Spine

Question 1

Typical vertebra

Answer 1

Body
Arch - 2 pedicles, 2 laminae
Processes (7) - 1 spinous, 2 transverse, 4 artic (2 sup 2inf from junctions pedicels and lamina)

Question 2

Atypical cervical

Answer 2

C1 atlas - no body, no SP, anterior and posterior arches, widest of cervical
C2 axis - has dens, held to C1 by transverse, superior artic facet on body not transverse process
C7 - no foramina in transverse processes, non bifid spinous

Question 3

Atypical thoracic

Answer 3

T1 - sup facet not demi (inf demi)
T9 - no inf demifacet
T10 - single pair of costal facets on body an pedicle
T11+2 - single pair of costal facets on pedicle - no transvers process facets

Question 4

Sacrum

Answer 4

5 vertebrae fused
Sacral hiatus - formed from lack of S5 spinous process

Question 5

Vertebral body joints

Answer 5

secondary cartilagenous
ant longitudinal (stops extension) and post longituinal (stops flexion)

Question 6

Zygapophysial joints

Answer 6

plane synovial joint - gliding
from sup and inf facets
More horizontal C, others vert with medial on L
nerve supply - articular branches of medial branches post rami

Question 7

Atlanto-occipital joint

Answer 7

synovial condyloid
From atlas to occipital condyles
allows yes movement
ant (from ant longitudinal)and post atlanto occipital membrane

Question 8

Atlanto-axial joint

Answer 8

medial pivot joint, lateral 2x gliding synovial (3 x artic surfaces)
allows no movement
dens held on with transverese lig around C1, ongitudinal bands (togetehr make cruciate)
alar from dens to foemane magnum to prevent rotation
tectorial membrane from post longitudinal

Question 9

Arterial vertebral column

Answer 9

segmental arteries depending on level
body - periostial to surface, equatorial deeper
anterior vert canal arteries supply red marrow
radicular/ segmental medullary supply cord

Question 10

Venous drainage

Answer 10

intervertebral veins from cord
basivertebral from bodies
join int and ext plexi

Question 11

Extrinsic back muscles

Answer 11

connect axial and appendicular
all ant rami except trap (XI)
superficial - trapezius, lat dorsi, rhomboids, levator scapulae
intermediate - serratus posterior

Question 12

Intrinsic back muscles

Answer 12

proprioception and extnsion innervated post rami
superficial - splenious
intermediate - erector spinae
deep - transversospinalis

Question 13

Ligamentum flavum

Answer 13

lamina to lamina, resist flexion

Question 14

Meninges

Answer 14

Dura - outer thick, makes dural sac
Arachnoid - avascular, held against dura by CSF, trabeculae connecct to pia
Pia - becomes fillum terminale, suspends cord through filum and la denticulate ligs

Question 15

Epidural and subarach

Answer 15

Epidural - fatty, internal vertebral venous plexus, pinal nerves below L2
Subarachnoid - between arachnoid and pia, CSF, arteries + veins: raicular, segmental, medullary and spinal
Lumbar cistern L2-S2

Question 16

Spinal cord arteries

Answer 16

2x post
1x ant from segmental - occlusion lose all except vibration and proprioception
medullary arteries formed around brachial and lumbrosacral plexi
medulary supplies nerve roots / radicular if not present
venous - 3 ant 3 post

Question 17

Layers you go through LP

Answer 17

Skin
Sub cut CT
Supraspinous ligament
Interspinous ligament
Ligamentum flavum
Dura mater
Arachnoid mater