Week 6 (parts 1 and 2)

Question 1

part 1

Answer 1

cranial nerves

Question 2

what are cranial nerves

Answer 2

 Where are they?
 How many are there?
 Are they part of the CNS or PNS?
 Do they have a motor, sensory or autonomic function?
 How important are they?

Question 3

what is the 1st Olfactory nerve

Answer 3

smell:
 This is the first cranial nerve and exits from the forebrain.
 Its function is that of the sense of smell

Question 4

what is the 2nd optic nerve

Answer 4

SIGHT:
 This is the second cranial nerve and also exits from the forebrain.
 Its function is that of sight

Question 5

what is the third Oculomotor nerve

Answer 5

EYE MOVEMENT:
 This is the third cranial nerve and exits from the midbrain.
 Its function is the majority of eye movements, pupillary light reflex and eye lid opening.

Question 6

what is the 4th Trochlear nerve

Answer 6

EYE MOVEMENT:
 Fourth cranial nerve that exits from the midbrain
 Its function is with eye movement.
 Specifically to move the eye downwards and inward

Question 7

what is the 5th Trigeminal nerve

Answer 7

FACIAL SENSATION:
 The fifth cranial nerve originates from the pons.
 Its function has two components, sensation of the face
 Also supplies the muscles of mastication

Question 8

what is the 6th Abducens nerve

Answer 8

EYE MOVEMENT:
 The sixth cranial nerve exits from the pons
 Its primary function is that of abducting the eye

Question 9

what is the 7th Facial Nerve

Answer 9

FACIAL MOVEMENT:
 The seventh cranial nerve exits from the pons
 The primary function of this nerve is movement of the face
 It is also linked to sensation of taste

Question 10

what is the 8th Vestibulocochlear nerve

Answer 10

HEARING AND BALANCE:
 The eighth cranial nerve exits from the medulla
 The vestibular component assists with detecting changes in body position against gravity.
 The Cochlear components is linked to hearing

Question 11

what is the 9th Glossopharyngeal nerve

Answer 11

ORAL SENSATION, TASTE, SALIVATION:
 The ninth cranial nerve exits the medulla
 Its primary function is that of sensation to the back of the tongue, pharynx and middle ear.
 It is linked to the gag reflex

Question 12

what is the 10th Vagus nerve

Answer 12

GAG, SWALLOWING, CARDIAC:
 It exits from the medulla
 It has a sensory input to the pharynx and larynx
 It has a motor input to the throat and soft palate
 It is also linked to the heart and abdominal organs

Question 13

what is the 11th Accessory nerve

Answer 13

SHOULDER ELEVATION, HEAD TURNING:
 The eleventh cranial exits from the medulla
 It is purely motor in function.
 It innervates sternocleidomastoid and trapezius muscles.

Question 14

what is the 12th Hypoglossal nerve

Answer 14

TONGUE MOVEMENT:
 The last / twelfth cranial nerve exits the medulla
 It is motor in function and innervates the tongue.

Question 15

what are some basic cranial nerve assessment tips

Answer 15

• Look at eye movement
• Look at pupil size
• Facial sensation
• Facial movement
• Tongue Movements
• Listen to voice
• Check cough

Question 16

Part 2

Answer 16

anatomy of the spinal cord and spinal tracts

Question 17

facts about the spinal cord

Answer 17

• Part of the CNS
• Long column of afferent (ascending) and efferent (descending) nerves.
• Interneurones – small nerves linking other nerves
• Information enters and exits the spinal cord via spinal nerves
• The spinal cord is shorter than the spinal column
• The bundle of spinal nerves that descend inside the spinal column are called the cauda equina

Question 18

how are the vertebrae structured

Answer 18

c1-5 (cervical spine)
T1-12 (Thoracic spine)
L1-5 (Lumbar spine)
S1-5 (Sacrum)

Question 19

how are nerves structured

Answer 19

• Part of the CNS
• Long column of afferent (ascending) and efferent (descending) nerves.
• Interneurones – small nerves linking other nerves
• Information enters and exits the spinal cord via spinal nerves
• The spinal cord is shorter than the spinal column
• The bundle of spinal nerves that descend inside the spinal column are called the cauda equina

Question 20

how is the Cons and Cauda Equina structured

Answer 20

• The conus medullaris is the terminal end of the spinal cord, which typically occurs at the L1 vertebral level in the average adult
• The cauda equina is a group of nerves and nerve roots coming from distal end of the spinal cord, typically levels L1-L5
• Contains axons of nerves that give both motor and sensory innervation to the legs, bladder, anus, and perineum.
• The “Horses Tail”

Question 21

what are Dermatomes

Answer 21

• Dermatomes - The area of skin innervated by nerves related to a particular segment of the spinal cord

Question 22

what are Myotomes

Answer 22

• Myotomes - Muscles that are innervated by nerves related to a particular segment of the spinal cord

Question 23

what areas of the spine are innervated by what areas of the spine

Answer 23

Cervical (C1-5) - lower head and arms
Thoracic (T1-12) - Thoracic region and cage
Lumbar (L1-5) - hips and front part of legs
Sacral (S1-5) - back part of legs

• Be aware that dermatomes and myotomes apply to the spinal nerves (peripheral) and spinal cord and do not relate to the anatomy of the brain. For instance, with a spinal nerve or spinal cord injury the sensory loss will be dermatomal – the same is true for myotomes. But this does not apply to sensory loss due to brain injury

Question 24

what is Gray and white matter

Answer 24

• A single neuron is too small to see
• A collection of neuron cell bodies appear gray
• Areas of the central nervous system that are a large collection of cell bodies are called gray matter
• Some neuron processes are wrapped in insulating layers that are white so areas of the central nervous system that are a large collection of neuron processes are called white matter

Question 25

what is the Dorsal root

Answer 25

Dorsal Root - Afferent nerves that come into the spinal cord are bundled at the back in the dorsal roots The cell bodies of the dorsal root are outside the spinal cord in the dorsal root ganglia

Question 26

what is the Ventral root

Answer 26

Ventral Root - Efferent nerves leaving the spinal cord are bundled together at the front in the ventral root

Question 27

what is the ascending spinal tract system

Answer 27

* Sensory information ascends from the spinal cord to the brain via specific pathways: * Anterolateral tract * Dorsal columns (from body to brain)

Question 28

where does the descending pathway go from and to

Answer 28

from brain to spinal cord

Question 29

what is the Anterolateral Tract pathway

Answer 29

* Route for pain and temperature information * Sensory receptors: * Thermoreceptors in the skin stimulated by heat or cold * Nociceptors in skin, muscle, joints and viscera stimulated by noxious stimuli * Ascend via peripheral nerves to dorsal horn of spinal cord * Ascend spinal cord via: * Spinothalamic tract * Spinoreticular tract

Question 30

what is the spinothalamic tract

Answer 30

* Decussates (crosses) in the spinal cord and ascends to the thalamus in the brain * Relays information to the somatosensory areas of the cortex

Question 31

what is the Spinoreticular Tract

Answer 31

* Decussates (crosses) in the spinal cord and ascends to the reticular formation of pons in the brainstem * Relays information to the Thalamus, and subsequently to somatosensory areas of the cortex

Question 32

what happens when you damage the ascending systems

Answer 32

* If you damage the spinothalamic or spinoreticular tract at any point on their journey from the periphery to the spinal cord to the brain: * Present with an inability to feel pain or high temperature – this could be throughout the body depending on the site of the injury * Can be caused by any pathology of the CNS including MS, stroke, spinal cord injury, brain injury and others.

Question 33

what is the route of the dorsal columns

Answer 33

* Route for proprioceptive and discriminatory touch information * Sensory receptors * Ascend via peripheral nerves to dorsal horn of spinal cord * Ascend spinal cord via: * Medial lemniscus (touch, pressure and vibration, conscious proprioception) * Spinocerebellar tract (unconscious proprioception)

Question 34

what is the medial lemniscus

Answer 34

* Decussates in the medulla and ascends to the thalamus * Relays information to the somatosensory areas of the cortex

Question 36

what is the spinocerebellar tract

Answer 36

* Part decussates in the spinal cord and another part does not decussate * Ascends through the brainstem and relays information to the cerebellum

Question 37

what happens when you damage the ascending systems

Answer 37

* If you damage the spinocerebellar tract or the medial lemnisus at any point on their journey from the periphery to the spinal cord to the brain: * Present with an decreased, altered or absent sensation (to touch) as well as reduced proprioception. * Would present with uncontrolled movement and very prone to injury * Can be caused by any pathology of the CNS including MS, stroke, spinal cord injury, brain injury and others.

Question 38

what is the function of the descending tract

Answer 38

* Descending systems send motor information from the brain to the periphery * Medial or postural systems * Lateral or movement systems * Terminate at the motor end plate and synapse with muscle (you were told about the motor end plate when you did the structure of muscle!)

Question 39

what are the medial (postural) pathways

Answer 39

* These systems maintain joint integrity and take anticipatory actions: * Vestibulospinal tracts (medial and lateral) * Ventral corticospinal tract * Medial reticulospinal tract * Tectospinal tract * Work with type I and II a muscle fibres

Question 40

what is the vestibulospinal tract

Answer 40

* Arises in the brain stem vestibular nuclei and descend via spinal cord * Medial tract is bilateral and activates neck muscles * Lateral tract is ipsilateral (does not cross) and extends trunk and limbs * Maintains upright posture

Question 41

what is the Reticulospinal tract

Answer 41

* Arises in the reticular formation of the brain stem * Medial tract is ipsilateral and lateral tract is bilateral * Maintains posture and regulates tone * Involved in complex and bilateral movement

Question 42

what is the tectospinal tract

Answer 42

* Arises in superior colliculus of the brain stem * Decussates at origin * Co-ordinates head and eye movement

Question 43

what happens if you damage the descending system

Answer 43

* If you damage the medial or postural tracts at any point on their journey from the brain via the spinal cord to the muscles: * Loss of righting reactions (hip/ankle/stepping) and anticipatory postural adjustments * Forward slump posture * Collide with objects * Unable to reach * Decreased ability to walk * Can grasp and release and move single digits and flex and extend elbow * Can be caused by any pathology of the CNS including MS, stroke, spinal cord injury, brain injury and others. More prevalent with injury to brainstem and posterior part of the brain

Question 44

what is the descending lateral pathway

Answer 44

* Descend from brain to periphery and are involved in transitional, long lever movement * Lateral Reticulospinal tract * Dorsal Corticospinal tract * Rubro spinal tract * Work with type II b muscle fibres

Question 45

what is the Rubrospinal tract

Answer 45

* Arises in the Red Nucleus of the brain stem * Contralateral system – decussates in midbrain * Activates distal and flexor muscles

Question 46

what is the Corticospinal Tract

Answer 46

* Arise in the cortex * Medial tract is ipsilateral and innervates proximal muscles * Lateral tract decussates at the bottom of the brain stem and innervates limb muscles * Vital to hand dexterity

Question 47

what happens if you damage the descending systems

Answer 47

* If you damage the lateral or movement tracts at any point on their journey from the brain via the spinal cord to the muscles: * Normal righting reactions and anticipatory postural adjustments * Posture is normal * May be able to walk (of a fashion!) * Arms hand limply * No discrete distal movement * Unable to grasp * Can be caused by any pathology of the CNS including MS, stroke, spinal cord injury, brain injury and others.

Question 48

spinal tract system summary

Answer 48

* There are other ascending and descending systems and we have only discussed the major functions * All these systems do NOT work in isolation they all talk to each other and support or quieten each other and talk to different bits of the brain to give us a fully integrated nervous system * Also it is unlikely that injury or disease will affect one of the tracts in isolation so it is common to present with difficulty in multiple ascending and multiple descending systems

Question 49

Part 3

Answer 49

Training of the upper limb

Question 50

what is movement analysis

Answer 50

* The systematic study of human movement * We need to be able to study and recognise normal to observe and highlight deviations that are due to neurological conditions * If we understand and can reproduce movement patterns, then we can use these as part of our rehabilitation e.g. if a patient cannot sit to stand, we can prescribe them an exercise or assist them to practise sit to stand * Understanding of kinetics (motion and its causes) and kinematics (movement but not forces) assists with movement analysis. * All the treatment principles remain the same: salience, task specific, functional, intensity, reps!!

Question 54

what are the mechanics of reach to grasp

Answer 54

Object location and identification: * Visual Information * Accuracy Postural Control: * APAs * Trunk stabilisation throughout task Transport: * Hand shaping * Accelerating and decelerating Manipulation: * Stabilisation * Movement of object

Question 54

what are some training tips for neurorehabilitation

Answer 54

* Intensive * Repetitive * Constant v variable * Random v block * Massed v distributed * Task Specific * Salient* Bilateral versus Unilateral Training * Transferable * Whole v part training * Feedback * Knowledge of performance v knowledge of results

Question 55

how would you influence the reach to grasp manipulation phase

Answer 55

* Different grips for different contexts * Bilateral versus unilateral activity * Dominant versus non-dominant hand * Manipulator versus stabiliser * Consider these cases in respect of how you manipulate: * An empty water bottle * A cup with water in it * A pen * A key * Needle and thread

Question 56

what are some contextual factors that could influence the reach to grasp

Answer 56

* What if your patient has impaired vision/cognition? * Think about object location and identification * If you are reaching to grasp from a high shelf? * The distance you are required to reach? * Picking up a feather compared to picking up a brick? * What if the patient presents with ataxia (poor co-ordination) rather than weakness? * How will these impact/alter your training?