Sensitivity Quotient


 * Head-Shaking Induced Nystagmus Test8


 * Dix-Hallpike Test7,8


 * Dynamic Gait Index (DGI)


 * Clinical Test of Sensory Integration in Balance (CTSIB) (specifically conditions 5 and 6)9

How do I differentiate vestibular hypofunction from other sources of balance deficits?

It is important to rule out other causes of balance deficits before implementing treatment for vestibular hypofunction. Here are a few helpful hints to help distinguish vestibular hypofunction from other conditions:
 * To isolate the vestibular system, test the patient in conditions that down-regulate the use of the somatosensory and visual systems.
 * Examples: perform tests with absent/conflicting visual input or with the patient standing on a compliant surface.


 * Focus on head and eye movements, for these are the movements that are most likely to aggravate vestibular problems.
 * Rule out signs of central involvement (i.e. vertical nystagmus,8 abnormal reflexes, cerebellar findings, etc.)

What are possible PT interventions for vestibular hypofunction? * Remember: therapists should not use the same vestibular rehab plan for all patients.4Interventions should be designed for each patient’s individual needs.
 * 1) Habituation exercises2,5,6
 * 2) Focus on tasks that provoke symptoms and gradually expose the patient to these tasks while maintaining no more than a mild-moderate level of dizziness. The goal is to desensitize and ‘habituate’ the vestibular system to these movements.
 * 3) Vestibulo-Ocular Reflex exercises
 * 4) Begin by having the patient focus on a stationary object while moving their head and maintaining dizziness at mild to moderate levels. The velocity of the head movement can serve as a dizziness guide. Can progress to moving eyes and head in opposite directions while still focusing on object.
 * 5) Balance and gait training2,6
 * 6) Perform neuromuscular re-education in conditions that promote up-regulation of the vestibular system and down-regulation of the other balance systems. Can use the results of CTSIB and DGI to know what areas to focus on.
 * 7) Gait training
 * 8) Implement gait training with head turns to work on dynamic vestibular function. Can use results of DGI to know what areas of gait need improvement.
 * 9) Relaxation exercises4,6
 * 10) Anxiety and depression can be perpetuated with vestibular hypofunction and can interfere with recovery. Incorporating relaxation exercises into the patient’s plan of care can not only help improve these symptoms but also help optimize the effect of vestibular interventions.

Where can I get more information?
 * 1) https://vestibular.org/understanding-vestibular-disorder/treatment/treatment-detail-page
 * 2) https://www.american-hearing.org/disorders/balance-and-vestibular-rehabilitation-therapy/
 * 3) https://www.asha.org/Articles/Vestibular-Rehabilitation/
 * 4) https://www.brainandspine.org.uk/our-publications/our-fact-sheets/vestibular-rehabilitation-exercises/
 * 5) http://slccpta.weebly.com/vestibular-habituation.html

References:
 * 1) Balance. Physiopedia. https://www.physio-pedia.com/Balance. Accessed July 11, 2018.
 * 2) Hall CD, Herdman SJ, Whitney SL, et al. Vestibular Rehabilitation for Peripheral Vestibular Hypofunction: An Evidence-Based Clinical Practice Guideline FROM THE AMERICAN PHYSICAL THERAPY ASSOCIATION NEUROLOGY SECTION. J. Neurol. Phys. Ther. 2016;40(2):124-155. doi:10.1097/NPT.0000000000000120.
 * 3) The Human Balance System. Vestibular Disorders Association. https://vestibular.org/understanding-vestibular-disorder/human-balance-system. Published January 25, 2018. Accessed July 11, 2018.
 * 4) Lacour M, Bernard-Demanze L. Interaction between vestibular compensation mechanisms and vestibular rehabilitation therapy: 10 recommendations for optimal functional recovery. Frontiers in Neurology. 2015;5. doi:10.3389/fneur.2014.00285.
 * 5) Bayat A, Saki N. Effects of Vestibular Rehabilitation Interventions in the Elderly with Chronic Unilateral Vestibular Hypofunction. Iranian Journal of Otorhinolaryngology. 2017;29(4):183-188.
 * 6) Han BI, Song HS, Kim JS. Vestibular Rehabilitation Therapy: Review of Indications, Mechanisms, and Key Exercises. J Clin Neurol. 2011;7(4):184-196. doi:10.3988/jcn.2011.7.4.184.
 * 7) Studer M. Physical Therapy Evaluation for Dizziness and Postural Instability. American Physical Therapy Association, Section on Neurology. http://www.neuropt.org/docs/vsig-physician-fact-sheets/pt-evaluation-for-dizziness-and-postural-instability.pdf?sfvrsn=6952e8a_2. Accessed July 11, 2018.
 * 8) O'Sullivan SB, Schmitz TJ, Fulk GD. Physical Rehabilitation. 6th ed. New Delhi, India: Jaypee Brothers Medical Publishers; 2014.
 * 9) Clinical Test of Sensory Interaction on Balance. Shirley Ryan AbilityLab - Formerly RIC. https://www.sralab.org/rehabilitation-measures/clinical-test-sensory-interaction-balance-vedge. Published November 14, 2014. Accessed July 11, 2018.