Dizziness, Balance and Spatial Orientation.

Benign Paroxysmal Positional Vertigo (BPPV) Repositioning maneuvers:

Can be effective 50-70% of the time with a single treatment Purpose is to move the debris so that it no longer causes inappropriate stimulation Modified Epley maneuver for canalithiasis Semont maneuver for cupulolithiasis

Benign Paroxysmal Positional Vertigo (BPPV) Cause:

Degenerative debris (otoconia) floating in posterior semicircular canal If debris sticks to cupula-makes it heavier and more responsive (cupulolithiasis) If debris floats in long arm of canal-inappropriately causes endolymph to move the cupula (canalolithiasis)

Dizziness: Evaluation Screen with a battery of tests:

Determine if there are objective hearing deficits Determine if any associated systemic or neurologic problems-look for nystagmus Determine patient's vascular, endocrine and psychologic status- especially diabetes Determine to what degree C/S may be involved Evaluate seniors for myelopathy-Gait or balance (ataxia wide based gait, spastic gait), positive Romberg sign, Hoffman's sign, Babinski's, clonus, hyperreflexic DTRs

Benign Paroxysmal Positional Vertigo (BPPV) Management: Two Main Approaches:

Habituation exercises vs otoconia repositioning maneuvers Rarely is medication or surgery considered a viable option

Cervicogenic Vertigo:

Hx of neck trauma, muscle spasm, restricted C/S ROM Pt usually describes more of a feeling of disequilibrium where they are pulled to one side vs themselves or the room spinning Negative tests for peripheral or central vertigo Theory: joint dysfunction produces reflex muscle spasm or alters input to vestibular nuclei Tx to reduce muscle spasm and restore normal C/S motion: manipulation, e-stim, HMP, myofascial therapy, traction

Dizziness: Evaluation Nystagmus- Peripheral Vertigo suggested:

Nystagmus is horizontal or horizontal rotational Decreased by visual fixation Increased with gaze toward the fast phase of nystagmus Occurring in one direction but bilateral Assoc with position change Assoc with moderate to severe vertigo

Dizziness: Evaluation Nystagmus- Central Vertigo suggested:

Nystagmus is variable in direction or vertical Unaffected by visual fixation Present with eyes open or closed Associated with constant, mild vertigo

Dizziness: Evaluation Nystagmus:

Passive-spontaneous nystagmus without head movement Active-provocative maneuvers used to elicit nystagmus Generally accompanies sensation of spinning If no vertigo, but nystagmus present think central neurologic cause-neuro consult May help to differentiate b/t central and peripheral causes

Benign Paroxysmal Positional Vertigo (BPPV) Evaluation:

Pt c/o of head positioning specific onsets of vertigo-ex. Looking to the right provokes vertigo Provoked by positioning maneuvers Hallpike maneuver: Seated pt is quickly positioned to supine position with head turned 45d to side of complaint. (+) if small latency of a few seconds before vertigo and nystagmus begin. The vertigo is severe and the nystagmus is usually horizontal-rotational to the same side. If the patient is left in this position or returned to the position several times, the vertigo fatigues

Dizziness: Management Consider referral or co-management if:

Pt has had head trauma and is demonstrating neuro signs or skull fracture suspected Prescription medication suspected as the underlying cause Dizziness is incapacitating, requiring meds during symptomatic phase If the dizziness seems to have strong psychologic component If patient appears to have cardiopulmonary issue The patient needs special audiologic testing or special imaging if considering brain tumors, cerebrovascular accidents, demyelinating diseases (MS) or extrapyramidal disorders (Parkinson's) The patient has hearing loss

Dizziness: Management Chiropractic/Naturopathic Treatment:

Pt has peripheral vertigo Peripheral vertigo can be treated with manipulation techniques, habituation exercises, other conservative approaches Refer if TX is ineffective or dizziness creates significant functional impairment

Benign Paroxysmal Positional Vertigo (BPPV):

Pt reports bouts of vertigo that occur with certain head positions Most common cause of vertigo (peripheral) Vertigo lasts for seconds to couple of minutes Position changes that precipitate attacks: neck extension, neck rotation, bending over and straightening back up, rolling over in bed

Check reflex:

Response to a release in resistance so that the contractions stop, or check, movement The check reflex depends on cerebellar input to keep increased contraction from continuing after the removal of resistance. The patient flexes the elbow against resistance from the examiner to extend the elbow. When the examiner releases the arm, the patient should be able to stop the increased contraction and keep the arm from moving. A similar response would be seen if you try to pick up a coffee mug that you believe to be full but turns out to be empty. Without checking the contraction, the mug would be thrown from the overexertion of the muscles expecting to lift a heavier object.

Benign Paroxysmal Positional Vertigo (BPPV) Habituation exercises:

Take advantage of the fatigue and adaptation responses of holding the head in the provocative position or repeatedly acquiring the provocative head position Additionally, exercises can be used to train independent eye movement and balance control

Cerebellar testing for tremor and motor commands:

The patient extends their arms in front of them and holds the position. The examiner watches for the presence of tremors that would not be present if the muscles are relaxed. By pushing down on the arms in this position, the examiner can check for the rebound response, which is when the arms are automatically brought back to the extended position. The extension of the arms is an ongoing motor process, and the tap or push on the arms presents a change in the proprioceptive feedback. The cerebellum compares the cerebral motor command with the proprioceptive feedback and adjusts the descending input to correct. The red nucleus would send an additional signal to the LMN for the arm to increase contraction momentarily to overcome the change and regain the original position.

Romberg test:

The patient stands upright with legs together - but not pressed tightly together - and with arms held forward, horizontal to the floor and palms facing upwards (some sources say arm at sides). Patients should remove their shoes for the test, and they should not be able to orient themselves to any light or sound source. A tendency to sway and fall with eyes closed in a consistent and specific direction is suggestive of a vestibular problem-sway to the side of "weakness" A tendency to sway in a multidirectional manner is suggestive of a dorsal column/proprioceptive disorder A tendency to sway and fall that is already evident with eyes open is suggestive of dizziness of cerebellar origin, but could also point to a vestibular problem

Otogenic dizziness may occur in association with:

Tinnitus Auditory impairment Pressure sensations in the ear Peripheral facial nerve palsy

Benign Paroxysmal Positional Vertigo (BPPV) Semont maneuver for cupulolithiasis:

You are seated, and the doctor turns your head so that it is halfway between looking straight ahead and looking away from the side that causes the worst vertigo. The doctor then lowers you quickly to the side that causes the worst vertigo. When your head is on the table, you are looking up at the ceiling. The doctor holds you in this position for 30 seconds. The doctor then quickly moves you to the other side of the table without stopping in the upright position. When your head is on the table, you are now looking down at the table. The doctor holds you in this position for 30 seconds. The doctor then helps you sit back up.

Cerebellar ataxia is fairly easy to observe in the office and it has at least two origins: ________________________________________________.

(1) intention tremor of the legs, giving a dysmetric gait, and (2) truncal imbalance

Balance and spatial orientation are determined by information from three components:

-positional sense through muscles and joints (proprioception) -the vestibular organ in the middle ear (vestibular system) -eyesight/eyes, what a person sees (vision or visual perception)

Causes of non-vestibular dizziness:

Cervical dysfunction, cranial trauma, ocular disturbance, cerebral sclerosis, orthostatic dysregulation, anemia, hypoglycemia, hypovitaminosis (B6, B12, Vit D), temporal lobe epilepsy, psychological disorders.

A variation of the coordination exam is the _______________________ used to assess whether drivers are under the influence of alcohol.

Field Sobriety Test (FST)

-a proprioceptive sensory nerve ending embedded among the fibers of a tendon, often near the musculotendinous junctions.

Golgi tendon organ

-it is compressed and activated by any increase of the tendon's tension, caused either by active contraction or passive stretch of the corresponding muscle.

Golgi tendon organ

__________________ is a disorder that can affect both equilibrium and hearing in a variety of ways: The patient can suffer from vertigo, a low-frequency ringing in the ears, or a loss of hearing. From patient to patient, the exact presentation of the disease can be different. Additionally, within a single patient, the symptoms and signs may change as the disease progresses. Use of the neurological exam subtests for the vestibulocochlear nerve illuminates the changes a patient may go through. The disease appears to be the result of accumulation, or over-production, of fluid (endolymph) in the inner ear, in either the vestibule or cochlea.

Meniere's Disease

Causes of central vestibular dizziness:

Multiple sclerosis, acoustic neuroma, intoxication (alcohol etc.), transient ischemic attacks (TIAs)

Causes of peripheral vestibular dizziness:

Ménière's disease, labyrinthine disease, vestibular neuronitis, benign paroxysmal positional vertigo (BPPV), herpes zoster involving the auditory nerves.

Finger-to-nose test:

Patient, with eyes open and shoulders abducted to 90 degrees, horizontally adducts shoulder and flexes elbow to touch the tip of their index/pinky finger to the tip of their nose. Pt repeats the procedure on the other side. Pt then closes their eyes and repeats the procedure. A similar test for the lower extremities has the patient touch their toe to a moving target, such as the examiner's finger.

Balance and equilibrium, as tested by the ___________ test, tie in aspects of vestibular, spinal and cerebellar processes and are important components of the neurological exam.

Romberg

The ________________ test has the patient stand still with the eyes closed. Any changes in posture would be the result of proprioceptive deficits, and the patient is able to recover when they open their eyes. If significant unidirectional sway is observed it is most likely the result of vestibular issues. If the patient has difficulty maintaining the position with eyes open and eyes closed, consider the cerebellum as a possible cause.

Romberg

-refers to the position a person adopts when they are standing still.

Station

A subtest called ______________, begins with the patient standing in a normal position to check for the placement of the feet and balance.

Station

Subtests of walking begin with having the patient walk normally for a distance away from the examiner, and then turn and return to the starting position. The examiner watches for abnormal placement of the feet and the movement of the arms relative to the movement. The patient is then asked to walk with a few different variations. _____________________ is when the patient places the heel of one foot against the toe of the other foot and walks in a straight line in that manner. Walking only on the heels or only on the toes will test additional aspects of balance.

Tandem gait

A subtest called Station:

The patient is asked to hop on one foot to assess the ability to maintain balance and posture during movement.

Unterberger stepping test:

The patient takes 50 paces on the spot, each time raising the thighs to the horizontal. The patient's arms should be held out in front, horizontal to the floor. If there are muscle tone differences referable to the labyrinthine system (e.g. labyrinthine lesion etc.), the patient gradually rotates towards the side of the lesion. Rotation of more than 40-60° is pathological (rotation towards the side of the lesion).

Finger-to-finger test:

The patient touches their finger to the examiner's finger and then to their nose, and then back to the examiner's finger, and back to the nose. The examiner moves the target finger to assess a range of movements.

Heel to Shin Test:

To test similar function in the lower extremities, the patient touches their heel to their shin near the knee and slides it down toward the ankle, and then back again, repetitively.

True or false? Dizziness of vestibular origin may be permanently present or occur episodically and may be caused by certain body positions or when changing position.

True

Focal lesions include strokes affecting the cerebellar arteries, tumors that may impinge on the cerebellum, trauma to the back of the head and neck, or MS. Alcohol intoxication or drugs such as ketamine cause ataxia, but it is often reversible. Mercury in fish can cause ataxia as well. Hereditary conditions can lead to degeneration of the cerebellum or spinal cord, as well as malformation of the brain, or the abnormal accumulation of copper seen in ______________________.

Wilson's disease

Babinsky-Weil test:

With the eyes closed, the patient takes 2-3 steps alternately forward and then backward for 10 or more times. In cases where pathology is present, there is gradual rotation to the side of the lesion.

hypotonia

a condition in which there is diminished tone of the skeletal muscles

If cerebellar ataxia is advanced, the patient has a wide-based compensatory gait, and if there is lateralized limb involvement, they tend to lean and fall toward the _____________ side.

affected

The lateral cerebellum is referred to as the cerebrocerebellum, reflecting the significant input from the cerebral cortex through the cortico-ponto-cerebellar pathway. Processing in the lateral regions target movements of the ______________________ musculature.

appendicular

A movement disorder of the cerebellum is referred to as ________.

ataxia

Deficits in cerebellar function result in ___________, or a specific kind of movement disorder.

ataxias

Another common aspect of the FST is to have the driver extend their arms out wide and touch their fingertip to their nose, usually with their eyes closed. The point of this is to remove the visual feedback for the movement and force the driver to rely just on proprioceptive information about the movement and position of their fingertip relative to their nose. With eyes open, the corrections to the movement of the arm might be so small as to be hard to see, but proprioceptive feedback is not as immediate and __________________ movements of the arm will probably be needed, particularly if the cerebellum is affected by alcohol.

broader

Sensation of imbalance or lack of coordination:

cerebellar or proprioceptive dysfunction

The patient is asked to touch each finger to their thumb, or to pat the palm of one hand on the back of the other, and then flip that hand over and alternate back-and-forth. Rapid, alternating movements are part of speech as well. A patient is asked to repeat the nonsense consonants "lah-kah-pah" to alternate movements of the tongue, lips, and palate. All of these rapid alternations require planning from the _______________________ to coordinate movement commands that control the coordination.

cerebrocerebellum

The three components for balance and spatial orientation; proprioception, vestibular system, and visual perception; integrate with the cerebellum and cerebral cortex to _________________________.

coordinate movement

The motor commands from the cerebral hemispheres travel along the _______________ pathway, which passes through the pons.

corticospinal

Info specific to cerebellum is non-conscious and travels via spinocerebellar tract, this info is then compared by cerebellum to descending info from cerebrum in ___________________________.

corticospinal tract

What may be one of the top 3 complaints following an acceleration/deceleration injury to the neck?

dizziness

What ranks among the top 3 complaints in primary care, internal medicine and ER departments?

dizziness

If the trunk alone is involved in ataxia, as in early alcoholic degeneration or with a tumor of the vermis, there is a tendency to fall to _______________________________________.

either side, forward or backward

The cerebellum is crucial for coordinated movements such as keeping balance while walking, or moving appendicular musculature on the basis of proprioceptive feedback. The cerebellum is also very sensitive to ________________, the particular type of alcohol found in beer, wine, and liquor.

ethanol

Station refers to the position a person adopts when they are standing still. The examiner would look for issues with balance, which coordinates proprioceptive, vestibular, and visual information in the cerebellum. To test the ability of a subject to maintain balance, asking them to stand or hop on one foot can be more demanding. The examiner may also push the subject to see if they can maintain balance- like the check reflex for the body. An abnormal finding in the test of station is if the ___________________________.

feet are placed far apart

The ___________________ lobe is referred to as the vestibulocerebellum because of the vestibular projection into that region.

flocculonodular

Cerebellar damage can occasionally be reflected in hypotonia. The examiner should check for abnormalities of tone by asking the patient to relax and not resist. The limbs are then moved rapidly by the examiner in several ranges. A lack of resistance or a floppiness is noticed with hypotonia. Having the patient sit with his legs swinging free may test the legs. The leg is lifted by the examiner and released. Normally the leg swings back and forth several times and then stops, arrested by inertia and the normal resting muscle tone, which is a manifestation of the sensitivity of the normal muscle stretch reflex. With cerebellar hypotonia, the leg swings ______________________________________.

freely, unchecked, like a pendulum, arrested mainly by passive limb inertia

A movement disorder of the cerebellum is referred to as ataxia. It presents as a loss of coordination in voluntary movements. Ataxia can also refer to sensory deficits that cause balance problems, primarily in proprioception and equilibrium. When the problem is observed in movement, it is ascribed to cerebellar damage. Sensory and vestibular ataxia would likely also present with problems in ________________________.

gait and station

A sensitive test for ataxia is _______________________________; this should be part of any neurologic screening examination in a patient with gait or balance complaints because it detects early cerebellar dysfunction.

heel-to-toe tandem walking

Cerebellar damage can occasionally be reflected in __________________.

hypotonia

The motor commands from the cerebral hemispheres travel along the corticospinal pathway, which passes through the pons. Collateral branches of these fibers synapse on neurons in the pons, which then project into the cerebellar cortex through the middle cerebellar peduncles. Ascending sensory feedback, entering through the _____________ cerebellar peduncles, provides information about motor performance. The cerebellar cortex compares the command to the actual performance and can adjust the descending input to compensate for any mismatch. The output from deep cerebellar nuclei projects through the superior cerebellar peduncles to initiate descending signals from the red nucleus to the spinal cord.

inferior

The ICP arises from the medulla—specifically from the ________________, which is visible as a bulge on the ventral surface of the brain stem.

inferior olive

Problems with balance, such as vertigo, and deficits in hearing may both point to problems with the ______________.

inner ear

Within the petrous region of the temporal bone is the bony ______________ of the inner ear.

labyrinth

The _____________________ are primarily concerned with planning motor functions through frontal lobe inputs that are returned through the thalamic projections back to the premotor and motor cortices.

lateral hemispheres

Two other white matter bundles connect the cerebellum to the other regions of the brain stem- superior cerebellar peduncle (SCP) is the connection of the cerebellum to the midbrain and forebrain, inferior cerebellar peduncle (ICP) is the connection to the _________________.

medulla

The motor commands from the cerebral hemispheres travel along the corticospinal pathway, which passes through the pons. Collateral branches of these fibers synapse on neurons in the pons, which then project into the cerebellar cortex through the ____________ cerebellar peduncles.

middle

Pons means "bridge", is derived from its connection to the cerebellum and refers to the thick bundle of myelinated axons that form a bulge on its ventral surface. Those fibers are axons that project from the gray matter of the pons into the contralateral cerebellar cortex. These fibers make up the ____________________________________________ and are the major physical connection of the cerebellum to the brain stem.

middle cerebellar peduncle (MCP)

Balance or hearing deficits may be the result of damage to the _____________________ ear structures.

middle or inner

Some persons with _________________ cerebellar damage may have a stronger tendency to fall backward- retropulsion and can also be seen in basal ganglia dysfunction (particularly Parkinsonism) and in frontal lobe disorders.

midline

What are the two basic regions of the cerebellum?

midline and hemisphere

-a sensory receptor in a muscle that responds to the stretching of tissue.

muscle spindle

Proprioception is gained primarily from integration of information from __________________________________.

muscle spindles, joint receptors and cutaneous mechanoreceptors

In older patients, _______________ is a common cause of sense of imbalance.

myelopathy d/t spinal stenosis

Balance and spatial orientation are maintained by an integrated ___________________________.

neuronal feedback loop

A disturbance of the organ of balance is associated with _______________, even without external irritation of the vestibular organ.

nystagmus

Though the station subtest appears to be similar to the Romberg test, the difference is that the patient's eyes are ________________________________________________.

open during station and the feet should be at approximately shoulder width

VOR achieves clear vision during head motion by moving the eye in the opposite direction at the same speed. Abnormal VOR gain (ratio of eye velocity/head velocity) causes ___________________________________ or blurring of vision.

oscillopsia (sensation that the surrounding environment is constantly in motion when it is stationary)

With frontal lobe dysfunction and Parkinsonism, the retropulsion is usually ____________ rather than active. This means that the patient has difficulty recovering from being pushed backward or from a backward-leaning position even though they may have no active or forced retropulsion at rest.

passive

The cerebellum is located in apposition to the dorsal surface of the brain stem, centered on the ________.

pons

The root cause of the ataxia may be the sensory input—either the __________________ input from the spinal cord or the equilibrium input from the vestibular system, or direct damage to the cerebellum by stroke, trauma, hereditary factors, or toxins.

proprioceptive

Sensory feedback in the form of proprioception from the spinal cord, as well as vestibular sensations from the inner ear, enters through the ICP. If you take a step and begin to slip on the floor because it is wet, the output from the cerebellum—through the SCP—can correct for that and keep you balanced and moving. The ______________ sends new motor commands to the spinal cord through the rubrospinal tract.

red nucleus

The midline regions of the cerebellum, the vermis and flocculonodular lobe, are involved in comparing visual information, equilibrium, and proprioceptive feedback to maintain balance and coordinate movements such as walking, or gait, through the descending output of the ___________.

red nucleus

When ________________________ is due to cerebellar involvement, it frequently has an involuntary tonic character, i.e., the patients actually appear to be actively pushing themselves backward. Even at rest, sitting or standing, there is a tendency to lean or fall backward.

retropulsion

Benign Paroxysmal Positional Vertigo (BPPV) Epley/Modified Epley maneuver for canalithiasis

side, follow the same steps, but turn your head in the opposite direction. Step 1: Start sitting up on a bed, with your legs flat on the bed in front of you. Turn your head 45 degrees to the left. Step 2: Lie down, keeping your head turned to the left. Wait 30 seconds. Step 3: Turn your head to the right 90 degrees, until it's facing 45 degrees to your right side. Wait 30 seconds. Step 4: Roll over onto your right side before sitting up. If performed by the doctor: maneuver entails the doctor rotating the patient's head and laying them down quickly with the patient holding onto the doctor's arm

Dizziness may be perceived as:

spinning of the room or self, motion imbalance or lack of coordination while walking, lightheadedness or sensation of almost fainting (presyncope)

Info specific to cerebellum is non-conscious and travels via __________________________, this info is then compared by cerebellum to descending info from cerebrum in corticospinal tract.

spinocerebellar tract

The ICP conveys sensory input to the cerebellum, partially from the ____________________________________, but also through fibers of the inferior olive.

spinocerebellar tract

The primary role of the cerebellum in relation to the spinal cord is through the ___________________________; it controls posture and gait with significant input from the vestibular system.

spinocerebellum

Gait can either be considered a separate part of the neurological exam or a subtest of the coordination exam that addresses walking and balance. Testing posture and gait addresses functions of the ________________________________________________ because both are part of these activities.

spinocerebellum and the vestibulocerebellum

The motor commands from the cerebral hemispheres travel along the corticospinal pathway, which passes through the pons. Collateral branches of these fibers synapse on neurons in the pons, which then project into the cerebellar cortex through the middle cerebellar peduncles. Ascending sensory feedback, entering through the inferior cerebellar peduncles, provides information about motor performance. The cerebellar cortex compares the command to the actual performance and can adjust the descending input to compensate for any mismatch. The output from deep cerebellar nuclei projects through the __________________ cerebellar peduncles to initiate descending signals from the red nucleus to the spinal cord.

superior

The SCP projects into the midbraim. The SCP is the major output of the cerebellum, divided between the red nucleus in the midbrain and the _____________, which will return cerebellar processing to the motor cortex.

thalamus

The midline of the cerebellum os composed of _____________________. The hemispheres are the lateral regions.

the vermis and the flocculonodular lobe

Dizziness of vestibular origin condition affects the structures of the vestibular apparatus: ________________________________________________.

the vestibule, semicircular canals/ducts, vestibulocochlear nerve (CN VIII), vestibular nerve nuclei in the brainstem, vestibular nerve pathways to the temporal lobe, the eyes

-involves the cranial nerves for gaze control- information from the vestibular labyrinth of the inner ear is used to generate eye movements that stabilize gaze during head movements.

the vestibulo-ocular reflex (VOR)

The subtests that address appendicular musculature, and therefore the lateral regions of the cerebellum, begin with a check for ____________.

tremor

True or false? Ataxia is often the result of exposure to exogenous substances, focal lesions, or a genetic disorder.

true

The vestibule is the portion for equilibrium, composed of the ________________________________________________.

utricle, saccule, and the three semicircular canals

The ___________ is referred to as the spinocerebellum because it primarily receives input from the dorsal columns and spinocerebellar pathways.

vermis

Walking in a straight line involves comparing the motor command from the primary motor cortex to the proprioceptive and _______________ sensory feedback, as well as following the visual guide of the white line on the side of the road. When the cerebellum is compromised by alcohol, the cerebellum cannot coordinate these movements effectively, and maintaining balance becomes difficult.

vestibular

Sensation of spinning or motion:

vestibular and central processing systems

Damage to the _________________________________________________ produces vestibular findings, including nystagmus that may be quite severe and in different directions depending on which way the patient is looking ("gaze-shifting nystagmus"). This is often more severe than symptoms due to vestibular damage since vestibulocerebellar damage is more difficult to compensate for.

vestibulocerebellum (flocculonodular lobe; archicerebellum)

The _______________ nerve carries both equilibrium and auditory sensations from the inner ear to the medulla.

vestibulocochlear (CN VIII)

The MCP is the ventral surface of the pons. The MCP is part of the cortico-ponto-cerebellar pathway that connects the cerebral cortex with the cerebellum and preferentially targets the lateral regions of the cerebellum. It includes a copy of the motor commands sent from the precentral gyrus through the corticospinal tract, arising from collateral branches that synapse in the gray matter of the pons, along with input from other regions such as the _____________________.

visual cortex

The cerebellum is an important part of motor function in the nervous system. It apparently plays a role in procedural learning, which would include motor skills such as riding a bike or throwing a football. The basis for these roles is likely to be tied into the role the cerebellum plays as a comparator for ___________________.

voluntary movement