spine and trunk Flashcards
what is the spine?
- rigid bone structure made of many vertebrae
describe the structure of the spinal cord (33 vertebrae)
- 12 thoracic
- 7 cervical
- 5 lumbar
- 5 sacrum
- 4 coccyx
what are the six functions of the spine?
- weight bear in upright posture
- act as shock absorber through curves and discs
- produce, accumulate and transmit force
- attachment point for muscles of shoulder
- carry/ support the thoracic cavity
- protects spinal cord
what is the role of the curves?
- maintain balance while standing upright and sitting
what are primary curves?
- curves developed before birth
what are the two types of primary curves and what are they known as?
- thoracic and pelvic curvature
- known as kyphosis
what are secondary curves?
- curves developed after birth
what are the two types of secondary curves and what is it known as?
- cervical and lumbar curvature
- known as lordosis
when are secondary cervical curves developed?
- when a baby learns to sit
when are secondary lumbar curves developed?
- as a toddler learns to walk
what are the three types of increased curves?
- hyper kyphosis, hyper lordosis and scoliosis
what is scoliosis? when is it normally identified?
- abnormal curve in frontal plane
- commonly idiopathic
- identified in childhood
- can be secondary to other conditions
what are the cervical spinal movements that are allowed?
- flexion and extension= 45’
- right and left rotation= 80’
- lateral flexion= 45’
what are the thoracolumbar movements?
- flexion (90’) and extension (30’)
- lateral flexion (30’)
- lateral rotation (30’)
what movement is limited in thoracic spine?
- limited flexion/ extension
what movement is limited in lumbar spine?
- more limited rotation
what is the point of the body in the cervical spine?
- supports the weight
describe the spinous processes of the cervical spine
- bifid spinal process found on back
- two bumps instead of one to help attachment
what joins the spinous process to the transverse process in cervical spine?
- lemina
- these three form the vertebral arch
what is the facet joint formed by in the cervical spine?
- formed by superior and inferior articular process
what is the greatest range of motion of the cervical spine?
- 45 degrees
what is each vertebrae connected to in the thoracic spine?
- connected to a pair of ribs; 1-7 directly whereas 8-12 indirectly attached
why does thoracic spine have a larger body?
- supports a greater weight
what is the facet called where the ribs attach (thoracic) ?
- coastal facet
which way does the superior articular process face in the thoracic spine?
- either faces forwards or backwards
what determines the movement of the thoracic spine?
- structure of the articular process
what is the size of the neural canal in the thoracic spine?
- smaller neural canal
why is movement limited in the thoracic spine?
- 65 degree angle
- ribs articulate and attach to vertebrae
why does lumbar spine have the largest body?
- bears the greatest weight
describe the transverse process of the lumbar spine
- short but stronger transverse process
why does the lumbar spine have the lowest range of motion?
- angle of articular process is 90 degrees so little rotation
compare the vertebral body of cervical, thoracic and lumbar spine
C= small oval
T= medium heart
L= large kidney shaped
compare the vertebral foramen of cervical, thoracic and lumbar spine
C= large triangular
T= small oval
L= small triangular
compare the spinous process of cervical, thoracic and lumbar spine
C= short and bifid
T= long slanted down
L= broad and flat
compare the transverse process of cervical, thoracic and lumbar spine
C= shorter, more anterior + transverse foramen
T= longer, more posterior+ costal facets
L= longer more lateral
compare the facet joint of cervical, thoracic and lumbar spine
C= 45 degrees anteroposterior
T= 60 degrees anteroposterior
L= 90 degrees mediolateral
what does spinal cord run along?
- neural canal
what are vertebral bodies separated by?
- intervertebral discs
where are articulations between vertebras at?
- zygapophyseal joints
what do the transverse and spinous processes provide?
- attachment for muscles
what does the transverse foramen allow?
- allows arteries through on either side of cervical spine
- form part of blood supply to brain alongside internal carotid arteries
what is the atlas?
- 1st cervical vertebrae
describe the structure of the atlas
- no body
- consists only of occipital process and transverse process
what does the atlas articulate with?
- base of skull at atlantooccipital joint
describe the size of articular facets in atlas and why
- large articular facet to support the skull
what is the axis?
- 2nd cervical vertebrae
how does axis connect to atlas?
- via dens
- allows rotation
which joint does axis use to articulate with atlas?
- atlantoaxial joint
what does axis consist of?
- superior articular process and transverse process
what forms axis of rotation of atlanto- axial joint? what rotation is formed?
- dense
- generates cervical rotation
what ligament is in the atlanto-axial joint and what is its role; what does it hold in place?
- transverse ligament on posterior side
- prevents forwards or backwards movement
- holds odontoid process in place
why is axis useful for rotation?
- due to peg orientation
what is the atlanto- occipital joint?
- articulation of atlas and occipital processes of the cranium
what movement is produced by the atlanto- occipital joint?
- cervical flexion and extension
what is each vertebrae connected to?
- a pair of ribs
how are ribs 1-7 attached?
- directly attached to sternum
how are ribs 8-12 connected?
- indirectly attached via intercostal cartilage
- not physically attached
what are ribs 11 and 12 described as?
- floating ribs
what is the definition of ligaments of the spine?
- connective tissue that acts to stabilise the spine
- protects vertebrae
where is the superior spinous ligament found?
- found on top of spinal process
what is the role of the ligaments between the transverse process?
- keep the vertebrae in place
where does the anterior longitudinal ligament sit?
- stays in front of vertebra from cervical down to coccyx
what surfaces does the anterior longitudinal ligament cover?
- covers anterolateral surface of vertebral bodies and IV discs
what is the role of the anterio- longitudinal ligament?
- protects and stabilises the joint
- contains several layers and prevents hyperextension
what do you see if you go another layer deep to anterior longitudinal ligament?
- IV discs in-between two vertebra to support their place and bear weight
describe ligaments in relation to the transverse processes
- small ligaments attach to TP between 2 vertebra
- small ligaments inside TP to keep spine in place/ limits movement
where is the posterior longitudinal ligament found?
- found on back of vertebral body
what is the role of the posterior longitudinal ligament?
- keeps spine in place within vertebral canal
- attached to intervertebral discs along its length
what is the strength of the posterior ligament compared to the anterior ligament?
- weaker as it is narrower compared to anterior
what does the posterior longitudinal ligament resist?
- hyperflexion of vertebral column
what does the posterior ligament combined with anterior ligament do?
- keep the spine and intervertebral disc in place
what is the inter spinous ligament?
- thin broad ligaments between the spinal process
what is the ligament on top of the interspinous ligament called and what is its role?
- supraspinous ligament as sits on top of the spinous process
- supports spine shape and assists movement
what are intervertebral discs important for?
- support and weightbearing
- they move as you move
what is the point of the anulus fibrosis?
- keeps central part (nucleus pulposus) in place
- outer layer
what is the nucleus pulposus and what does it do?
- spongey structure
- absorbs impact
- distributes weight evenly into discs for weight bearing functions
what is the ligamenta flava known as? and what is it?
- yellow ligament
- series of ligaments that connect ventral parts of laminae of adjacent vertebra
what is the ligamenta flava formed by?
- 80 % elastin fibres and 20% collagen
what are the roles of the ligamental flava?
- preserve posture and prevent hyperflexion
what happens to the discs when we move?
- as we move, the discs also move
- if we bend pressure pushes discs back
- if we extend the body the disc goes forwards
what is the disc pressure?
- standing up pressure is around 100
- pressure decreases when we lay down
what does bending forward do to pressure and what does this challenge?
- bending forward increases pressure
- higher pressure challenges anulus fibrosis more
what happens to anulus fibrosus as we get older?
- structure becomes weaker so accidents may happen
- means nucleus pulposus may push anulus fibrosus to different direction
what is the intervertebral foramen?
- space between vertebrae to allow for passage of nerves
what do the nerves innervate?
- either skin or muscles
what does the space between two vertebrae consist of?
- inferior vertebral notch and superior vertebral notch
what is the inferior vertebral notch?
- top of space; part of the vertebral pedicle
- short projection of bone that connects body to vertebral arch
where is the superior vertebral notch? what is it closer to?
- on the bottom
- closer to the superior articular process
what is the zygapophyseal facet joint?
- synovial joint that connects the vertebra in the spine
how many facet joints are in each spinal motion segement?
- two
how can the IV discs cause problems?
- if the discs move back then it can touch the spinal nerve and cause problems
what are herniated discs?
- bulging disc occurs due to weakening anulus fibrosis
what happens to the nucleus pulposus if there is a herniated disc?
- when injured or aging the anulus becomes weaker so when spine moves the nucleus may come out
- causes a change in shape and bulge may touch nerve =pain
what are degenerated discs?
- natural ageing process
- results in flatter disc
- so anulus fibrosis cannot keep nuclear pulposus in place
how do degenerated discs cause irritation?
- height of disc becomes lower so reduced space for foramen
- spinal nerve space becomes smaller so nerve may be touched by bony structure
what is the sternum?
- bony structure that sits in front of the cage
what is the diaphragm?
- key muscle at bottom of ribcage
- important muscle for breathing
what happens to diaphragm when muscle contracts?
- moves downwards to increase space of thoracic cage
- reduces pressure inside cage so air goes up through nose
what happens to the diaphragm when the muscles relax?
- moves upwards to reduce space of thoracic cage
- increases pressure to push air out through the nose
what muscle helps forceful exhalation?
- internal intercostals pushes ribs downwards to reduce space
- increases pressure
what muscle aids in forced inhalation?
- external intercostal muscles lift up the ribcage and reduce pressure
- allows more air into the thoracic cage
what are global movers?
- involved in generation of torque and range of motion
- larger and produce more movement
what is the function and dysfunction of global movers?
Function= phasic manner and movement depends on direction
Dysfunction= spasm, pain and restricted ROM
what are local stabilisers?
- deeper muscles controlling the segmentation of the spine
- help with stability and posture
- produce continuous activity w low force
- maintain curvature of the spine
what is the function and dysfunction of local stabilisers?
function= activity is tonic and low for long periods of time
dysfunction= inhibition of function, delayed timing or recruitment deficiencies; loss of segmental control
where do neck flexors sit?
- anteriorly
state the origin, insertion and action of the platysma
O- mandible
I- clavicle
A- superficial neck flexor; depresses mandible and tenses skin
state the origin, insertion and action of sternocleidomastoid
O- sternum + clavicle
I- posterior mastoid
A- superficial neck flexor/ contralateral rotation
state the origin, insertion and action of anterior scalenes
O- transverse process of C3- C6
I- 1st rib
A- deep neck ipsilateral flexor/ contralateral rotator
state the origin, insertion and action of longus cervivis
O- transverse process of C3-T5
I- transverse process of C1-C6
A- deep neck flexor
state the origin, insertion and action of upper trapezius
O- spinous process of C7
I- clavicle
A- superficial neck extensor
state the origin, insertion and action of splenius cervicis
O- spinous process of C3-C6
I- transverse process of C1-C3
A- superficial neck extensor
state the origin, insertion and action of splenius capitis
O- spinous process of C7
I- clavicle
A- superficial neck extensor
state the origin, insertion and action of levator scapulae
O- scapula
I- cervical column
A- deep neck extensor
state the origin, insertion and action of semispanalis capitus
O- transverse process of T1-T6
I- occipital bone
A- deep neck extensor
state the origin, insertion and action of semispinalis convicis
O- transverse process of T1-T6
I- spinous process of C2-C5
A- deep neck extensor
state the origin, insertion and action of external oblique
O- 5th -12th rib
I- ilium
A- superficial trunk flexor/ ipsilateral flexion/ contralateral rotation
state the origin, insertion and action of internal oblique
O- iliac crest
I- costal cartilage of ribs 8-12
A- deep trunk flexor/ ipsilateral flexion/ ipsilateral rotation
state the origin, insertion and action of rectus abdominus
O- pubis crest
I- cartilage of 5th- 7th ribs
A- superficial trunk flexor
state the origin, insertion and action of transverse abdominus
O- iliac crest
I- xiphoid process+ linea alba
A- deep trunk flexor
what does the transverse abdominus maintain?
- curvature of spine and abdominal wall
describe the structure of the abdominal wall
- external oblique is the most superficial, then internal and finally transverse abdominis is the most deep layer
what does external, internal oblique and transverse abdominus form?
- form a connective tissue to wrap around the rectus abdominus to keep muscle in place
how is fascia on both sides joined together in the centre of the trunk?
- linea alba
- ends just above the umbilicus
state the origin, insertion and action of erector spinae
O- iliac crest and sacrum
I- posterior ribs, occipital bone and cervical transverse process
A- trunk extensor
what does erector spinae contain?
- illicoastalis, longissimus, spinalis
state the origin, insertion and action of semispinalis
O- transverse process of C4-C6
I- spinous process of C7-T1
A- trunk extensor
state the origin, insertion and action of multifidus
O- posterior iliac crest
I- inferior border of 12th rib and transverse process of L1-L4
A- trunk extensor
state the origin, insertion and action of quadratus lumborum
O- posterior iliac crest to 12th rib
I- transverse process of L1- L4
A- trunk extensor
what quadratus lumborum stabilise?
- stabilises pelvis and lumbar spine
