Flashcards in Practical 1 - The vertebral column and spinal cord Deck (78):
A typical vertebral column has how many vertebra?
What does the body of a typical vertebra support and what is it connected to?
Supports - vertebral column
Connected to - intervertebral discs
What are the subdivisions of the vertebral arch of a typical vertebra?
3. Paired superior and inferior articular processes which protrude posterior to the vertebral notches
4. Spinous and transverse processes
What do the spinous and transverse processes allow?
attachments of muscles and ligaments
What region of vertebra is the smallest?
What is a distinctive feature of cervical vertebra?
transverse foramina (foramen transversarium)
What are the transverse foramina (foramen transversarium) like in C7?
smaller or absent than the other cervical vertebra
What structure passes through the transverse foramina?
vertebral arteries and veins
Which cervical vertebral don't follow the typical vertebra structure?
C1 (atlas) and C2 (axis)
What are the spinous processes of C3 to C6 vertebrae like?
short and bifid
What is the spinous process of C7 like and what is it used as?
used as - bony landmark to count vertebra
What is another name for C7?
What are the features of C1 (atlas)? (3)
1. no spinous process
2. anterior and posterior arches
3. tubercle each on medial surface of the lateral mass for the transverse ligament
What are the features of C2 (axis)? (2)
1. 2 large flat surfaces producing the superior articular facets
2. dens/ odontoid process
What is the vertebral body of thoracic vertebrae like?
- has superior and inferior costal demi facets which articulate with the head of the rib
What is the spinous process like for thoracic vertebrae?
- extends posteroinferiorly
What is the transverse process for thoracic vertebrae like?
- costal facet for articulation with tubercle of rib
What direction do the articular facets in thoracic vertebrae face?
- superior articular facets face posteriorly
- inferior articular facets face anteriorly
What is the vertebral body like for lumbar vertebrae?
What direction do articular facets facets face in lumbar vertebra?
- superior articular facets face medially
- inferior articular facets face laterally
What is the spinous process like for lumbar vertebrae?
- short and sturdy
What are vertebrae held together by? (3)
- facet joints
- intervertebral discs
What are facets joints also known as and what do they connect?
- zygapophyseal joints
- connect superior and inferior articular processes of adjacent vertebrae
Where are intervertebral discs found?
- all non-fused vertebrae
What do intervertebral discs do?
- provide flexibility to the spine
- acts as shock absorbers
What do ligaments do?
- bind the vertebrae together to provide stability
What is the intervertebral disc composed of? (2)
- annulus fibrosus
- nucleus pulposus
What is the structure and location of annulus fibrosus?
structure - fibrocartilage ring
location - attached to epiphyseal rim of vertebral body (outer ring)
What is the structure and location of the nucleus pulposus?
structure - gelantinous substance - shock absorber
location - inner ring
What are the attachments of the anterior longitudinal ligament? (2)
- occipital bone
- C1 to Sacrum
What is the function of the anterior longitudinal ligament?
resists hyperextension of the vertebral column
What are the attachments of the posterior longitudinal ligament?
C2 to Sacrum
What is the function of the posterior longitudinal ligament?
prevents posterior herniation of IV discs and resists hyper flexion
What are the attachments of the ligamentum flavum?
between laminae of adjacent vertebrae
What is the function of the ligamentum flavum?
- binds lamina of adjacent vertebrae
- resists separation of laminae in flexion
- assists extension back to anatomical position
What are the attachments of ligamentum nuchae? (6)
- base of triangle
- external occipital protuberance to foramen magnum
- apex --> CVII spinous process
- deep side -posterior tubercle of C1
- spinous process of other vertebrae
What is the function of ligamentum nuchae?
- supports the head
- resists flexion
- facilitates returning to normal anatomical position
- attachment for adjacent muscles
What are the attachments for interspinous ligaments?
- between adjacent vertebral spinous processes
- base to the apex of each spinous process
what is the function of interspinous ligaments?
limits flexion of spine
What grows at a faster rate - the vertebral column or spinal cord?
At which vertebral level does the spinal cord end in a newborn?
At which vertebral level does the spinal cord end in an adult?
What meninges cover the spinal cord? (3)
- dura mater
- arachnoid mater
- pia mater
What is the space between the dura and arachnoid mater called?
What is the space between the arachnoid and pia mater?
What does the subdural space contain?
potential space with lymph like fluid
What does the subarachnoid space contain?
What is the space between the dura and the vertebrae called?
epidural or extradural space
What does the epidural or extradural space contain?
- small blood vessels
Where do the anterior and posterior spinal arteries originate from?
What does the anterior spinal artery supply?
anterior 2/3rds of the spinal cord
What does the posterior spinal artery supply?
posterior 1/3 of spinal cord
What is the venous drainage like for the spinal cord?
1. anterior and posterior spinal veins
2. anterior and posterior radicular veins
3. communicate with internal vertebral plexus in epidural space
4. drains into the cerebral dural venous sinuses and cerebral veins and external vertebral plexus
What is a distinctive feature of spinal veins of the spinal cord?
they are valveless so that blood passes directly into the systemic venous system
What do each vertebral level connect to in terms of veins?
- intercostal veins
- external vertebral venous plexus
What is the path along which prostatic neoplastic cells metastasise to the central nervous system?
- along the continuity of the vertebral venous plexus with the prostatic plexus
What is the caudal equina?
- collection of dorsal and ventral roots of the lower lumbar, sacral and coccygeal segmental spinal nerves.
- bundle of spinal nerves and roots
What nerves does the caudal equina involve and where do they arise from?
L2-L5 and S1-S5 and Co1
- these arise from the lumbar enlargement and conus medullaris
What does the spinal nerve emerge as in the upper part of the vertebral canal through the intervertebral foramen?
- anterior primary ramus and posterior primary ramus
What 2 groups can the muscles of the back be divided into?
1. deep (intrinsic)
2. superficial (extrinsic)
What are the extrinsic muscles of the back innervated by?
- ventral rami of spinal nerves
- accessory nerve
What are the extrinsic muscles of the back divided into?
- intermediate groups
What muscles are involved in the superficial division of the extrinsic back muscles? (5)
1. rhomboid major
2. rhomboid minor
4. latissimus dorsi
What muscles are involved in the intermediate division of the extrinsic back muscles? (2)
1. Serratus posterior superior
2. Serratus posterior inferior
What do the intermediate extrinsic back muscles act as?
weak accessory muscles for respiration
What are the intrinsic back muscles innervated by?
posterior rami of spinal nerves
What 3 groups are the intrinsic back muscles divided into?
What does the superficial group of the intrinsic back muscles contain?
the splenius muscles on the posterolateral surfaces pf the neck
What 2 parts can the splenius muscles be divided into and what does this division depend on?
1. Splenius capitus
2. Spenius cervicus
depends - on their insertions
What are the attachments of the splenius captius? (5)
1. Lower 1/2 of ligamentum nuchae
2. spinous process of CVII to TIV
3. mastoid process
5.below lateral 1/3 of superior nuchal line
What is the action of the splenius capitus? (2)
1. draw head backwards extending the neck
2. draw and rotate head from one side to the other - turning face to one side
What are the attachments of the splenius cervicis?
1. spinous process of TIII to TVI
2. transverse processes of CI to CIII
What is the action of splenius cervicis?
1. extend neck
2. draw and rotate head to one side - turn face to one side
What does muscles the intermediate group of the intrinsic back muscles compromise of and where do they lie?
Large erector spinae muscles
lie - each side of the vertebral column
What is the function of the erector spinae muscle?
- main extensor of the vertebral column
What 3 muscles forms the erector spinae muscle?
Where do the deep group of intrinsic back muscles originate and insert and what is this group called?
originate - transverse processes of the vertebrae
insert - spinous process of more superior vertebrae
called - transversospinalis group