Class 8 - THE SKELETON OF THE VERTEBRAL COLUMN AND THE THORAX Flashcards
Functions of the vertebral column
Support the head, allows for movements and attachment of the muscles of the trunk
Point of attachment for the ribs, pelvic girdle, and upper extremities
Partially supports the trunk and surrounds and protects the spinal cord
Portions of a typical vertebra
Body
Vertebral arch
Seven vertebra processes
The body of the vertebra
Disc-shaped weight-bearing portion
Rough superior and inferior surfaces for the attachment of intervertebral disc
The vertebral arch
Formed by the union of the pedicles and laminae of both side in the middle
Surrounds and protects the spinal cord by forming the vertebral foramen
Vertebral foramen contains
Connective tissue, fat, and blood vessels
Surrounds the spinal cord
Intervertebral foramina
Space in between the vertebrae that allow for the passage of spinal nerves
The seven vertebral processes
Transverse processes (2)
Spinous process (1)
Superior articular processes (2)
Inferior articular processes (2)
Facets joints (planner synovial) are formed by
Superior and inferior articular processes
Five regions of the vertebral column
- Cervical
- Thoracic
- Lumbar
- Sacral
- Coccygeal
Number of vertebral curves in fetus and newborn
One
Number of vertebral curves in adults
Four (after age 10)
Lordosis
Concave curve in lateral view
- Cervical lordosis
- Lumbar lordosis
Kyphosis
Convex curve in the lateral view
- Thoracic kyphosis
- Sacro-coccygeal kyphosis
Primary vertebral curvatures
Thoracic kyphosis
Sacro-coccygeal kyphosis
Secondary vertebral curvatures
Cervical lordosis
Lumbar lordosis
Intervertebral discs are formed by
Annulus fibrosus (outer fibrous ring)
Nucleus pulposus (inner soft, elastic substance)
Intervertebral disc form
Cartilaginous joints between adjacent bodies and absorb vertical shock
Intervertebral discs lose water during the…
Day, due to compression
Intervertebral discs rehydrate…
While sleeping
Blood vessels from the body of the vertebrae provide…
Intervertebral discs
Nourishment for the avascular intervertebral discs
Nucleus pulposus hardens…
With age
Herniated (slipped) disc
Excessive pressure on the nucleus pulposus may rupture the annulus fibrosus causing the nucleus pulposus to protrude through the ruptured area
Herniated discs occur most commonly in
Lumbar region
Cervical region
Typical cervical vertebrae
C3-C6, bifurcated and container transverse foramina
Cervical vertebrae foramina
Transverse foramina (2) only present in cervical vertebrae
Vertebral foramen (1)
Atypical cervical vertebrae
C1, C2, and C7
Atlas (C1)
Has no body, nor spinous process
Has two lateral masses with concave superior articular facets
Axis (C2)
Has body with a superior projection (dens)
C7
Prominent and transitional vertebrae, has longest spinous process that is not biforcated.
Thoracic vertebrae
12
Only vertebrae that articulate with the ribs
Longer and larger transverse processes
Spinous processes are long and directed inferiorly
Contain costal facets for the ribs
Ligamentum Nuchae
Ligament that covers the posterior side of C1-C6 to help keep the neck stable
Costal facets articulate with the ribs with the corresponding vertebrae in two joints
- Costovertebral joint
2. Costotransverse joint
Transverse processes contain costal facets for the tubercle of the ribs except on
T11 and T12
Vertebral bodies contain two semi-facets for the head of the ribs except
T10, T11 and T12
They only have one facet
Movement of the thoracic region is limited due to two factors
- Attachment of the semi-rigid rib cage, protecting the thoracic organs
- The shingle-like position of the long spinous process
Lumbar vertebrae (5)
Largest and strongest vertebrae
Spinous processes are short and thick
Spinous processes are quadrangular and project straight posteriorly
One of the most moveable regions of the spine
The sacrum (5 fused sacral vertebrae)
Triangular in shape located between the hip bones
Strong foundation for the pelvic girdle
Sacrum fusion timeline
Starts at 16-18, finalizing by 30
Women’s sacrum are…
Shorter, wider and more curved
Sacrum curvatures
Anterior aspect is concave
Posterior aspect is convex
Sacrum foramina
Anterior sacral foramina (4)
Posterior sacral foramina (4)
Communicate with the sacral canal and allow for passage of nerves and blood vessels
Sacral promontory
Anteriorly projecting border of the broad superior portion (base of sacrum)
Sacral hiatus
Inferior entrance of the sacral canal
Sacral crests
Median sacral crest (1)
Lateral sacral crests (2)
Articular surfaces of the sacrum
Contained on the lateral surfaces, form the sacroiliac (SI) joint with the hip bone
Sacral tuberosity
Posterior to the articular surfaces for the attachment of ligaments
Coccyx
3-5 fused coccygeal vertebrae
Triangular shape
Coccygeal vertebrae fuse around age…
20-30
Coccyx articulates superiorly with…
Apex of the sacrum
Coccyx points…
Inferiorly in females
Anteriorly in males
Thorax consist of
The sternum
12 pairs of ribs
12 thoracic vertebrae
The sternum consists of
Manubrium
Body
Xiphoid process
Sternal angle
Junction of the manubrium and the body of the sternum
The sternal angle is a landmark for…
Site of attachment of the 2nd rib
The suprasternal (jugular) notch is a landmark for…
Palpation of the trachea
The xiphoid process is a landmark for…
Attachment of the 7th rib
Subcostal angle
Sternum provides attachment to…
The clavicles
The ribs
Muscles of the neck, thorax and abdomen
Xiphoid process ossifies around age…
40
Ribs increase progressively in length from…
1st to 7th
Ribs decrease progressively in size from…
8th to 12th
Costal cartilage
Hyaline cartilage on the anterior end of each rib
True ribs
Ribs 1-7
Attach directly to the sternum via sternocostal joints (synovial)
False ribs
8-12
Either attach indirectly or do not attach to the sternum
All ribs articulate with…
Their corresponding thoracic vertebrae
Vertebrosternal ribs
True ribs
Vertebrochondral ribs
False ribs
Floating ribs
11 & 12, do not attach to the sternum at all
Costal margin
Cartilage of 8th, 9th & 10th ribs attach one another and joint cartilage of the 7th rib
Subcostal angle
Where the two costal margins meet at the xiphoid process
Measuring the subcostal angle may help…
Define the body type of an individual
Mesomorphic
Subcostal angle is 90 degrees
Ectomorphic
Subcostal angle is more that 90 degrees
Endomorphic
Subcostal angle is less than 90 degrees
