Neuro conditions Flashcards
Parkinsons disease definition
A progressive movement disorder linked to the loss of dopamine within the basal ganglia
Characteristics of parkinsons
Bradykinesia, Tremor, Rigidity
Guillian-Barre Syndrome
Rare condition that affects the nerves
Causes numbness, weakness and pain
Caused by immune system mistakenly attacking/damaging the nerve by attacking schwann cells (PNS)
Pain caused by the absence of myelin
Can be triggered by infection
Treatment for Guillian-Barre syndrome
Treatments: pain killers, plasma exchange (plasmapheresis) to remove substances that attack the nerves form the blood
Stroke Types
• Ischaemic stroke: caused by blockage cutting off blood supply to the brain (most common type)
• Haemorrhagic stroke (subarachnoid and intracerebral): caused by bleeding around the brain
• Transient ischemic attack (TIA): also known as a mini-stroke. Symptoms only last a short amount of time as the blockage that stops the blood getting to the brain is temporary
Spasticity definition
Hypertonus or increased muscle tone that can occur with an upper motor neuron syndrome.
Cerebral cortex, Brainstem and Spinal Cord are three main sites of CNS lesion associated with spasticity
Neural factors leading to spasticity: Exaggeration of the stretch reflex
Exaggeration of the stretch reflex due to:
• Increased excitability of the muscle spindles- leads to inappropriate muscle activity limiting movement of joints and muscles.
• Exaggerated reflex responses occur in response to peripheral stimulation
• Abnormal processing of sensory inputs leading to excessive reflex activation
• Exaggerated response which can be dis-inhibition of the deep tendon reflexes, flexor withdrawal reflexes, active tonic reflexes and the release of primitive reflexes.
• Contributed to by the breakdown of the 1a and 2 sensory afferent inputs and alpha motor neurones.
Neural factors leading to spasticity: Supraspinal influences on the stretch reflex
• An imbalance of the supraspinal inhibitory and excitatory inputs controlling the stretch reflex
• A problem with the communication of information within the CNS down at the synapses at the spinal cord level.
Neural factors leading to spasticity: Intrinsic Hypertonia
• Muscle shortening and fibrous
• Loss of limb movement this will lead to immobility leading the muscle atrophy, decrease in weight bearing, loss of muscle mass, reduction in sarcomeres and an increase in connective tissue and fat.
• With CNS damage, this will lead to a reduction and discharge rate of firing in the voluntary motor unit within the muscle. This is due to loss of neural input along the corticospinal tract. This is the loss of the normal motor unit impulses and decrease rate of firing of neurones which leads to loss of efficiency of the muscle contraction
• Muscle shortening and fibrous
• Loss of limb movement this will lead to immobility leading the muscle atrophy, decrease in weight bearing, loss of muscle mass, reduction in sarcomeres and an increase in connective tissue and fat.
• With CNS damage, this will lead to a reduction and discharge rate of firing in the voluntary motor unit within the muscle. This is due to loss of neural input along the corticospinal tract. This is the loss of the normal motor unit impulses and decrease rate of firing of neurones which leads to loss of efficiency of the muscle contraction
Physiotherapy management of spasticity
24 hr postural management :
• Supine: legs flexed as much as possible and supported by pillow, hands together on pillow, feet supported by rolled up towels, leg supported by pillows to prevent them rolling backwards
• Sitting upright: head support near cheeks, chair slightly tilted, pillows under each arm with hands open, T-bar to aid abduction, lateral supports, rolled up towels down legs
Maintenance of soft tissue length:
• Stretch (hold for 20-30 seconds)-> viscoelastic behaviour of muscles cause short term change in muscle extensibility
• 15-30 mins for passive prolonged stretch- Longer term length change = more sustained muscle extensibility
Splinting:
TENS
Passive movements
Active movements
Modulation of tone: weight bearing movements
How Physiotherapy can modulate muscle tone
• Therapeutic movement and alteration in alignment of body parts influence tone
• Use of weight bearing, rotational movements and neuromuscular electrical stimulation e.g. TENS, electrotherapy
• Splinting and casting and manual stretching can also be used to increase muscle length
• Positioning : Alter tone at non-neural level by affecting muscle length and range- improved alignment for better movement
• Speed of stretch – slow sustained stretch is better
How Physiotherapy can help to maintain and increase muscle length
• Stretching soft tissues can improve length through 24hrs postural management
• Encouraging being active and using education
• Passive movement
• Short term manual stretch holds – 20-30 seconds (exercise) AND longer passive stretch holds 15-30 minutes (positioning/Splints/cast)
• Splinting and casting can also be used to provide a sustained stretch to help combat contracture development
Parkinsons definition
• Chronic, progressive, neurodegenerative disorder of the nervous system charcterised by tremor, bradkykinesia and postural instability
• Common disorder of the basal ganglia
Parkinsons pathology
• Pathological process from the lower brainstem (pre-clinical stage) to the midbrain (substantia nigra clinical stage) and cortex (end stage)
• There is a reduction of neuromelanin cells in the brainstem primarily dopamine neurones in the substantia nigra but also in the corpus striatum
• The Misfolding of the protein causes cell death. In Parkinson’s, the protein alpha synuclein is misfolded – leading to a lewy bodies. This inclusion means cell isn’t functioning properly so the cell dies
• People with Parkinson’s will have lost 70% of dopamine producing cells before motor signs are visible.
• The loss of dopamine causes an inability to direct and control movement (rigidity and loss of inhibition of tremor) while increasing inhibition to the thalamus (bradykinesia)
• Lack of inhibition mainly of the reticulospinal and vestibulospinal pathways results in excessive contraction of the postural muscles.
Characteristics of Parkinsons
• Rigidity: hyper-tonicity which causes stiffness or inflexibility
• Akinesis:
• Bradykinesia: slowness in movement perfomance
• Hypokinesia: decrease in amplitude for example, a lack of arm swing
• Dyskinesia: abnormal, involuntary movements
• Postural instability: loss of postural reflexes
• Tremor (rest)
Rigidity definition
bidirectional increases resistance to passive movement (not velocity dependant)
Multiple Sclerosis (MS) definition
• MS is a progressive , chronic, inflammatory (autoimmune) demyelinating disease of the CNS
• Immune system mistakenly recognises the myelin as foreign and attacks it
Pathology of MS
• Blood brain barrier breakdown-> invasion of antibodies to myelin basic protein
• T-cell mediated inflammatory response associates with secondary microglial activation
• Up regulation of inflammatory cytokines and associated oligodendrocyte damage
• Damage to myelin contributes to:
• Reduction in the speed of nerve conduction – “slowed conduction”
• The appearance of demyelinated plaque on a brain scan
• Partial re-myelination (newly differentiated oligodendrocytes) initially successful although conduction speeds are not typically restored to normal
• But repeated attacks (exacerbation) -> atonal destruction which is associated with irreversible disability = “ conduction block”.
Cerebral Palsy definition
Group of disorders that affect a person’s ability to move and maintain balance and posture
Cerebral Palsy causes
infections or other medical problems during a woman’s pregnancy
a stroke either in the womb or after birth
untreated jaundice (a yellowing of the skin and whites of eyes)
genetic disorders
Characteristics of Cerebral Palsy
developmental delays, like not reaching for toys by 4 months or sitting up by 7 months
problems with motor skills, like being unable to crawl, walk, or move arms and legs in the usual way
uncoordinated movements
muscle tone that is too tight or too loose
infant reflexes (like the palmar grasp, or “hands in fists” reflex) that stay beyond the age at which they’re usually gone
