Lecture 3: Axial Skeleton Flashcards
What are the 5 regions of spine
1.Cervical
2. Thoracic
3. Lumbar
4. Sacral
Coccygeal
How many vertebrae in cervical region?
7
How many vertebrae in thoracic region?
12
How many vertebrae in lumbar region?
5
How many vertebrae in sacrum?
1! it is 5 fused together before birth
How can we classify curvatures of spine?
in two ways:
A)
1. primary- present at birth (thoracic, sacral)
2. secondary- not present at birth (cervical, lumbar)
B)
1. Dynamic- can change based on body position (cervical, thoracic, lumbar)
2. Static- can’t change (sacral)
what is the purpose of dynamic curvatures?
INCREASE resistance of vertebral column against compressive forces up to 10 fold!
When does a baby acquire cervical curvature?
when it can hold its head/neck
3 months
when do we acquire lumbar curvature
when begin walking. 18 mnths
Kyphosis
exaggeration of thoracic curvature only
Lordosis
exaggeration of lumbar/cervical curvature
Scoliosis
: side curvature develops in spine or vertebral column
when is scoliosis considered a pathology?
above 5 degrees
btw 5-30= physio
above 30 = surgery
Vertebral foramina
contain CSF
when u stack vertebrae, these foramina form the vertebral canal. in the middle of a typical vertebra
what is the vertebral arch composed of?
- Pedicle: thick piece of bone
- lamina: flat, thin bone
also has bony processes attached on both sides (transverse processe)
Where the two laminae join together = spinous process = palatable for most vertebrae
transverse process articulate with costal tubercle of rib
spinous process
where two laminae join together. can feel this on most vertebrae
articular process
connect adjacent vertebrae
typical vertebrae have superior and inferior articular process
articular facet
smooth concave surface of process
what features does a typical cervical vertebra have?
Bifid spinous process (split in 2)
Transverse forman on transverse process. an artery travels through theseq
Atlas
first cervical vertebra
ATYPICAL
no vertebral body, instead it has an anterior arch
instead of vertebral arch, have a posterior arch
lateral masses where anterior and posterior arches join. on these are articular facets which articulate CI to occipital bone (occipital condyle) and CII
CII
spinous process is almost bifid
has dens: process whicih projects from body of CII superiourly, articulates with atlas
=axis of rotation btw CI and CII
unique features of thoracic vertebrae
spinous process is very long and points inferiourly
unique features of lumbar vertebrae
large body
relatively short spinous process
sacrum
○ 5 bones fused. Remnants of 5 pieces is visible by the transverse ridges (remnants of intervertebral discs which have ossified (turned into bones) no more sign of discs, just horizontal ridges)
○ Body of SI at top, other ridges repesent SII, SIII, SIV, SV
○ Sacral Ala (means wing)- two wings on each side
○ Apex= distal end
○ Superior border of SI is Sacral Promontory (means nose) promotes into pelvic cavity****
§ Promontory is border of SI INTO PELVIC CAVITY
○ Foramina = exit point of spinal nerves. Present in front and back -= ANTERIOR or POSTERIOR SACRAL FORAMINA (depends on view)
