Anatomy of Thoracic Spine Flashcards
What is the second least mobile of the spine regions?
Thoracic spine
Sacrum is the least mobile
what is the introvertebral disc height to vertebral body height ratio?
1:5
This is said to account for a decrease in mobility
The height of the body is slightly higher…
posteriorly
This contributes to normal kyphosis
Each body has paired costal facet posterolaterally superior and inferior except
T10, 11, 12
superior demifacets are located…. and articulates with
at the root of the pedicle
Articulates with the numerically corresponding rib
(transverse process articulates with the tubercle of the same number rib as well)
inferior Demi facets are located… and articulates with
located just anterior to the vertebral notch
Articulates with the rib below
The pedicles protrude
directly posterior
lamina osteology
Higher and wider and overlap like tiles on a roof
Limit extension
superior facet osteology
Slightly convex
posteriorly oriented 60° from the horizontal plane
20° from the frontal plane
Inferior facet osteology
slightly concave
Face anteriorly
Slightly inferiorly and medially to match the superior facets of the vertebrae below
transverse processes osteology
project laterally and slightly posteriorly
Spread laterally diminishes from T1 to T12- Start to resemble L1
Oval facet located anterior at the tip for articulation with tubercles of numerically corresponding ribs
spinous processes osteology
Project posteriorly, and inferiorly
Remember rule of threes
Rule of threes
vertebra- spinous process level
T1-T3 -same level
T4 - T6 - half a level below
T7 - T9 - one whole level below
T10- one whole level below
T 11 - half a level below
T12- same level
True ribs
Vertebrosternal
first seven pairs of ribs
Connects to the sternum by their costal cartilages
false Ribs
vertebrocostal
Last five pairs of ribs
Costal cartilages of 8,9,10 ribs are joined to cartilages ribs above
floating ribs
vertebral
11 and 12
Ribs osteology: anterior end and shaft
anterior end- Small cup shaped depression for costal cartilages
shaft- outward convexity with costal groove on under surface for intercostal, nerves and vessels
Posterior angle of rib
bend in shaft about 2 inches from the tubercle
posterior end includes
Head
Neck
Tubercle
articular facets for the facet of the vertebra above and below
Crest of the head for the radiate ligament connect to the intervertebral disc
facet on the tubercle for the transverse process of vertebra
Non-Articular process for attachment of the costal ligaments
at each level, there are how many joints?
6
arrangement of facet joints allow for
Flexion- upward gliding
Extension- downward gliding
Rotation - sideways gliding
Costovertebral joint structure
Synovial Joint
formed between heads of ribs and thoracic vertebral bodies
Interposed IVD
1st, 10th, 11th and 12th ribs articulate with a single vertebral body
costotransverse structure
upper joints are convex/concave
lower joints are planar
This accounts for
Spin (rotation) of ribs within the upper T spine
Slide (elevation, depression) of ribs within the lower T spine
Upper ribs movement
pump handle
Rotation , spin
lower ribs movement
Bucket handles
Slide , elevation, depression
Costochondral junction
costal Cartlidge fits into the depression in the distal end of each rib
Secured by enveloping periosteum, which is continuous with perichondrium
Can be site of primary sprains or irritation or secondary pain caused by rib cage dysfunction
neural arch ligaments
Ligamentum flavum
Interspinous ligament
Supraspinous ligament
intertransverse ligamen
Grade together at their boundaries to unite and function as a single unit
Capsular ligaments
represents a bridge between the neural arch ligaments, and those of the vertebral body
Capsule reinforced dorsally by multifidus and ventrally by ligamentum flavum
Ventral ligaments
ALL
PLL
vertebral body ligaments
deep muscles of the back
intertransversarii- covers the intertransverse ligaments
levatores costarum- meant to lift the ribs
rotatores thoracis
Most centrally placed muscles
spinalis thoracis
longissimus thoracis
iliocostalis thoracis
multifidus
semispinalis thoracis
serratus anterior
Long thoracic Nerve
external intercostal
muscular posteriorly
membranous anteriorly
fibers run anteriorly and inferiorly
internal intercostals
muscular anteriorly
membranous posteriorly
fibers run inferiorly and posteriorly
innermost intercostals
membranous anteriorly and posteriorly
muscular in the midsection
fibers run same as internal intercostal
inferiorly and posteriorly
serratus posterior superior and inferior
innervated ventral primary rami
Not innervated by dorsal primary rami
erector spinae
live between angles of the ribs
innervated by posterior primary rami
