anatomy - movement and control Flashcards
upper motor neurone lesion
hypertonicity - spasticity after a couple of days
spasticity
paralysis of movement rather than individual muscles
hopping rabbit posture
moderate muscle wasting
babinski sign
hyperreflexia
lower motor neurone lesion
paralysis of individual muscles
hypotonicity - flaccidity
muscle wasting
tendon reflexes are absent
what supplies the internal capsule?
middle cerebral artery
function of basal ganglia
initiation and termination of movement
initiation and termination of some cognitive functions - attention, memory, planning, emotions and cognition via projections to cortical and limbic systems
damage of basal ganglia
leads to spontaneous and inappropriate movement
what is the anatomy of the basal ganglia?
collection of nuclear masses in forebrain
caudate nucleus
putamen
globus pallidus
amygdala - part of limbic system
2 midbrain structures = substantia nigra and subthalamus
caudate nucleus
most superior part of basal ganglia
above and lateral to thalamus
medial to internal capsule
putamen and globus pallidus
together = lentiform nucleus
putamen and caudate nucleus
functionally related
form corpus striatum
what makes up the limbic system?
hippocampus amygdala thalamus hypothalamus their connections
what is the role of the limbic system?
initiation and termination neuroendocrine motivation mood attention planning focus concentration emotional function
what is the amygdala?
part of limbic system
where movement and cognitive/ emotional abilities are linked
substantia nigra
dopaminergic neurones to basal ganglia
pigmented dopaminergic neurones projecting to corpus striatum of basal ganglia
largest nuclei in midbrain
black due to melanin
what is ballismus?
severe chorea with thrashing motions
what is athetosis?
involuntary writhing movements of limbs and neck - twisting anf turning
pneumonic for cerebellar problems
DANISH
DANISH
Dysdiadokokinesis Ataxia Nystagmus Intention tremor Speech disturbance Hypotonia
non- corticospinal motor pathways
originate from subcortical groups of motor neurons/ nuclei
control posture and balance
control coarse movements of proximal muscles
coordinate head, neck and eye movements in response to visual stimuli/ targets
project back to cortical motor regions and circuits in the spine
what is the trunk?
body minus head and limbs
what is the torso?
the trunk
what is the back?
spine
what is the spine
starts at inferior border of skull and ends at tip of coccyx
what is the role of the spine?
- protects spinal cord and spinal nerves
- carries the superior portion of body
- allows resistance to gravity
- absorbs shocks through curves and intervertebral discs
- allows limited movement of trunk and neck
vertebra of the spine?
33 vertebrae
24 separate bones
what are the regions of the spine?
cervical thoracic lumbar sacral coccygeal
sacral spine
5 vertebrae fused together
coccygeal spine
4 vertebrae all fused together - represented with Co not C
shape of cervical spine
lordosis
shape of thoracic spine
kyphosis
shape of lumbar spine
lordosis
formation of cervical lordosis
3 months when baby lifts head
lumbar lordosis formation
10 months - 1 year when baby begins to walk
exaggerated lumbar lordosis
common in pregnant women
exaggerated thoracic kyphosis
common in elderly
what are the different types of spina bifida?
spina bifida occulta
closed spinal dysraphism
meningocele
myelomeningocele
spina bifida occulta
closed asymptomatic neural tube defect in which some of the vertebrae are not completely closed
closed spinal dysraphism
deficiency of at least 2 vertebral arches
can be covered with a lipoma
meningocele
protrusion of meninges filled with CSF through defect in skull or spine
myelomeningocele
open spinal cord
with a meningeal cyst
innervation of anterior 2/3 of tongue
hypoglossal = motor
facial = special sensory (taste)
trigeminal mandibular branch via lingual nerve = general sensory
vagus nerve = motor to palatoglossus
innervation of posterior 1/3 tongue
glossopharyngeal nerve = general and special sensory
intrinsic muscles tongue
superior longitudinal
inferior longitudinal
transverse
vertical
extrinsic muscles of tongue
hypoglossus
styloglossus
genioglossus
palatoglossus
embryological origin of the tongue
pharyngeal arches
each one has its own cranial nerve supply
locked jaw
dislocation of temporomandibular joint/ TMJ
- head of mandible moves past articular tubercle
- caused by opening mouth too wide
- physical relocation required
what are the phases of swallowing?
voluntary oral phase
involuntary pharyngeal phase
involuntary oesophageal phase
voluntary oral phase
controlled by cerebral cortex via cranial nerves
involuntary pharyngeal phase
rapid
controlled by sensory receptors and swallowing centre in medulla
triggers reflex arc
respiration is momentarily stopped
involuntary oesophageal phase
peristaltic movement
involves vagus and accessory nerves
sympathetic fibres
what cranial nerves are involved in swallowing?
trigeminal facial glossopharyngeal vagus controlled by cerebral cortex and brainstem
other controls of swallowing
common integration area
brainstem
cranial nerve nuclei
common integration area
integrates sensory information about food, size, temperature and texture from mouth, pharynx and larynx
makes decision whether to swallow and sends orders to reflex muscles of mastication which close the larynx and epiglottis
deglutition reflex arc
- sensory receptors in oropharynx send signal to deglutition centre in brainstem
- initiates motor activity mediated by cranial nerves
- effects muscle contraction to:
- elevate soft palate to close the nasopharynx
- move the epiglottis and elevate it to close off the larynx
- initiates peristalsis of pharynx and oesophagus - respiration is temporarily stopped during the pharyngeal phase
what is the role of the gag reflex?
protection of GI tract
gag reflex
- glossopharyngeal nerve – tactile sensation from posterior 2/3 tongue
- brainstem – sensory nucleus of trigeminal nerve
- brainstem – nucleus ambiguous of vagus and hypoglossal nuclei
- vagus and glossopharyngeal nerves – efferent pathway to muscles
- innervation of muscles of soft palate, pharynx, upper part of oesophagus and stylopharyngeus (innervated by glossopharyngeal nerve)
prevalence of back pain
10%
lifetime prevalence of back pain
80%
disease burden of back pain
psychological problems
lots of people off work
leading cause of disability globally
causes of back pain
- scoliosis
- herniated/ prolapsed disc
- cancer
- sciatica
- trauma
- pregnancy
- mechanical – heavy lifting etc.
- pathological fractures
- ankylosing spondylitis
- nerve compression
- kyphosis
- bad posture
- HIV
- depression
- trauma
- fragility fractures
- stress fracture
- infection – intervertebral disc
- sclerosis
- cauda equina syndrome – compression of cauda equina
- arthritis
red flags for back pain
unexplained weight loss urinary retention young age new pain PMH of cancer bladder symptoms lumps thrombocytopenia neurological deficit sexual dysfunction saddle anaesthesia fever recent travel fatigue thoracic back pain
cauda equina syndrome
compression of cauda equina
urinary retention
saddle anaesthesia
causes of referred back pain
kidney stones pyelonephritis MI menstrual pain endometriosis duodenal ulcers pancreatitis abdominal aortic aneurysms thoracic aortic aneurysms
mechanical back pain
97% of back pain
imaging for back pain
MRI is gold standard if concerned about cord progression or neurological symptoms
X-ray not normally needed in absence of red flag symptoms
what age is back pain most concerning?
<20 year olds = very concerning
>55 year olds back pain = higher risk of serious causes such as AAA or cancer
vertebral artery
runs through transverse foramen of cervical vertebrae
carries blood supply to posterior of brain - brainstem, cerebellum and posterior cerebral cortex
elderly can occlude this
C1
no vertebral body
C2
has dens/ peg
C7
spinous process = prominent and palpable
body of cervical vertebrae
small
wide
side to side
spinous process of cervical vertebrae
short bifid
projects posteriorly
vertebral foramen of cervical vertebrae
contains vertebral artery
triangular
transverse process of cervical vertebrae
contain foramina
movements of cervical vertebrae
flexion
extension
lateral flexion
rotation
body of thoracic vertebrae
larger than cervical
heart-shaped
2 costal demifacets
spinous process of thoracic vertebrae
long
sharp
projects inferiorly
vertebral foramen of thoracic vertebrae
circular
transverse process of thoracic vertebrae
facets for ribs - except T11 and 12
Movements of thoracic vertebrae
rotation
limited lateral flexion due to ribs
flexion and extension prevented
body of lumbar vertebrae
massive
kidney shaped
spinous process of lumbar vertebrae
short
blunt
projects posteriorly
vertebral foramen of lumbar vertebrae
triangular
transverse process of lumbar vertebrae
thin and tapered
movements of lumbar vertebrae
flexion
extension
some lateral flexion
rotation prevented
intervertebral disc
between vertebra
degenerates over time causing height loss
structure of intervertebral discs
centre = nucleus pulposus
outer layer = annulus fibrosis
what happens in a herniated disc?
rupture of annulus fibrosis and nucleus pulposus seeps out
can cause compression of spinal nerve
caudal epidural
given through sacral hiatus
interlocking vertebrae
superior and inferior articular processes form the joint
intervertebral foramen between the 2 vertebrae
intervertebral foramen
where spinal nerve leaves spinal cord
arthritis
can cause compression of spinal nerve
what are the ligaments of interlocking vertebrae
supraspinous interspinous ligamentum flavum anterior longitudinal posterior longitudinal
where does the spinal cord end?
L1
extends more inferiorly in babies and shorter people
lesion of cauda equina
causes lower motor neuron lesion signs
L4
vertebra is level with iliac crest
level for lumbar puncture as this is where the cauda equina is so won’t cause damage
where does the subarachnoid space end?
S2
test for scoliosis
bend over
one side will go lower than the other
caudal epidural injections
used during birth process
