Back Osteology Flashcards
Regions of the temporal bone
Squamous
Petrous
Mastoid (includes styloid process/mandibular fossa)
Tympanic
Regions of occipital bone
Squamous part (external)- includes superior/inferior nuchal line Squamous part (internal) Internal/external basilar part
Pharyngeal tubercle of external basilar portion of occipital bone- what muscle inserts here
Superior pharyngeal constrictor muscle
Occipital condyle articulates with
Superior articulating process of the Atlas
Posterior arch of atlas contains
Groove for vertebral artery Posterior tubercle (analogous to spinous process)
Features of lateral mass of the Atlas
Tubercle for transverse ligament (origin/contralateral insertion of transverse band of cruciform ligament)
Superior articulating process (for occipital condyles)
Inferior articulating process (for C2)
Transverse process- transverse foramen for vertebral A.
Jeffersons fracture
Cause by blow to top of the head. Both arches of the atlas are fractured. Typically does not injure spinal cord, but it is possible if the transverse L. is ruptured
Vertebral body of axis contains
Odontoid process aka; dens
Hangmans fracture
Fracture of the vertebral arch of the axis
Caused by hyperextension of head/neck
Odontoid process fracture
Can occur after horizontal blow to head
If it breaks at its base, it will usually not heal because transverse L. is holding it away from blood supply
Vertebral body of typical cervical vertebrae (3-6) contain
Uncinate process
Spina Bifida
Vertebral lamina fail to fuse and close off the vertebral canal
Commonly occurs at L5 and S1
Small patch of hair occurs over the defect
If neural tissue and meninges are involved it is referred to as spina bifida cystica
What is significant about cervical vertebrae spinous processes
They are often bifid
Posterior and anterior tubercles on transverse processes of C1-C6 are attachment for
Posterior: Levator scapulae, scalene and splenius cervicis muscles
Anterior: Longus colli, capitis and scalene muscles
What is the anterior tubercle on C6 also known as
Carotid tubercle
Costotransverse bar
Lateral boundary of transverse foramen
Contains depressed area that accommodates the anterior rami of spinal nerves
Why does it require less force to dislocate cervical vertebrae
Because the articulating facets are more horizontal
However, due to large vertebral foramen, this does not usually result in injury to spinal cord
Vertebral body of thoracic vertebrae
Articulates with the ribs
Superior costal facet- meets with costal head of same segment
Inferior costal facet- meets with costal head one segment up
Spondylosis vs Spondylolysis vs Spondylolisthesis
Spondylosis- calcification of edges of vertebral body
Spondylolysis- Separation of vertebra arch from vertebral body
Spondylolisthesis- Anterior displacement of vertebral body on the inferior vertebral segment
Superior articular facet of ribs
Articulates with inferior costal demifacet on thoracic vertebral body one segment superior
Inferior articular facet of ribs
Articulates with superior costal demifacet on thoracic vertebral body of same segment
Tubercle of ribs
Possesses articular part and non articular part
Articular facet articulates w/transverse costal facet on thoracic vertebrae
Non articular part is attachment point for lateral costotransverse ligament
Costal groove and costal angle on body of ribs
Groove houses intercostal nerve and vessels
Angle is the anterolateral turning point of the rib
Vertebral body of lumbar vertebrae
Very large and kidney shaped
Vertebral foramen of lumbar vertebrae
Transmits spinal cord, conus medullaris and cauda equina
Very large and triangular
Accessory process of lumbar vertebrae
Located on transverse process
Attachment for intertransversarii muscles
Mamillary process
Located on superior articulating process
Attachment for multifidi muscles and intertransversarii muscles
Lumbar spinal stenosis
Narrowing of the lumbar vertebral foramen, may cause compression of spinal nerve roots
Much worse when compounded with intervertebral disc bulging
Lumbar puncture
Performed between L3/L4 or L4/L5 at level of the iliac crests. This level is chosen to avoid injuring the spinal cord
Articular surface or sacrum
Articulates with articular surface of ilium
Hemisacrilization and lumbarization
Hemisacrilization-Partial or complete incorporation of the L5 vertebral segment into the sacrum.
Lumbarization- Separation of the S1 vertebrae from the sacrum
Median sacral crest
Fused spinous processes
Medial (intermediate) sacral crest
Fused articulating processes
Lateral sacral crest
Fused transverse processes
Posterior/dorsal sacral foramina
Smaller than anterior sacral foramina
Transmit posterior ramus of sacral spinal nerves
Sacral hiatus
Gap left by absence of lamina and spinous process of S5
Anterior sacral foramina
Larger
Transmit anterior ramus of sacral spinal nerves
Apex
Articular facet for coccyx
Sacrum is how many fused vertebrae
5
Coccygodynia
Caused by abrupt falls on lower back and difficult child birth that results in bruising/dislocation/fracture of coccyx
Painful and difficult to treat
Primary vs secondary curvatures of vertebral column
Primary- Thoracic and sacral kyphoses
Secondary- Cervical and lumbar lordosis- result from extension from fetal position
Kyphosis vs lordosis vs scoliosis
Kyphosis- exaggerated curving of thoracic vertebrae causing hump back
Lordosis- curving of lumbar vertebrae resulting in sway back
Scoliosis- lateral curving of spine to right or left
