Week 5 - Spine & Thoracic Cage Flashcards
List the structure of the spine
Cervical v (C1-C7)
Thoracic v (12)
Lumbar v (5)
Sacrum (5)
Coccyx
Where are intervertebral discs
Between bodies of adjacent vertebrae from C2 to sacrum
What % of height of vertebral column do the intervertebral discs account for?
25%
Annulus fibrosus
Fibrous ring on outer part of intervertebral discs
Consists of fibrocartilage.
Nucleus pulposus
Inner soft, high elastic substance in intervertebral disc.
Vertebral body
Thick, disc shaped anterior portion
Weight-bearing
Roughened superior + inferior surfaces for attachment of cartilaginous intervertebral discs.
Vertebral arch
Extends posteriorly from the vertebral body
How many processes arise from the vertebral arch?
7
Which processes act as muscle attachment points?
Transverse
Spinous
Transverse process
Extends laterally on each side where lamina + pedicle join
Spinous process
Projects posteriorly from junction of laminae
What do the last 4 processes do? (Ones that don’t act as muscle attachment points)
Form joints w/ other vertebrae above or below.
What are the last 4 processes
2 superior articular processes
2 inferior articular processes
What do the 2 superior articular processes articulate with?
2 inferior articular processes of vertebra immediately above
What do the 2 inferior articular processes articulate with?
2 superior articular processes of vertebra immediately below.
Compare the cervical vertebrae to other vertebra
Bodies are smaller - except those that form the coccyx.
Larger vertebral arches
How many foramina do cervical vertebrae have
3
What passes through the transverse foramen
Vertebral artery + its accompanying vein + nerve fibres.
Bi-fid
Branch into 2 small projections at the tips.
Which spinous processes are often bi-fid?
Those of C2-C6
Describe the foramen of cervical vertebrae
Large
Triangular
How many transverse foramen do the cervical vertebrae have?
2
Describe the pedicle of a cervical vertebrae
Small
wide
Body of the cervical vertebra
Small
Describe Atlas (C1)
No vertebral body
Forms atlanto-occipital joint w/ skull.
Describe axis (C2)
Dens process
Allows rotation of head
Movements at the cervical vertebrae
Flexion
Extension
Lateral flexion
Movements at the thoracic vertebrae
Rotation
Movements at the lumbar vertebrae
Flexion
Extension
Lateral flexion
Movements at the sacral vertebrae
No movement
Movements at the atlanto-occipital vertebrae
Flexion
Extension
Movements at the atlanto-axial vertebrae
Rotation only
Describe the thoracic cage
Bony enclosure formed by the sternum, ribs + their costal cartilages.
What do costal cartilages do
Attach ribs to sternum
Sternal angle
Junction of the manubrium + sternum body.
Suprasternal notch
Depression on superior surface of the manubrium
Clavicular notches
Lateral to the suprasternal notch
Articulate w/ medial ends of clavicles = Sternoclavicular joints
Xiphoid process
provides attachment for some abdominal muscles
Sternocostal joints
Articulations formed between the true ribs + sternum
Vertebrochondral ribs
Costal cartilages attach indirectly to sternum or not to sternum at all.
Describe spinal extension
Brings a flexed spine back to the anatomical position + beyond
What happens of the concentric contractions during spinal extension
Concentric contractions of posterior muscles
What happens with the insertions + origins during spinal extension
Insertions move toward origins
Origins are inferior to insertions
Sternal body
Extends from T5-T9.
Where can the Clavicular fossa be found?
On superolateral angles of manubrium
THORACIC VERTEBRAE
Vertebral foramen
Small + round
THORACIC VERTEBRAE
Vertebral body
Heart-shaped
THORACIC VERTEBRAE
Spinous process
Long + thin
THORACIC VERTEBRAE
Transverse process
Large
How many pairs of ribs are there
12
Where do ribs 1-7 attach?
Anteriorly to the sternum via costal cartilage
== True ribs
Where do ribs 8-10 attach?
7th costal cartilage
== False ribs
Where do ribs 11-12 attach?
No where – “floating ribs”.
Describe the 1st rib
Short
Broad
Flattened
Head of 1st rib
Located on posterior aspect of rib
Small
Rounded
What action do the interspinous + supraspinous muscles limit?
Trunk flexion
What action do the anterior + posterior longitudinal ligaments limit?
Hyperextension
Flexion
Extension
What action do the rotatores muscles allow?
Extension
Rotation
What action do the Interspinales muscles allow
Extension
Intertransversarli muscles
Lateral flexion
Provide stability to spinal column
What 3 groups do the back muscles get split into?
Erector spinae
Transversospinalis
Superficial
Erector spinae
Forms large bulk of muscle lying in groove on either side of vertebral column.
What 3 main sections is the erector spinae divided up into?
Iliocostalis
Longissimus
Spinalis
What comes under the iliocostalis muscles
Iliocostalis cervicis
Iliocostalis thoracis
Iliocostalis lumborum
Origin + insertion for Iliocostalis cervicis
O = Ribs 3-5
I = C4-C6 – At the posterior tubercles of the transverse processes.
Action for the Iliocostalis cervicis
Extension
Lateral flexion
Rotates
– All for the vertebral column
Origin + insertion for Iliocostalis thoracis
O = Ribs 7-12
I = Ribs 1-6
Action for the Iliocostalis thoracis
Extension of thoracic if both!
Ind will laterally flex thoracic spine.
Iliocostalis lumborum
Long muscle of posterior lumbar vertebral column.
Origin for the Iliocostalis lumborum
Sacrum
L1-L5 - Spinous processes
Hip bone - iliac crest
Insertion for the Iliocostalis lumborum
Ribs 7-12
Angles
Action for the Iliocostalis lumborum
Together - extend the spine
Ind. - Lateral flexion of spine
What comes under the longissimus muscle group
Longissimus capitis
Longissimus cervicis
Longissimus thoracis
Origin for Longissimus capitis
T1-T5
C4-C7
Insertion for Longissimus capitis
Temporal bone
Action for Longissimus capitis
Together - Extend the head.
Ind. – muscle will turn face to the same side.
Origin for Longissimus cervicis
T1-T5
Insertion for Longissimus cervicis
C2-C6
Action for Longissimus cervicis
Extends + laterally flexes vertebral column.
Origin for Longissimus thoracis
L1-L5
Insertion for Longissimus thoracis
T1-T12
Ribs 4-12
Action for Longissimus thoracis
Together - Extend thoracic spine
Ind - Laterally flex thoracic spine
What comes under spinalis
Spinalis capitis
Spinalis cervicis
Spinalis thoracis
Origin for the Spinalis capitis
C4-T7
C4-C6
C7
Insertion for Spinalis capitis
Occipital bone
Action for Spinalis capitis
Together - extend head
Ind - face towards opp. side
Origin + insertion for Spinalis cervicis
O = C7
I = C2
Action for Spinalis cervicis
Extension of vertebral column
Origin + insertion for Spinalis thoracis
O = C7
I = C2
Action for Spinalis thoracis
Extension of cervical spine.
What indents on the sternal lateral borders?
Facets for costal cartilages 2-7
What does the clavicular fossa articulate with?
Sternal end of clavicle.
