Balance is a difficult concept to define. Some people seem to have a natural sense of their own body in space, others are chronically tripping over thin air and running into furniture. There are several different systems in the body that must work together cooperatively to maintain normal balance. These chiefly include the vestibular system, the visual system, the brain/brain stem, and the muscles and joints of our body. Each of these play a different role in the coordination of balance.

Vestibular system:
The vestibular system itself has multiple components that contribute to the sense of our position in space and the movement of the head in relation to the body. These include the semicircular canals and the organs that reside within our inner ear. The semicircular canals include three different structures that are oriented in three different planes, anteriorly, horizontally, and posteriorly. These are paired between the left and right side in such a way that both sides will provide the same information to the brain no matter the position that the head is in.

Next to the semicircular canals are the utricle and saccule. These sensory organs also help to provide information on the position of our head in space, but are more interested in acceleration both vertically and horizontally. Inside these organs are small crystals or otoliths that are embedded in the cellular membranes. Since these otoliths are a bit denser than the surrounding tissues and fluids, they are acted on by gravity more powerfully. When our head moves quickly or changes speed in general, these pressures in the utricle and saccule create electrical signals for the brain to interpret and coordinate. 

Visual system :
We rely on our vision a great deal when it comes to orienting ourselves in space and with our environment. The eyes provide a wealth of information about where we are, how we are moving, and allows us to keep track of all of the elements in an ever-changing environment. The visual system has a very close relationship to the vestibular system and the brain/brain stem. In fact, there are a series of reflexes that exist within the brain that allow our eyes to hold steady in difficult circumstances, such as reading in a bouncing car, or being able to follow objects even as we change the orientation of our head such as watching a plane fly overhead. These reflexes rely on the ability of the brain and vestibular system to agree very closely on the position of the head and the necessary eye movement to keep everything in focus.

If there are any discrepancies in this communication it can lead to a feeling of slowness, eye fatigue, and accompanying dizziness and disequilibrium. There is a constant rechecking going on that makes sure that what the eyes are seeing and the vestibular system are reporting match up. What this means is that any compromise to vision or even changes in lighting can affect this communication and relationship.

Muscle and Joints:
The muscular system and proprioception are another key component of balance. The feet act as our contact point to the environment when we are standing or walking. The feet themselves are quite sensitive and good at measuring both pressure and force in a fine-tuned manner. I like to think of it as the steering wheel on the highway, it never holds perfectly still even when the road is straight and the constant adjustments and small twitches are what keeps everything in place in a dynamic fashion.

The information from the feet and ankles is sent to the brain to provide a sense of how our body is oriented. When walking on an incline or a decline this can get more complicated, with more muscle activity and more information being sent to the brain. If this information conflicts with the information from the vestibular or visual systems there can be confusion in the processing in the brain and a lack of ability to adapt to the environment (such as missing a step or stumbling/staggering).
All of these fine-tuned movements and measurements happening in the body allow for a number of places where things can break down. Sometimes, this system alone can lead to balance difficulties as inaccurate information from the feet, ankles, joints, and muscles can lead the brain to make poor decisions based on faulty information. Even in people who are experiencing primarily vestibular dysfunction it is often necessary to train the muscles of the lower extremities to develop control, strength, and power. The strength and power are often overlooked, particularly in an older population, but it is vital that the muscles of the foot and ankle be able to make the adjustments needed to maintain balance.

What can happen in some situations is that the brain will recognize an adjustment needs to be made, perhaps in a more challenging environment, but the ankles and feet are not powerful enough to make the necessary correction. This can lead to stumble, stagger, or fall, depending on the situation. Beyond the feet and legs themselves there is also the consideration of the core musculature that holds our spine and hips stable while moving or statically positioned. These muscles and the general control of this area from a proprioceptive perspective can greatly affect the control of our bodies and provide other strategies for maintaining balance outside of the ankle. While the ankle is the first line of defence for the average challenge to our balance, the hips and lower back can create changes in the center of gravity.

In an ideal situation, a small challenge to our balance would rely largely on the ankles and their respective muscles to adjust. However, if the challenge is large or fast, the hips can shift to absorb some of the force and to significantly alter the center of gravity. If the movement of the hips themselves is not enough, leaning the trunk/torso by utilizing the core musculature can also be implemented to regain or maintain equilibrium.

All of this is happening in a fraction of a second and is typically coordinated by the brain without much conscious effort. That being said, it is possible to train these responses and these systems. Much like any skill, progressive practice and repetition with guidance from a skilled practitioner can typically provide improvement in strategies and functional outcomes.

~Trent, PT

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References 

• Vestibular Rehabilitation: 4th Edition. Herdman, Susan. Clendaniel, Richard. ISBN 9780803640818. F.A. Davis. July 2014. 
• Current concepts and future approaches to vestibular rehabilitation. Tjernstrom, F., Zur, O., Jahn, K. J Neurol 2016. DOI 10.1007/s00415-015-7914-1. 
• Effects of balance training on balance performance in healthy older adults: a systematic review and meta-analysis. Lesinski M., et al. Sports Med 2015. DOI 10.1007/s40279-015-0375-y.

Tinnitus is defined as the perception of sound without the accompanying external stimulus.  
Tinnitus, or ringing in the ears, affects a significant amount of the population at one time or another in their lives. While it is normal for someone to experience intermittent episodes of buzzing, ringing, or tonal sounds in the ear from time to time, some people experience a condition which is much more persistent and sometimes more bothersome. Prevalence is estimated between 5-42% of the population.  

The condition itself does not have one root cause or pathology associated with it. It can be caused by noise trauma, physical trauma, disease, aging, and as a side-effect of some medications. A number of different structures and conditions can contribute to the presentation and the symptoms that an individual experiences. This can include cardiovascular, neurological, mechanical, and inflammatory disease states. These factors will produce a sensitivity in the nervous system, leading to changes in the brain that can produce the phantom sound or make it increasingly difficult to shift our attention elsewhere.  

From a cardiovascular perspective, an increase in blood pressure can sometimes result in the ability to hear a thudding or pounding, drum-beat like sound. This can occur unilaterally or bilaterally. This can also be the result of inappropriate formation of small blood vessels in the inner ear and surrounding tissues which does not allow blood to flow through them smoothly in all situations. Anything that is of a vascular nature will require assessment and investigations as recommended by the appropriate physician and/or specialist and is outside the scope of physical therapy.  

From an inflammatory basis, a number of structures in the face, head, and ear can contribute to the perception of sound if they become irritated or sensitive. This include various nerves, the sinuses, eustachian tubes, and even the middle ear bones that conduct sound to the eardrum. The eardrum itself can be a source of irritation if it becomes inflamed or scarred as well. The treatment for this typically is medical in nature to try and reduce swelling/inflammation in the specific tissues.
 
The neurological mechanism is the most common pathway that relates to idiopathic tinnitus. Idiopathic referring to an onset of symptoms with no known injury or mechanism. This can be due to sensitization of the peripheral nervous system, central nervous system, or a combination of the two. This is typically treated through a combination of medication, education, and stress-reduction strategies.  

Mechanically, the upper cervical spine and jaw joints can contribute to a presentation of tinnitus in some cases through their connection into a cluster of nerves referred to as the trigeminocervical complex. Since the trigeminal nerve has connections to the other cranial nerves, overwhelming stimulus of these pathways can contribute to the intensity and frequency of symptom presentation. On the bright side, appropriate mechanical treatment and education surrounding these tissues can sometimes provide improvement in the tinnitus symptoms that are experienced. Not everyone has a mechanical presentation, but since treatment and therapy are non-invasive, it can be worthwhile to consider assessment by a trained healthcare practitioner.  

Another useful avenue of assessment for those suffering from tinnitus is a comprehensive hearing assessment through an Audiologist. This will assist with understanding the unique features of a patient’s presentation and help other practitioners determine an appropriate course of action. Audiologists also have the ability to treat some aspects of tinnitus with assistive devices that can create white noise, amplify normal hearing, and try to retrain the brain/nervous system to ignore the tinnitus itself.  

One of the most important things to note regarding tinnitus is that the amount of distress or the perceived volume of the sound does not relate to the severity of the condition. Louder tinnitus does not mean that someone is at greater risk of harm or injury/disease.  

~ Trent, PT

 References: 
Somatosensory tinnitus: Current evidence and future perspectives. Ralli, M. et al. Journal of International Medical Research. 2017.  

Maladaptive plasticity in tinnitus - triggers, mechanisms and treatment. Shore, S., Roberts, L., Langguth B. Nat Rev Neurol. 2016. 
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Current insights in noise-induced hearing loss: a literature review of the underlying mechanism, pathophysiology, asymmetry, and management options. Le, T., Straatman, L., Lea, J., Westerberg, B. Journal of Otolaryngology - Head & Neck Surgery. 2017.
 

The semicircular canals are a series of what are essentially tubes that exist in pairs on either side of our skull. We have one oriented towards the front, the side, and back of our skull that provide information to the brain on the position and movement of our head through space. Each canal is paired to the opposite one on the other side of our head and they are a highly coordinated system that can detect very small changes in position and posture. Inside the canal are specialized sensory cells and nervous system tissue that reside within the fluid-filled canal. The fluid inside the canal is slightly heavier than water and will slosh back and forth depending on how the head is positioned and how it moves. The pressure change from the fluid moving will stimulate the cells in the canal and produce an electrical signal that our brain can interpret as movement. It is important that both sets of canals provide the brain with the same information and at the same time to avoid confusion.
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BPPV is thought to occur when a small crystal (otoconia) or clump of cellular debris (the body’s own tissues) ends up in a part of our semicircular canals where it does not belong. The otoconia are typically stored in small organs called the utricle/saccule that reside in our inner ear. These organs attach to the ends of our semicircular canals and it is possible for small objects to pass between these areas. The crystals that normally reside inside our ear organs are used by our body to send information about gravity or the movement of our body through space in very specific directions to our brain. They are denser and heavier than the surrounding tissues which allows them to tell the brain what is changing between the relationship of our body and the environment. The current hypothesis is that these crystals can sometimes be dislodged and inappropriately move into the semicircular canals. There is some evidence to suggest that a clump of cells from our own body can sometimes form an object big enough and dense enough to create the same effect.

A typical presentation will be of an individual who reports episodes of dizziness or the sensation that the room is spinning (vertigo) when they position themselves or their head in a certain way. It may be that it is always when they roll over in bed, or always when they look up at a particular cupboard in their kitchen. The vertigo will sometimes last for only a minute or two, but in rare cases will continue until the position is changed. People will usually interpret this as a feeling that the room is spinning and can be associated with nausea, headache, and pain in the neck and upper shoulders. Many people will learn how to avoid symptom creating positions and some can go days at a time without an episode if they restrict their activity and movement. However, avoiding symptoms can promote stiffness of the neck and upper portion of the body and lead to secondary issues in the muscles and joints of these areas. It is recommended to seek assessment from a physiotherapist who understands BPPV and the various treatment options that exist.
In some cases, BPPV will resolve spontaneously. The body has the capacity to reabsorb the otoconia or the clump of cells and things will return to normal once the crystal is gone. On the other hand, sometimes people will experience episodic or constant symptoms that can last for months or years. Even after successful treatment there is the chance that the condition will reoccur, but this can typically be resolved with the appropriate treatment.
Treatment for BPPV typically consists of the following:
Canalith repositioning maneuvers - Special positions and movements that a trained therapist can guide a patient through in an effort to relocate or dislodge a misplaced crystal or clump of cellular debris.
Exercise instruction in self-treatment and management strategies - Including self-applied movements for BPPV, balance and gait exercises, or stretching and strengthening exercises for the neck and jaw.
Education regarding the condition, the treatment, and further strategies for returning to regular activity.
Biomechanical treatment of the neck and/or jaw as required - Including hands-on therapy for the joints and muscle tissues.
The first interaction with a therapist will include a detailed assessment. It is important to understand the cause of the disorder as different kinds of treatment and therapy are not indicated for all types of dizziness. The therapist will perform a mechanical examination that can include the neck and jaw, as well as a specialized assessment of the nervous system, walking patterns, balance, and positional tests for the dizziness/vertigo. If BPPV is the diagnosis, the first treatment can often be provided during the initial assessment. Depending on the person's personal situation, exercises can sometimes be prescribed for home use to assist with recovery in between sessions with the therapist. However, as dizziness and compromised balance can be a risk factor for falls and injury, not everyone is a candidate for home exercise programming at first.
- Trent, PT
References
​·         Clinical Practice Guideline: Benign Paroxysmal Positional Vertigo (Update). Bhattacharyaa, N., et al. Otolaryngology - Head and Neck Surgery. 2017. Vol. 156(3s) S1-S47.
·         Treatment of benign paroxysmal positional vertigo. A clinical Review. Perez-Vazquez, P., Franco-Gutierrez, V. Journal of Otology. 2017. Vol. 12 165-173.
·         Vestibular rehabilitation in benign paroxysmal positional vertigo: Reality of fiction? Bressi, F. et al. International Journal of Immunopathology and Pharmacology. 2017. Vol. 30(2) 113-122.