NURS 203: Unit 4 - Neurological System: Motor Response (Lab 4 Review)

Central Nervous System (CNS)

The portion of the nervous system that contains the brain and spinal cord cord

Peripheral Nervous System (PNS)

The portion of the nervous system that contains both cranial and spinal nerves

Amount of Cranial Nerve Pairs

12

White Matter

Myelinated axons (Ex. Inner of brain, and outer of spinal cord)

Grey Matter

Unmyelinated axons (Ex. Soma, dendrites, neuroglia, outer part of brain and inner part of spinal cord)

Amount of Hemispheres in the Brain

2

4 Lobes of Each Hemisphere in the Brain

- Frontal

- Parietal

- Occipital

- Temporal

Frontal Lobe

Lobe of the brain concerned with personality, behaviour, emotions, and intellectual function

Parietal Lobe

Lobe of the brain responsible for sensation

Occipital Lobe

Lobe of the brain that acts as the primary visual receptor centre

Temporal Lobe

Lobe of the brain located behind the ear and contains the primary auditory reception centre

Cerebrum

Largest part of the brain; responsible for voluntary muscular activity, vision, speech, taste, hearing, thought, and memory

Cerebral Cortex

The cerebrum's outer layer of nerve cell bodies; this layer looks like "grey matter"

Basal Ganglia

Part of the brain that controls automatic associated movements of the body (Ex. Alternating swinging of arms and legs)

Thalamus

Part of the brain that acts as the main relay station for the nervous system

Hypothalamus

Part of the brain that regulates hormones, temperature, apetite, pleasure, pain, rage, sleep/wake cycle, and emotional status

Cerebellum

Part of the brain that is concerned with motor coordination of voluntary movements, equilibrium, and muscle tone (Ex. Posture/balance)

3 Components of the Brain Stem

- Midbrain

- Pons

- Medulla

Midbrain

Part of the brain stem that connects the spinal cord to the thalamus and hypothalamus

Pons

Enlarged area of the brain stem containing ascending and descending fibre tracts

Medulla

- Part of the brain stem that contains all ascending and descending fibre tracts connecting the brain and spinal cord

- Controls HR, breathing, vomiting, hiccupping, and sneezing

Spinal Cord

- Structure that connect the brain to the spinal nerves

- Mediates reflexes

4 Motor Pathways

- Corticospinal/Pyramidal tract

- Extrapyramidal tracts

- Cerebellar system

- Upper/lower motor neurons

Corticospinal/Pyramidal Tract

- Motor pathway that goes from motor nerve fibers - opposite side - lateral column of spinal cord - lower motor neuron in anterior horn of spinal cord

- Mediates purposeful voluntary movement (Ex. Writing)

Extrapyramidal Tracts

- Motor pathway that originates outside of the pyramidal tract

- Maintains muscle tone and control of body movement (Ex. Walking, sitting, standing, twisting)

Cerebellar System

- Motor pathway where messages are sent from the cortex to the muscles

- Coordinates movement/posture

- Subconscious process

Upper Motor Neurons (CNS)

A complex of all of the descending motor fibres that can influence or modify the lower motor neurons

Lower Motor Neurons (PNS)

The neurons that receive the signal from the upper motor neurons and transmits it to the muscles; "final common pathway"

Reflex Arcs

- Neural circuits that control reflexive behavior

- Protects the nervous system

- Involuntary

- Maintains balance/tone

4 Types of Reflexes

- Deep tendon (myotatic)

- Superficial

- Visceral (organic)

- Pathological (abnormal)

Spinal Nerves

Nerves that spread from the spinal cord and supply the rest of the body

Amount of Spinal Nerve Pairs

31

Amount of Spinal Nerve Pairs on the Cervix

8

Amount of Spinal Nerve Pairs on the Thoracic

12

Amount of Spinal Nerve Pairs on the Lumbar

5

Amount of Spinal Nerve Pairs on the Sacral

5

Amount of Spinal Nerve Pairs on the Coccygeal

1

Dermatome

A skin area that is supplied mainly from one spinal cord segment through a particular spinal nerve

C6 Dermatome

Thumb

T1 Dermatome

Axilla

T10 Dermatome

Umbilicus

L1 Dermatome

Groin

L5/S1 Dermatome

Lower back

Subjective Data to Assess for the Neurological System

- Headache

- Head injury

- Dizziness/vertigo

- Seizures

- Tremors

- Weakness

- Incoordination

- Numbeness/tingling

- Difficulty swallowing

- Difficulty speaking

- Significant history

- Environmental/occupational hazards

Equipments Needed for a Neurological Examination

- Penlight

- Tongue blade

- Cotton swab

- Cotton ball

- Tuning fork (128 Hz or 256 Hz)

- Percussion hammer

- (Possibly) familiar aromatic substances, such as peppermint, coffee, vanilla

Screening Neurological Examination

A neurological examination performed on seemingly healthy patients whose histories reveal no significant subjective findings

Complete Neurological Examination

A neurological examination performed on patients who have neurological concerns or have shown signs of neurological dysfunction

Neurological Recheck Examination

A neurological examination performed on patients who have neurological deficits that require periodic assessments

Objective Assessments for a Neurological Examination

1.) Mental status

2.) Cranial nerves

3.) Motor system

4.) Sensory system

5.) Reflexes

Motor System Assessments for a Screening Neurological Examination

- Gait/balance

- Knee flexion (hop or shallow knee bend)

Reflexes to Assess for a Screening Neurological Examination

- Biceps

- Triceps

- Patellar

- Achilles

Motor System Assessments for a Complete Neurological Examination

1.) Muscles

2.) Cerebellar function

3.) Coordinated and skilled movements

What to Assess for Muscles for a Complete Neurological Examination

- Size

- Strength

- Tone

- Involuntary movements

Muscle Tone

The normal degree of tension in voluntarily relaxed muscles

What to Assess for Cerebellar Function for a Complete Neurological Examination

- Gait

- Heel-to-heel

- Romberg test

- Foot hop

Romberg Test

A test that that assess a patient's coordination and equilibrium by making the stand straight for 20 seconds while their eyes are closed

What to Assess for Coordinated Skilled Movements for a Complete Neurological Examination

- Rapid alternating movements

- Thumb-to-finger

- Finger-to-finger

- Finger-to-nose

- Heel-to-shin

(Often used to test intoxication levels)

Reflexes to Assess for a Complete Neurological Examination

- Deep tendon

- Superficial (cutaneous)

Deep Tendon Reflexes (DTR) that you Assess for a Complete Neurological Examination

- Biceps

- Triceps

- Brachioradialis

- Quadriceps/patellar ("knee jerk)

- Achilles ("ankle jerk")

- Clonus (optional)

5 Elements that DTRs Need to Function

- Intact afferent sensory nerve

- Functional synapse in the spinal cord

- Intact efferent motor nerve

- Neuromuscular junction

- Competent muscle

DTR Testing Guidelines

- Relax the limb and partially stretch the muscle.

- Use the end of the hammer for smaller targets and the flat end for larger targets.

- Relax your hold on the hammer.

- Strike a short, snappy blow to the muscle's insertion tendon.

- Do no let the hammer rest on the tendon.

- Compare each side.

Things to do if a Person's Reflex doesn't Appear

- Encourage further relaxation

- Change the patient's position

- Increase the strength of your blows

- Have the patient do an isometric exercise on a muscle group that is somewhat away from the one being testes

Reflex Grading Scale

Grade 4+ Reflex

Very brisk, hyperactive with clonus, indicative of disease

Grade 3+ Reflex

Brisker than average, may indicate disease

Grade 2+ Reflex

Average, normal

Grade 1+ Reflex

Diminished, low normal

Grade 0 Reflex

No response

Superficial (Cutaneous) Reflexes to Asses for a Complete Neurological Examination

- Abdominal

- Cremasteric (only in men)

- Plantar

Objective Assessments for a Neurological Recheck Exam

- Vital signs

- Level of consciousness/orientation (PPT)

- Motor function

- Pupillary response

Glasgow Coma Scale (GCS)

A scale used to assess the consciousness of a patient upon physical examination, typically in patients with neurological concerns or complaints

Abnormalities in Muscle Tone

- Flaccidity

- Spasticity

- Rigidity

- Cogwheel rigidity

Flaccidity

- Decreased muscle tone

- Associated with lower motor neuron injury

Spasticity

- Increased tone (hypertonia)

- Associated with upper motor neuron injury to corticospinal motor tract

Rigidity

- Resistance to passive movement in any direction (dystonia)

- Associated with an injury to the extrapyramidal motor tracts

Cogwheel Rigidity

- A type of rigidity that lessens by degrees during passive ROM

- Associated with parkinsonism

Characteristics of Abnormal Upper Motor Neuron Findings

Characteristics of Abnormal Lower Motor Neuron Findings

Paralysis

Muscle weakness (paresis) or loss of power - hemi/para/quadriplegia

Fasciculation

When a resting muscle twitches

Tic

Twitch that is repetitive; occurs often in relation to a neurological disorder

Myoclonus (Hiccup)

Sudden rapid jerk when falling asleep

Tremor

Contraction of muscles around a joint; dissapears in sleep

Rest Tremor

Tremor that disappears with voluntary movement

Intention Tremor

Tremor that appears with voluntary movements; medications can calm it

Chorea

Purposeless movements; jerky, sudden, and increases with voluntary movements; disappears with sleep

Acthetosis

Twisting continuous movement; slow and usually involves a distal limb

Abnormal Gaits

- Spastic hemiparesis

- Cerebellar ataxia

- Parkinsonian (festinating)

- Scissors

- Steppage/footdrop

- Waddling

- Short leg

Spastic Hemiparesis

- An abnormal gait in which one side of the body is paralyzed

- Can be caused by a head trauma

Cerebellar Ataxia

- An abnormal gait in which the person has staggering, wide-based gait; difficulty with turns; uncoordinated movement

- Can be caused by alcohol, cerebellar tumour, or MS

Parkinsonian (Festinating)

- An abnormal gait in which the person hesitates to walk and has difficulty stopping suddenly

- Can be caused by parkinsonism

Scissors

- An abnormal gait in which the person's knees cross or are in contact, like holding an orange between the thighs

- Can be caused by MS

Steppage/Footdrop

- An abnormal gait in which the person lifts knee and foot high and slaps it down hard and flat to compensate for footdrop when walking up stairs

- Can be caused by weakness of tibial muscles

Waddling

- An abnormal gait in which the person's pelvis moves up and down with walking

- Can be caused by weak hips

Short Leg

- An abnormal gait in which a person has a leg length discrepancy >2.5cm

- Can be caused by a congenital dislocated hip

Cerebral Palsy

Mixed group of paralytic neuromotor disorders of infancy and childhood

Muscular Dystrophy

Chronic, progressive wasting of skeletal musculature

Hemiplegia

Paralysis of one side of the body

Parkinsonism

A defect of the extrapyramidal tracts, causing tremor, rigidity, and akinesia (inability to initiate movement)

Cerebellar

A lesion in one hemisphere produces motor abnormalities on the ipsilateral side