Vertigo or Dizziness

Your vestibular system uses the fluid in your inner ears to detect movement of your head. Your vestibular nerves synapse in your brainstem with motor nerves that reflexively control eye movement. This reflex moves your eyes in response to head movement to maintain focus. This is called the vestibulo-ocular reflex, and it is one of the fastest reflexes in your body at 5—10 milliseconds (5—10/1000 of a second). This enables you to maintain a steady gaze on something while your head is moving, such as walking down the street or keeping your eyes on a ball while playing sport. Vestibular system disorders result in inaccurate information in your brainstem. This results in inaccurate reflexive eye movements. As a result your eyes move to the incorrect position. Your brainstem responds by quickly moving your eyes to where they should be focused. This is a quick jerking movement called nystagmus, and it is important for diagnosis. But your eyes then drift back to their previous position. As your eyes drift back the image of the environment on your retina moves across your visual field. Your brain falsely perceives that the environment is moving when it isn’t. This is the false or distorted sense of motion responsible for vertigo. Episodes can last from seconds to several hours, depending on the cause. Head movement worsens vertigo because the brain is depending on the dysfunctional vestibular system to detect accurate head movement. Vertigo always involves your vestibular system.

Your brainstem plays an important role regulating your autonomic nervous system (ANS). This system automatically, and subconsciously manages many of your bodily functions. This includes your heart rate and digestion. Your vestibular system also communicates with your ANS. It is thought that this may be an evolutionary trait to protect us if we ingest something toxic. Vertigo signals part of your ANS in your brainstem (area postrema). It induces nausea and vomiting in case you have ingested something toxic. Vestibular dysfunction causes the brainstem to respond with nausea and vomiting, even if nothing toxic has been ingested.

The spinal cord sends sensory information to the vestibular nuclei via the cerebellum and reticular formation in the brain. The vestibular nuclei also send sensory information to the reticular formation, as well as the parabrachial nucleus. These areas then forward neural information to the sympathetic nervous system (part of the ANS) in the thoracic spinal cord, which innervates the heart, lungs and gastrointestinal tract (GIT). These signals can alter heart and lung function, as well as GIT function, initiating nausea and vomiting. A sensory mismatch between visual, vestibular and proprioceptive systems can detrimentally affect the reticular formation and parabrachial nucleus, resulting in abnormal sympathetic nervous system responses and associated cardiovascular and GIT symptoms, such as nausea and vomiting.

There are many causes, including infections, medications, low blood pressure to the brain, low blood sugar levels, and dehydration. Low blood pressure to your brain (also known as orthostatic hypotension) usually occurs when you stand up quickly from sitting or lying down. It is commonly described as lightheadedness or presyncope. Perfusion to your brain is monitored by your autonomic nervous system, medulla oblongata (part of your brainstem) and hypothalamus. These can dilate or constrict blood vessels, as well as control heart rate to increase of decrease blood pressure. As we get older these systems can sometimes slow down, resulting in a brief episode of lightheadedness or presyncope. Likewise, these symptoms can be caused by problems with your cardiovascular system. Some medications can also affect the function of these systems, such as diuretics, hypotensives (to lower blood pressure) and sedatives. Dehydration can lower your blood plasma volume, causing a drop in blood pressure. There are many types of anaemia, but all result in reduced oxygen supply to your brain. Low blood sugar can also cause these symptoms because the neurons in your brain require huge amounts of glucose to function.

A common musculoskeletal cause is cervicogenic dizziness. This is due to pain or dysfunction that impairs muscles, ligaments and joints in your neck. The highest concentration of proprioceptors exists in your ankles, because walking around on 2 feet is notoriously unstable. The 2nd highest concentration is found in your upper neck. Dizziness primarily involves a problem with proprioception. Consequently, your brain receives inaccurate proprioceptive information from these tissues in your neck. This leads to an inaccurate sense of head positioning relative to your trunk. It also causes a sensory mismatch with your visual and vestibular systems. The result is a false or distorted sense of your spatial orientation, resulting in a sense of unsteadiness or imbalance. Your brain uses proprioception to co-ordinate muscle activation sequences to maintain balance and stability, and to co-ordinate movements of your whole body. When your brain receives incorrect information from proprioceptors it can’t accurately control movement, posture and stability. Normally, milliseconds before you move, your central nervous system (CNS) stabilises your body by activating the muscles necessary to stabilise your spine and other parts of your body, such as your shoulders. Pain or dysfunction impairs your CNS’s ability to stabilise your spine or shoulders before moving. This is one of the causes of injuries that causes low back or neck pain, and shoulder injuries. So why does this cause dizziness, but not vertigo? Proprioceptive system dysfunction doesn’t cause vertigo. This is because the vestibular system is still functioning correctly and the vestibulo-ocular reflex hasn’t been affected. This is why there is no false or distorted sense of motion.

This is the most common musculoskeletal cause of dizziness. Its cause is dysfunction of your neck, right below the base of your skull. The joints, muscles and tendons in your upper neck, between your skull and the top 2 vertebrae in your neck (C1 and C2) contain specialised sensory nerves. These are proprioceptors. Your upper neck has the second highest concentration of these nerves in your body, which tells us how important proprioception of the head and neck is. Your brain uses this information to stabilise your head and the rest of your body. It also enables accurate positioning and movement of your head and body. It does this by controlling and sequencing muscle activity to maintain posture, balance and controlled accurate movements. Dysfunction of your neck results in inaccurate proprioception. This information doesn’t match vestibular and visual information. This results in a sensory mismatch, poor stabilisation and inaccurate and poorly controlled movements. You perceive this as dizziness and unsteadiness.

• neck trauma such as whiplash or sports injuries
• joint or ligament sprains in the neck
• muscle strains in the neck
• disc injury in the cervical spine
• inflammation
• degeneration or arthritis of cervical joints
• muscle fatigue or spasm
• neck pain

• worse with neck movement or prolonged postures
• usually occurs after neck pain
• associated with a tight or stiff neck that restricts movement
• associated with disorientation
• may be associated with unsteadiness
• episodes last minutes to hours, but can persist for weeks, months or even years following trauma
• recurring over days, months or years
• accompanied by cervicogenic or tension-type headache

Your practitioner will take a detailed history to assess the function of your musculoskeletal, nervous, and cardiovascular systems to identify the cause. They will perform a physical examination, including checking your blood pressure and cardiac auscultation (checking your heart function with a stethoscope) to help rule out other causes of your signs or symptoms, and may also perform orthopaedic and neurologic exams. There are no blood tests or imaging biomarkers that are useful for diagnosing dizziness, unless there is an underlying clinical suspicion of a pathological cause, such as trauma or infection, in which case you may be referred for imaging, such as x-rays, CT scans or MRI, or for blood tests. Fortunately, most causes are benign and not due to a sinister pathology. It is important that your healthcare professional accurately diagnoses the cause of your signs and symptoms because the treatments for the conditions that cause dizziness and vertigo require different treatments and rehabilitation exercises.

Medications are commonly prescribed to reduce nausea, but they can also suppress some neural functions. While this can reduce troubling symptoms, it can suppress signs and symptoms important for accurate diagnosis. Pharmaceuticals do not correct a sensory mismatch or neck dysfunction. They do not retrain proprioception or central nervous system function. They may even make diagnosis more difficult because they suppress signs and symptoms. Unfortunately, this may prolong your recovery.

Research shows that cervicogenic dizziness responds well to manual treatments and rehabilitation exercises. This improves balance, function and proprioception, and reduces pain. It is important to seek treatment early. If treatment is delayed, or signs and symptoms are suppressed with pharmaceutical drugs, treatment and rehabilitation will usually take longer because adaptations (compensations) will have started within 1 week of onset.

There are also some very effective natural medicine and nutritional treatments that can be used to treat causes such as anaemia, high or low blood pressure, to normalise blood sugar levels, and to treat infections.

You can book an appointment online or call The Headache and Neck Pain Clinic today to make an appointment.

You can also download the Dizziness and Vertigo Questionnaire here.

This is the most common cause of recurrent vertigo. It causes one-third of all vestibular disorders. It affects 2.4% of the population, or about 625,000 Australians. Women are afflicted 3.2 times more than men, usually during their 40s and 50s, whereas it can affect men at any age. It is benign, and not caused by a sinister pathology. The most common cause in people under 50 years of age is mild head trauma or whiplash.

Your vestibular system monitors the movement and position of your head in space. The semicircular canals in your inner ear form your vestibular organs. These canals contain hair-like nerves that move within fluid when you move your head. These hairs have small calcium crystal weights. These crystals can dislodge and float around in the fluid. When they bump into another hair-like nerve, that nerve will send a false signal to your brainstem about movement or position of your head. Your vestibular nerve sends an inaccurate signal of head movement to your brainstem. Your brainstem uses this information to co-ordinate accurate head and eye movements via the vestibulo-ocular reflex. This inaccurate information leads to a sensory mismatch. Information from the dysfunctional vestibular system doesn’t match the visual and proprioceptive information. The result is incorrect direction of gaze. Your brainstem attempts to correct this by redirecting your gaze. Your eyes move quickly, visible as rapid repetitive jerking movements called nystagmus. Your eyes then slowly drift back to their previous inaccurate position. Your visual system doesn’t process visual information from very rapid eye movements, but it does process visual information from slower movements. As your eyes slowly reposition the image of the environment slowly moves across your retina. This creates the image of the environment slowly moving across your visual field, like you are turning. However, your brain receives proprioceptive information that you are not moving as your vision suggests, creating a sensory mismatch. This is the false sense of movement associated with vertigo, when there is no actual movement occurring. BPPV vertigo episodes last less than 1 minute, usually less than 30 seconds. The duration of the episode is important for diagnosis. Your brain also relies on this information to control posture, balance and movement. This is why you may fall or bump into things with vertigo.

Some factors increase the risk of BPPV:

• head trauma
• advancing age
• female
• physical inactivity, such as bed rest
• low body mass index (BMI)
• ear disease or infection
• migraine
• diseases of the blood vessels that perfuse the brain (cerebrovascular disease)
• anxiety
• genetic factors
• osteoporosis and osteopenia
• diabetes mellitus type I
• low vitamin D status (research is conflicting on this)

BPPV occurs when you move your head in a specific direction. This depends on which semicircular canal is affected. It commonly affects the posterior semicircular canal. Most BPPV causes vertigo when you roll over in bed, or get up out of bed. It can also occur when you look up or bend forward. Vertigo begins 2–10 seconds after moving your head in the offending direction. The episodes lasts less than 1 minute, usually about 20 seconds. This depends on the part of the vestibular organ that is dysfunctional.

Symptoms include:

• poor balance or a sensation of tilting to the affected side
• difficulty walking
• vertigo
• visual disturbances such as blurred or jumping vision
• headache
• increased sensitivity to widespread pain
• lightheadedness
• nausea
• tinnitus

Your practitioner will take a detailed history to assess the function of your musculoskeletal, nervous, and cardiovascular systems to identify the cause. They will perform a physical examination, including checking your blood pressure and cardiac auscultation (checking your heart function with a stethoscope). They will perform a physical examination to help rule out other causes of your signs or symptoms, and also perform orthopaedic and neurologic exams. There are no blood tests that are useful for diagnosing vertigo, unless there is an underlying clinical suspicion of a pathological cause, such as anaemia or infection, in which case you may be referred for blood tests. Fortunately, most causes are benign and not due to a sinister pathology. Imaging is usually unnecessary, unless there is clinical suspicion of trauma, in which case you may be referred for an x-ray, or a CT scan to help identify problems with your semicircular canals, but these are usually not necessary because the physical exam can usually accurately identify these problems. It is important that your healthcare professional accurately diagnoses the cause of your signs and symptoms because the treatment requires different treatments and rehabilitation exercises depending on the semicircular canal that is causing the problem.

Medications are commonly prescribed to reduce nausea, but they can also suppress some neural functions, more significantly than with dizziness. While this can reduce troubling symptoms, it can suppress signs and symptoms important for accurate diagnosis. Pharmaceuticals do not correct a sensory mismatch or semicircular canal dysfunction. They do not retrain proprioception or central nervous system function. They may even make diagnosis more difficult because they suppress signs and symptoms important for diagnosis, again more significantly than with dizziness. Unfortunately, this may prolong your recovery.

Dysfunction of your vestibular system leads to a sensory mismatch. Your brain compensates by increasing your reliance on your visual or proprioceptive systems. This compensation occurs within days. Compensation and medications do not improve the function of your vestibular system. Medications are not effective at treating BPPV or compensations. They may suppress troubling symptoms such as anxiety, nausea and vomiting. Unfortunately, they inhibit the function of the vestibular system. This delays recovery and prolongs rehabilitation when used for more than a few days. This is why it is important to seek treatment as soon as possible.

Research shows that BPPV responds well to manual treatments and rehabilitation exercises. The main treatments used are gentle repositioning manoeuvres. The type of manoeuvre used depends upon the affected semicircular canal. Studies show that 80-90% of BPPV resolves with these manoeuvres. The manoeuvre aims to drain crystals away from the affected hair-like nerve receptor. This improves balance, function and proprioception. Results are usually immediate. It is important to seek treatment early. If treatment is delayed, or signs and symptoms are suppressed with pharmaceutical drugs, treatment and rehabilitation will usually take longer because adaptations (compensations) will have started within 1 week of onset.

There are also some very effective natural medicine and nutritional treatments that can be used to treat causes such as anaemia, high or low blood pressure, to normalise blood sugar levels, and to treat infections.

You can book an appointment online or call The Headache and Neck Pain Clinic today to make an appointment.

You can also download the Dizziness and Vertigo Questionnaire here.