Back and Vertebral Column Flashcards
4 curves of spine
Cervical lordosis
Thoracic kyphosis
Lumbar lordosis
Sacro-coccygeal kyphosis
How many vertebrae make up the spine?
The spine is made of 32 to 33 vertebrae. The vertebra is the fundamental unit of the spine.
The vertebrae in the lower portion of the column have larger bodies than those in the upper portion, to better support the increased weight
5 regions of spinal cord
C1-C7 T1-T12 L1-L5 S1-S5 Cox1-Cox-3
Which vertebrae is this
Which vertebrae is this
Dens of axis
Thedens actsas a pivot that allows the atlas and the above occipital bone and head to rotate on theaxis, side to side.
Which cervical vertebrae can be easily palpated?
C7
What are these?
Label each part
body pedicles transverse processes spinal cord (blue) lamina spinous process
Which vertebra is this?
Which vertebra is this?
Sacrum and coccyx
Which vertebrae have the transverse foramen?
Only cervical
Which vertebrae have bifid spinous processes?
Cervical minus C7
How do vertebrae articulate?
Intervertebral discs
Vertebral discs provide strong attachments between vertebral bodies
They account for around 20-30% of the total spine length
They serve as shock absorbers
The discs are formed by two areas; an outer anulus fibrosus and an inner nucleus pulposus
Spinal cord termination
The spinal cord is a long, thin, tubular structure made up of nervous tissue, which extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column.
It terminates approximately at the level of L1, from there a series of spinal nerves branch off to form a structure called “cauda equina”, which means “horse’s tail”
Spinal meninges
Denticulate ligament
Comes off pia mater and laterally anchors spinal cord to meninges
Spinal nerves
31 pairs
Note that we have 8 pairs of cervical spinal nerves on each side of the spine called C1 through C8. This is because the first pair pass between the skull and C1 so we possess 7 cervical vertebrae but 8 cervical nerves.
What extends from sides of vertebral body to join body to arch?
The pedicle connects the vertebral body to the vertebral arch and more specifically it sits between the vertebral body and the transverse process of the vertebra.
Where does spinal nerve 8 sit?
Spinal nerve C8 exits between C7 and T1. C1 spinal nerve arises just below the occipital bone.
Anterior ligaments
The anterior longitudinal ligament (ALL) arises from the occipital bone, traverses the entire length of the spine along the anterior aspect of the body of the vertebrae, and ends on the antero-superior portion of the sacrum.
It broadens as it descends.
Posterior longitudal ligament arises from…
Theposterior longitudinal ligament (PLL)arises from the back of theaxis(C2) body andtravels downward andattaches posteriorly to the vertebral bodies andintervertebral discs, attaching to the back of thesacrum.
Itnarrows as it descends.
What does the interspinous ligament join?
The interspinous ligament joins the spinous processes.
It fuses with the strong, supraspinous ligament
What does the supraspinous ligament join?
Thesupraspinous ligamentjoins the tips of the spinous processes.
What is the ligamentum flavum?
Theligamentum flavumis a paired ligament which runs between the adjacent lamina of the vertebral bodies.
It is a paired, yellowish, elastic ligament. It starts off relatively thin in the cervical spine to progressively become thicker in the lumbar spine.
Ligamentum nuchae
The ligamentum nuchae is a large median ligament composed of tendons and fascia located between the posterior muscles of the neck.
It spans from the external occipital protuberance and median nuchal line to the spinous process of C7, attaching all the posterior tips of C1 to C6 spinous processes.
It is an extension of the supraspinous ligament.
It is thick and strong, limiting hyperflexion of the neck.
What do intertransverse ligaments join?
Theintertransverse ligamentsjoin transverse processes of adjacent vertebrae.
These are very thin fibrous cords.
What is a ligament made of?
Skeletal ligaments are defined as dense bands of collagenous tissue (fibres) that span a joint.
function of ligament
Increase stability of the spine, restrict movements that may damage the joint.
Back muscle groups
2 superficial intrinsic muscles
There are 2 superficial intrinsic muscles:
the splenius capitis and splenius colli (or splenius cervicis).
Function: rotation of the head (same side); extension of the neck; also involved in lateral flexion of the neck (same side).
Splenius capitis
3 intermediate intrinsic back muscles
The iliocostalis, longissimus and spinalis. Together these muscles form a column, known as the erector spinae.
Function: they all act unilaterally to cause lateral flexion of the vertebral column. They also contract bilaterally to extend the vertebral column and head. In addition, the connection with the pelvis also helps stabilise the column.
Deep group or transversospinalis muscles
The deep intrinsic muscles are located underneath the erector spinae.
the semispinalis, multifidus and rotatores.
They are a group of muscles associated with the transverse and spinous processes of the vertebral column.
Function: stabilise the spine by holding together the vertebrae; the semispinalis extend (bilateral contraction) and rotate (unilateral contraction) the head, neck and trunk.
What muscle is this?
Rotatores
Minor deep intrinsic muscles or segmental muscles
Interspinales: spans between adjacent spinous processes. Acts to stablise the vertebral column.
Intertranversari: spans between adjacent transverse processes. Acts to stablise the vertebral column.
Levatores costarum: originates from the transverse processes of C7-T11, and attaches to the rib immediately below. Acts to elevate the ribs.
Rectus abdominis
The rectus abdominis muscle is not attached in any way to the spine but, among the other functions, it is responsible for flexion of the trunk.