Neuro Week 7: Cerebelluum, Basal Ganglia

Guillian Barre syndrome

dymleination occurs bcs immune system generates antibodies against Schwann cells

Wilsons disease (Basal Ganglia disorder)

excesive copper in basal ganglia - also in liver, brain & eyes

slow twitch muscle fibers (alpha motor neurons)

smaller alpha neurons involved in posture

how to test Diadochokinesis

supination/pronation

What do alpha neurons supply?

skeletal muscles

what is the innervation ratio of motor units

# of fibers innervated by a motor unit

What is the Functional organization of Cerebellum? (3 regions )

1. Vestibulocerebellum 2. Spinocerebellum 3. Neocerebellum * ipsilateral organization (left hemisphere controls left side of body)

Types of lower motor neurons

1. alpha motor neurons - BIG (alpha) cell bodies & myleinated axons 2. gamma motor neurons - med mylelinated hoes

What are the characteristics of the neuromuscular junction?

1. endplate: excitable region that intiates AP 2. obligatory response : ACHs always released after depolarization to help maintain muscle tone

Spinal tumors types

1. extradural : outside of dura matter 2.intradural: inside dura matter

what is affected in lower motor neuron lesions

1. muscle strength 2. muscle bulk 3. muscle contraction 4. muscle tone 5. muscle stiffness 6. reflexes

myotomes

10 muscle groups tested to determine motor level of patient - 0-5 ( 5 is Fully active)

Cerebral palsy- athetoid

Basal ganglia affected - jerky, abrupt, irregular -athetoid (slow, writhing) movements)

treatment for CP- athetoid

CIMT: cast, sling splint, forced to use affected UE

Gray matter of the spinal cord

Cell bodies H shape , 3 horns 1. dorsal horn: sensory 2. ventral horn: motor 3. lateral horn: sympathetic

Cerebellar signs

DANISH Dysmetria/Dyssnergia Diadochokinesis Ataxia Astasia Abasia Nystagmus Intentional Tremors Slurred/ Scanning Speech Hypotonia

What is the finger-to-nose exam testing for? (Cerebellar signs)

Dysmetria/dysenergy - trouble controlling distance

Diadochokinesis

Inability to perform rapidly alternating movement

Poliomyelitis

a viral infection - gray matter attacked

Quadriplegia

affectation of all 4 limbs

hemiplegia

affectation of one side

motor unit consist of

alpha motor neuron and muscle fiber it innervates

myasthenia gravis

autoimmune condition affecting synapes results in fewer receptos

White matter of Spinal cord

axons 1. dorsal column 2. lateral columns 3. anterior columns

Astasia-abasia

can't stand or can't maintain against gravity

where are Upper motor neurons

cell bodies are in hgier regions of brain - synapse on lower hoes

where are Lower motor neurons

cell bodies in spinal cord/ brain stem -innervate skeletal muscle fibers

Herniated disc (spinal cord injury)

common displacement of disc in lumbar or cervical -> Compresses nerve: numbness, pain

paralysis

complete loss of voluntary movement

Function of Vestibulocerebellum?

control balance and coordinate eye-body movements

Syringomyelia

cyst/cavity formation within spinal cord - cape like distribution

hypotonia

decreased muscle tone - pendular reflex

Parkinsons disease

degenerative condition where muscle tone increases - mask fask (no automatic expressions) - freezing of gait -resting tremors

Function of Spinocerebellum

gait and balance - sensory info f

Duchenne muscular dystrophy

genetic condition of X chromosome - onset @ 5 - progressive weakness of legs and pelvis

What are the components that make up the Basal Ganglia?

has an excitatory and inhibitory pathway, imbalnce = defect

Huntingtons disease (Basal Ganglia disorder)

hereditary neurodegenrative disease - graual onset, death after 10 yrs - rigiig, jerky movements, gait & balance issues - person becomes irritable (video we watched in class)

Hyper-reflexia

hyper reflex response - tapping patellar tendon can casuse limb to react 8x

rebound phenomenon

in Ataxia - remove resistance you get flinging movement (pt can hit themself)

when does muscle tone generally increase?

in upper motor neuron injuries

how to compensate Astasia-abasia

increase base of support (stand wider)

dermatomes

key sensory points that are labeled to determin sensory levels

Ataxia

lack of coordination w/ voluntary movement

fast twich muscle fibers

large alpha motor neurons involved w quick contraction for muscles

Cerebellum

little brain - controls coordination muscle tone, motor learning, fine motor tasks

What happens in Syringomyelia

may cause segmental or longitudial signs

how is the innervation ratio determined?

more fibers innnervated for big less skilled movements - less fibers for skilled movement (eye)

signs of Guillian Barre syndrome

muscle paralysis , deep pain, can't chew, swallow, speak

What do gamma motor neurons supply?

muscle spindles

Amyotrophic lateral sclerosis (ALS)

neuropathic disease destroying motor neurons - paresis , stiffness, twitches , - loss of cranial nerves = breathing,swallowing, speaking hard

paraplegia

paralysis in trunk, legs, and pelvic

Paresis

partial loss of voluntary contraction

What happens after SCI

pt enters spinal shock - bowel and bladder ( atonic or flaccid - spasticity

post-polio

reactivation of polio virus - happens 15-30 yrs after = pain, fatigue

Wilson's disease symptoms

rigidity, resting tremors, weakness, liver function lost, - brown ring in eyes

function of neocerebellum

sensory coordination of distal limb movements - involved w cognitino

basal ganglia function ( in relation to movement)

sequence motor steps (writing), action selection, intiation/control of movement

Spinal cord injuries

severe damage to the spinal cord that impairs the function of the spinal cord

intentional tremors

tremors at the end of movement - absent @ rest

neuromusccular junction

where motor axons synapse with muscle fibers

implications of SCI (summary)

•Upper motor neuron symptoms -Paralysis/paresis -Hyperreflexia below level of injury, areflexia at level of injury -Hypertonicity: •Spasticity - hyperactive response to quick stretch •Clonus repeated stretch reflex with passive dorsiflexion of foot -Muscle stiffness/shortening/contracture •Impaired sensation •Autonomic Dysreflexia •Pressure ulcers •Sexuality issues •Bowel and bladder issues •Psychosocial implications