Spine Flashcards
What are the three purposes of the spine?
protection, stability, mobility
How many degrees of motion in spine mobility?
3
What forces does the spine provide stability against?
tension, compression, bending, twisting
Neuromobility
-sliding/gliding and tensioning/slacking can happen
-nerves CAN’T stretch
**chain link fence
What does anterior column consist of?
vertebrae, intervertebral discs
What does posterior column consist of?
bony rings, facets, and foramen
Purpose of vertebral foramen
-creates spinal canal which houses spinal cord (central nerves)
Purpose of intervertebral foramen
houses the nerve roots (PN)
Spinal regions
-cervical: C1-C7
-thoracic: T1-T12
-lumbar: L1-L5
-sacrum: 5 fused
-coccyx: 4 fused
Sagittal plane development
-C spine lordosis develops w/ head lift
-L spine lordosis develops w/ sitting
Cervical vertebrae (C3-C7)characteristics
-vertebral bodies have joints of Luschka
-transverse processes have vertebral artery foramen
-bifid spinous process
-facet planes on an 30-45 degree, oblique plane
Typical cervical vertebrae characteristics
-shorter spinous process
-large and triangular vertebral foramen
-superior and inferior facets
Thoracic vertebrae characteristics
-triangular body shape
-vertebral foramen- relatively small
-transverse processes - swept posteriorly
-articular facets for ribs
-spinous process (long and swept inferiorly)
-facet planes more vertically inclined
Thoracic spine rule
T1-T3 SP and TP same level
T4-T6 SP 1/2 level below TP
T7-T9 SP full level below TP
T10 full level below
T11 1/2 level below
T12 same level
Purpose of cervical, thoracic, and lumbar
-cervical: mobility
-thoracic: stability/protection
-lumbar: stability
Lumbar vertebrae characteristics
-large body
-transverse and spinous processes: thick and broad
-large discs for WB
-facet planes
What does a spinal segment consist of?
-adjacent halves of two vertebrae
-disc
-contents of vertebral and intervertebral foramen
-facets
-associated ligaments, muscle, fascia
What does the disc (anterior joint) consist of?
-annulus fibrosis
-nucleus pulposis (rich w/ proteoglycans)
-vertebral end plates
What are facet joints created by?
inferior articular process of superior vertebra, superior articular process of inferior vertebra
What are joints of luschka?
C3-C6
-allows WB force transmission across anterior elements
-allows flex/ext tracking
What type of load do facet joints bear? How much?
Compressive load; 30%
What type of load do intervertebral discs bear? How much?
Shear and torsional loads; 70%
What muscles are in the anterior chain?
Longus colli and psoas
What muscles are in the posterior chain?
Paraspinals, glutes, and hs
Which muscles are the movers?
Erector spinae, rectus abdominus, obliques, glute max, hs
Which muscles are stabilizers?
Multifidus, rotators, pelvic floor, diaphragm, TVA
Ilial motions in relation to sacrum
Rotations, out/inflare, up/down slips
Sacral motions
Flex/ext, rotations
Pubic motion
Upslip
What are the functions of the sub-cranial region?
-supports the head on the spine
-encases and protects neural elements
-allows for quick motions and reflexive balance and righting rxns
What is C1 and C2?
C1 - Atlas
C2 - Axis
Characteristics of C1
-no vertebral body
-large superior facets
-articulates w/ dens from C2 to allow large range of rotation
Characteristics of C2
-dens projects from body into C1 ring
-dens is anterior superior to spinal cord and is where head rotation occurs
What motions occur at occiput-C1 and C1-C2?
Occiput-C1 = flex/ext, SB
C1-C2 = rotation of 1/2 cervical motion
Occipital-Atlanta (OA) joint
-2 articulations
-atlas and occipital
-allows flex/ext
Articulations and motion of Atlanta-Axial (AA) joint
-3 articulations (2 lateral between inferior and superior facets C1 and C2, 1 median between dens and anterior arch of atlas)
-side to side head turns
Fryette’s First Law
When the spine is in neutral, SB-ing to one side will be accompanied by rotation to the opposite side
Fryette’s Second Law
When the spine is in a flex/ext position, SB-ing to one side will be accompanied by rotation to the SAME side
Fryette’s Third Law
When motion is introduced in one plane it will modify/reduce motion in the other two planes
Fryette’s Laws regarding cervical
Not relevant b/c in c/s SB-ing and rotation always occur to SAME side
Facet open/close: lumbar/thoracic
SB R = R closes/L opens
SB L = L closes/R opens
Flex = both open
Ext = both close
Rot R = R opens/L closes
Rot L = L opens/R closes
Facet open/close: cervical
SB R/Rot R = R closes
SB L/Rot L = L closes
Flex = both open
Ext = both close
