Spine Anatomy Flashcards
Uncovertebral joints
AKA Joints of Luschka; ucinated processes C3-T1
- lateral/superior surface of inferior vertebrae and inferolateral surface of superior vertebrae
- Develop w/in first 12 years life, fully developed by 33
- Guides cervical F/E, reduces SB of c-spine, prevents posterior translation of neighboring vertebrae, reinforces posterolateral aspect of IVD
- *Impairments of uncovertebral joints unaffected by F/E
Tectorial Membrane:
- Connects occipital bone to C2
- superior continuation of PLL
- Important limiter in upper cervical flexion; holds occiput to atlas
Alar Ligament:
- dens to medial occipital condyles
- resists flexion, C/L SB, and C/L OA rotation
- *Insufficiency increases OA instability
Cervical spine Transverse Ligament:
- part of cruciform ligament
- connects C1 to Dens
- limits flexion b/t C1 and C2
ALL
C-spine: Narrower in upper c-spine, wider in lower c-spine; firmly attached to inferior end plates but NOT to IVD; restricts extension
PLL
C-Spine: up to C2 where it is continuous with tectorial membrane; prevents disk protrusions, restrains segmental flexion
*Broader and thicker in c-spine than thoracic/lumbar
Ligamentum Nuchae:
External occipital protuberance fo C7 SP
-When OA joint flexed, tightens and pulls on deep laminae and muscular attachments AKA limits anterior translation in flexion
Dysfunction with shortened Rectus Capitus Anterior muscle on R
Decreased L translation in extension at OA
Suboccipital muscles:
RCP Major, RCP minor, Obliques inferior, Obliques superior -Innervated by posterior ramus C1 Strongly linked to trigeminal nerve b-supply from vertebral artery -RCP Major and OCI: I/L rotate head -RCP Major and Minor: extend head -OCS: I/L SB
Scalenes:
Anterior: C3-C6 TPs–>1st rib
Middle: C2-C7 TPs–> 1st rib
Posterior: C4-C6 TPs–>2nd rib
Ant & Middle: if neck fixed elevates first rib; if rib fixed I/L SB and C/L rotation
Post: if neck fixed elevates 2nd rib; if rib fixed I/L SBs
What muscle does the greater occipital nerve (C2) pierce through?
Semispinalis Cervicis
Where do nerves exit?
C-spine: ABOVE level (C1-2) = C2
t-spine: BELOW level (T1-T2)= T1
OA joint motion:
F/E
*Hypermobility considered if axial rotation >8 deg here
AA joint motion
rotation
–To decrease compression of vert A as rotating, I/L C1 facet moves posteriorly while C/L facet moves anteriorly (each move inferiorly)
C-spine Arthrokinematics for F/E, rotation, SB
Flexion: Superior lateral glide of IAP of superior vertebra
Ext: inferior medial glide of IAP of superior vertebra
Rotation: I/L extension (closing), C/L flexion
SB: I/L extension (closing), C/L flexion (opening)
C-spine flexion: 3 sequential phases
Initially at C4-7 (most at C6-7)
2nd at C0-2
last at C2-3, C3-4
C-spine facet orientation, innervation, and % load bearing
45 deg to sagittal
- innervated by dorsal rami
- bear 9-25% load; if spine arthritic facets may bear 50% of load
C spine motions at upper, middle, and lower segments
C0-1: 10-15 deg F/E, 8 deg SB; minimal rotation
C1-2: 10 deg F/E; 45 deg rotation; minimal/no SB
C3-7: 64 deg F 24 deg E; 40 deg SB and rotation
T Spine AROM
Flexion: 6 deg
Extension: 20 deg
SB: 20-24 deg each direction
T spine facet orientation
60 deg inclination from sagittal and 20 deg from frontal planes
Disc ratios in cervical vs thoracic vs lumbar spine
Cervical: 2:5
thoracic: 1:5
Lumbar 1:3
Rib TP connections vs v.body connections
Ribs 1-10 attach corresponding TP
Ribs 11-12 no costotransverse joints
Ribs 1, 10, 11, 12 attach to corresponding v. body only
Rib 2 attaches t T1-2, manubrium and sternum
Ribs 3-9 have superior and inferior facets that attach to superior and inferior T-spine bodies
thoracic biomechanics: SB, with UE elevation
–SB: I/L translation of superior segment on inferior
With UE elevation, T-spine extends, rotates, and SB to I/L side
Thoracic biomechanics: rotation
Greatest at upper T-spine, decreases with lower t-spine
- Slight C/L glide of superior segment
- Ribs: posterior rotation of I/L, anterior rotation of C/L
Inspiration/expiration ribs movements
- Ribs 1-10 inspiration: lateral and superior glide (pump handle) sagittal plane elevation
- Ribs 11-12 caliper motion (bucket handle) frontal plane flaring
Serratus Anterior influence on ribs when scapula fixed
Will pull ribs posteriorly
Pec major action on ribs when humerus fixed and flexed
pulls rib cage anteriorly, superiorly and laterally
What happens with shortening/hypertonicity of pec minor
protraction and anterior tipping of scapula
External intercostals vs internal intercostals
EI: direction superoposterior–>inferoanterior; pulls lower rib towards upper rib (results in inspiration)
II: inferoposterior–>superoanterior; deep to and runs obliquely to EI; during forced expiration pulls upper rib down on lower rib
Muscles of forced expiration
-Primary: Internal and external obliques RA TrA internal intercostals (posterior) transversus thoracics transversus intercostals -Secondary: Lats, Serr Post, QL, iliocostalis lumborum
Muscles of inspiration
-Primary: Diaphragm, levator costorum external intercostals internal intercostals (anterior) -Accessory: Scalenes, SCM, traps, SA, SP, pec major and minor, lats, subclavius
Where does subcostal nerve supply sensory innervation to ? What can happen and cause pain?
Supplies abdominal wall skin, lateral hip region, and over iliac crest
Dysfunction of TL junction can cause pain in hip region
T-spine biomechanics: flexion
F: IAP of superior vert glides superior and anterior on SAP of inferior
- *Results in concomitant forward rotation of rib head at costovertebral joint
- *Concave rib tubercle glides superiorly on convex facet on TP at costotransverse joint
- Initiated by abdominals and continued by gravity (if unresisted) with e-spinae eccentrically controlling
- Can also occur due to (B) scapular protraction
t-spine biomechanics: extension
IAP of superior vert glides inferior and posterior on SAP of inferior vert
- *Concomitant posterior rotation of rib head at costovertebral joint
- *Concave rib tubercle glides inferiorly on convex facet on TP at costotransverse joint
t-spine biomechanics: Side bending
- I/L IAP of superior vert glides inferolaterally and C/L IAP glides superomedially
- I/L ribs approximate
- C/L ribs seperate
- -Gradually increases from T1-T12
Lumbar neurodynamics
with forward being, movement at L1-L3 roots only
-With SLR greater lumbar nerve movement at lower levels
positions for optimal disc nutrition
80% disc nutrition absorbed during 1st hr
- Sidelying or supine optimizes nutrition
- prone not recommended unless pillow under abdomen
lumbar disc innervation:
Sinuvertebral nerve and gray ramus communicans from sympathetic chain
