22- Neurology 2 Flashcards
What is Chiari malformation?
Low lying cerebellar tonsils in foramen magnum
What is muscular dystrophy and what are some examples of them?
Gradual weakening and wasting of muscles
- Duchennes
- Beckers
- Myotonic dystrophy
- Facioscapulohumeral
- Oculopharyngeal
- Limb-girdle
- Emery-Dreifuss
What is the management for muscular dystrophy?
No cure, make sure highest quality of life with MDT approach
- OT
- Physio
- Wheelchair and braces
- Surgical and medical management of complications e.g spinal scoliosis, heart failure
What is Gower’s sign?
- Shows there is proximal muscle weakness
- To stand up, they get onto their hands and knees, then push their hips up and backwards like the “downward dog” yoga pose. They then shift their weight backwards and transfer their hands to their knees. Whilst keeping their legs mostly straight they walk their hands up their legs to get their upper body erect. This is because the muscles around the pelvis are not strong enough to get their upper body erect without the help of their arms.
What is the pathophysiology of Duchenne’s and Becker’s muscular dystrophy?
- X-linked recessive
- Mutation in the gene encoding dystrophin (part of the muscle cytoskeleton)
- Duchenne: protein is not expressed at all so more severe
- Becker: protein expressed but at low levels
How does Duchenne’s present?
Presentation
- Usually boys presenting at 3-5 years
- Progressive proximal muscle weakness
- Gower’s sign
- Bulky muscles as muscle replaced by fat
- Calf pseudohypetrophy
- Protruding belly
What is the prognosis with Duchenne’s?
- Wheelchair bound by teenager
- Progressive involvement of all muscles
- Life expectancy of 25-35 with death due to respiratory complications or dilated cardiomyopathy
What investigations are done to diagnose Duchenne’s or Becker’s?
- CK: raised. Do for all boys not walking by 18 months
- Genetic testing: replaced muscle biopsy
- Muscle biopsy
How can you prognosis of Duchenne’s be prolonged?
- Prednisolone (delays progression by 2 years)
- Creatine supplementation
- Gene therapy being developed
What is the presentation of Becker’s?
- Symptoms appear later around age 8
- Similar symptoms to Duchenne’s but slower progression
- Wheel chair bound late teens-20s
- No intellectual impairment
- Survive until 30-40s
What is myotonic dystrophy?
Autosomal dominant
Patients present in their 20s:
- Progressive muscle weakness
- Cataracts
- Prolonged muscle contractions (prolonged hand shake or can’t let go of door knob)
- Cardiac arrhythmias
What is spinal muscular atrophy?
- Autosomal recessive
- Progressive loss of motor neurones, leading to progressive muscular weakness
- Affects the lower motor neurones in the spinal cord so LMN signs like fasciculations, reduced muscle bulk, reduced tone, reduced power and reduced or absent reflexes.
How can you tell the difference between SMA and CP?
SMA has regression of milestones
What are the four types of SMA?
Most to least severe
SMA type 1: onset in first few months of, progressing to death within 2 years
SMA type 2: onset in first 18 months. Most never walk, but survive into adulthood. Most common
SMA type 3: onset after first year. Most walk without support, but subsequently loose that ability. Respiratory muscles less affected and life expectancy close to normal.
SMA type 4: onset in 20s. Most will retain the ability to walk short distances but require a wheelchair for mobility. Everyday tasks can lead to significant fatigue
How is spinal muscular atrophy managed?
- No cure, MDT approach
- Physiotherapy: maximise muscle strength and retain respiratory function. Splints, braces and wheelchairs used to maximise function
- Respiratory support with non-invasive ventilation
- Percutaneous endoscopic gastrostomy (PEG): if weak swallow that is unsafe
What are some causes of floppy infant?
Will present in frog leg position
- Down syndrome
- HIE
- SMA
- Prader Willi
- Cerebral palsy
- Inborn errors of metabolism
- Sepsis
What is autonomic dysreflexia?
- Occurs in patients with spinal cord injury at, or above T6
- Afferent signals, most commonly triggered by faecal impaction or urinary retention cause a sympathetic spinal reflex via thoracolumbar outflow. The usual, centrally mediated, parasympathetic response however is prevented by the cord lesion
- Unbalanced physiological response, characterised by extreme hypertension, flushing and sweating above the level of the cord lesion, agitation, and in untreated cases severe consequences of extreme hypertension and bradycardia have been reported, e.g. haemorrhagic stroke
What is microcephaly and some causes of this?
Occipital-frontal circumference < 2nd centile
What is craniosynostosis and how does this present?
Skull sutures close prematurely
- Small head circumference in relation to body
- Closure of anterior fontanelle
What is the issue with craniosynostosis?
Will lead to raised ICP causing:
- Developmental delay
- Cognitive impairment
- Vomiting
- Irritability
- Visual impairment
- Neurological symptoms and seizures