Week 11b: Disorders of Motor Function Flashcards
Which type of motor neuron lesion?
- paralysis affects movement rather than muscle
- muscle wasting is only from disuse
- spasticity of “clasping knife” type
- muscles are hypertonic
upper motor neuron lesion
Which type of motor neuron lesion?
- individual muscle or group of muscles affected
- muscle wasting is pronounced
- Flacidity
- muscles are hypotonic
lower motor neuron lesion
What is characterized by a reduction in the diameter of the muscle fibres because of a loss of protein filaments
muscle atrophy
Disuse atrophy
result of a normally innervated muscle not being used for long periods. The cells shrink but do not die
progressive deterioration of skeletal muscles because of mixed muscle cell hypertrophy, atrophy and necrosis
muscular dystrophy
Muscular dystrophy probably does not involve?
the nervous system
pseudohypertophy
when fat and connective tissue replaces the muscle fibres which increases muscle size and results in muscular weakness
growers sign is associated with?
Duchenne muscular dystrophy
signs of muscle weakness associated with Duchenne muscular dystrophy become evident…?
beginning at 2-3 years, when frequent falling occurs
respiratory muscle involvement in Duchenne muscular dystrophy
results in a weak and ineffective cough and frequent respiratory infections
a disorder of transmission at the neuromuscular junction that affects communication between the motor neuron and the innervated muscle cell
myasthenia gravis
an autoimmune disease caused by antibody mediated loss of acetylcholine receptors in the neuromuscular junction
myasthenia gravis
what is the first noticeable sign of myasthenia gravis?
weakness of the eye muscles
other possible first symptoms of myasthenia gravis?
- slurred speech
- difficult swallowing
other symptoms of myasthenia gravis that are variable in type and severity
- ptosis
- diplopia
- unstable or waddling gait
- change in facial expression
- difficulty in swallowing
- impaired speech (dysarthria)
- weakness in arms, hands, fingers, legs and neck
myasthenia crisis
worsening of muscle weakness, resulting in respiratory failure that requires intubation and mechanical ventilation
the tension test assesses for?
myasthenia gravis
what is important to have ready when administering the tension test?
atropine in case of bradycardia
treatments of myasthenia gravis
- cholinesterase inhibitors
- corticosteroids
- immunosuppressants
- plasmapheresis
- IVIg
- monoclonal antibody
- thymectomy
Characteristics of disorders of the basal ganglia
- involuntary movements
- alterations in muscle tone
- disturbances in body posture
a degenerative disorder of basal ganglia function that results in variable combinations of tremor, rigidity and bradykinesia
PKD
progressive destruction of the dopamine nigrostriatal pathway with subsequent reduction in striatal concentrations of dopamine
PKD
Dopamine deficiency in the basal ganglia associated with motor impairment
PKD
PKD results in difficulty…?
initiating and controlling movements
permanent destruction of the myelin sheath of the CNS
MS
Symptoms as MS progresses
paralysis, vision loss and diminished brain function
a progressive motor disorder affecting upper motor neurons and lower motor neurons
MS
MS disease susceptibility is linked to…?
the HLA locus on chromosome 6
first stage of MS
inflammation and small lesions due to antibody-antigen reactions
second stage of MS
due to demyelination and gliosis (scar tissue) which slows, blocks or distorts transmission impulses
a disease that is more common in males, and is a degenerative disorder that involves UMN and LMN and progressive muscle wasting
ALS
temporary loss or depression of all or most spinal reflex activity below the level of injury
spinal shock
what is a possible complication of spinal shock?
hypotension due to the lack of sympathetic tone
example of a drug that is a dopamine precursor for PKD
levodopa
example of a drug that is a dopamine receptor agonist for PKD
mirapex
example of a maoi for PKD
selegiline
example of a drug that promotes the release of dopamine for PKD
amantadine and COMT inhibitors
example of drugs that decrease the effect of Ach for PKD?
benztropine and diphenhydramine
adverse effects of sinemet
- orthostatic hypotension
- nausea, vomiting, dysphagia, anorexia, flatulence
- involuntary choreifrom movements
- headaches, anxiety, depression, agitation, insomnia
adverse effects related to anticholinergic meds
- sedation, confusion
- constipation
- nausea and vomiting
- blurred vision, dilated pupils
- dry mouth, dry skin
- urinary retention
