Cervical spine arthrology upper and lower Flashcards
Cervical Intervertebral Disc size
Relatively small
Transversely broad
where are there no IV-disc in the c-spine
No disc between A/O and A/A joints
the joint that the Intervertebral Disc creates
Forms symphysis between 2 vertebral bodies
Nucleus Pulposus in the c-spine
Constitutes less than 25% of disc volume at birth (lumbar about 50%)
Gel-like until adolescence – becomes fibrous at about 20 yrs of age
Penetrated by uncovertebral clefts
Annulus Fibrosis anterior portion c-spine
Fibers interweave & have angled orientation
No separate laminae
Annulus Fibrosis posterior portion c-spine
Smaller posterior portion
Fibers oriented vertically
Annulus Fibrosis posterior-lateral portion c-spine
Lacking posterolaterally where uncovertebral jts are located
Annulus Fibrosis anterior properties
Anterior annulus fibrosis is major stabilizer in cervical spine
Can be torn with whiplash injuries
Annulus fibrous innervation
Outer 1/3 of annulus fibrosis has sensory innervation
Can be a source of pain
(all AF have sensory innervation)
Uncovertebral Joints other name
Joints of VonLuschka
Uncovertebral Joints are what kind of joint
Synovial jts
location of Uncovertebral Joints
between uncinate processes of vertebra below and body of vertebra above
Uncovertebral Joints bordered by
Bounded anteromedially by IV disc, & posterolaterally by IVF
Uncovertebral Joints and arthritic changes
can impact the intervertebral foreman - Can impact the spinal nerve traveling through the intervertebral foramen
Uncovertebral clefts
Cleft can be thought at continuation of the uncovertebral space into the disc
- These clefts can complete transect the posterior portion of the disc and if they do – this allows for more movement into the rotation at the interverbal disc
Intervertebral Joint are like what kind of joint
Resemble saddle joints
included Symphysis & U/V jts
Intervertebral Joint Movement types
Flexion/Extension in sagittal plane
Lateral flexion coupled with (isp) rotation in plane of facet jts
Intervertebral Joint Movement - Flexion/Extension in sagittal plane
Narrow Anterior/posterior dimension of disc allows greater sagittal plane motion
Uncovertebral joints guide sagittal plane motion
Intervertebral Joint Movement - Lateral flexion coupled with rotation in plane of facet jts
Broad transverse dimension of disc allows for limited lateral flexion
Uncinate processes provide lateral stability by limiting lat flexion
Typical Cervical Facet Joints
C2/3-C6/7
Typical Cervical Facet Joints types of joints
Synovial joints
Typical Cervical Facet Joints orientation
Orientation in oblique plane (roof shingles)
Inferior articular facets
Slightly concave
Face inf’ly & ant’ly
Superior articular facets
Slightly convex
Face sup’ly & post’ly
Facet orientation in the c-spine allow for what kind of motion
facilitates sagittal plane motion and requires that axial rotation and lateral flexion are always coupled
Facet Orientation also provides for
some weight-bearing capability
impediment to forward translation
Typical Cervical Facet Joints - joint capsule
Enveloped in baggy capsules which are lax in neutral position and taut in extremes of motion
intra-articular inclusions in the c-spine
Fat pads, fibroadipose menisci
Anterior longitudinal ligament runs to
the occiput
ALL function
Reinforce interver-tebral joints
ALL and pain fibers
Heavily innervated with pain fibers
ALL and cervical discs
May or may not have attachments into cervical discs
Longitudinal Ligaments extends to
Extends only to posterior body of C2
Posterior longitudinal ligament changes into the
Tectorial membrane is cranial extension of PLL
Ligamentum Flavum found between
connect the laminae of adjacent vertebrae
Ligamentum Flavum extend to
Extends to C1/2
Ligamentum Flavum made out of
elastic fibers
vertebral canal and the Ligamentum Flavum
Provides smooth post wall for vertebral canal
Ligamentum Flavum and movement
Too distensible to limit movement
Accommodates large changes in intralaminar distance with flexion/extension
what is the Ligamentum Nuchae
In the cervical region, homologous to interspinous and supraspinous ligaments
Ligamentum Nuchae two parts
midline raphe and midline fascial septum
midline raphe
for origins of upper trapezius, splenius capitis, & rhomboid minor
midline fascial septum
separates semispinalis capitis
Movement in Lower Cervical Segments is determined by
by orientation of facets
facet joints what kind of joint surface
planar -synoivial joints
Sagittal Plane Motion - felxion, movement seen
Both upper facets move sup’ly & ant’ly on lower facets
Sagittal Plane Motion - felxion, movement limited by
Limited by tension in PLL, artic capsule & ligamentum nuchae
In full flexion what does facet contact look like
minimal facetal contact - opening-up
Sagittal Plane Motion - extension, movement seen
Both upper facets move inf’ly & post’ly
In full extension what does facet contact look like
Facetal approximation - closing down
Sagittal Plane Motion - extension, movement limited by
Limited by tension in ALL and impact of SPs, and sup articular processes of vertebra below with TPs of vertebra above
what side do Combined Lateral Flexion with Rotation occur on
Both occur to same side
example Combined Lateral Flexion with Rotation to the right
Right upper facet glides inferiorly and posteriorly (closing down)
Left upper facet glides superiorly and anteriorly (opening up)
two Upper Cervical Joints
Atlanto-Occipital Joints
Atlanto-Axial Joints
Lateral atlanto-axial joints
Median atlanto-axial joint
Atlanto-Occipital (A/O) Jointswhat kind of jt
Synovial ellipsoid jts
Atlantal facets properties
Concave, tilted medially
Constricted in middle
Long axes run obliquely ant & med
Occipital condyles
convex
Ligaments of A/O Joints
Fibrous capsule
Anterior Atlanto-Occipital Membrane
Posterior Atlanto-Occipital Membrane
Fibrous capsule of A/O joint
Thickened posterolaterally
Thin & sometimes lacking medially where joint may communicate with bursa between dens & transverse ligament
Anterior Atlanto-Occipital Membrane
Broad, dense membrane between foramen magnum and anterior arch of atlas
Strengthened by ALL
Posterior Atlanto-Occipital Membrane
Broad, thin membrane between foramen magnum & posterior arch of atlas
Arches over groove for vertebral artery forming opening for artery
Movement at A/O Joints
The two joints act as one
Movement may occur around transverse axis (nodding), and A/P axis (slight lateral flexion)
Flexion – nodding at the A/O joint
Occipital condyles roll ant’ly & glide post’ly
About 10-degree range
Extension at the A/O joint
Occipital condyles roll post’ly & glide ant’ly
About 25-degree range
Lateral flexion
Ipsilateral occipital condyle glides ant’ly, med’ly & inf’ly
Contralateral occipital condyle glides post’ly, lat’ly & sup’ly
So some conjunct rotation occurs to opposite side
About 5 deg range
Lateral Atlanto-Axial Joints formed by
Articulations between:
inferior articular surface of thelateral mass of atlas(C1) - the superior articular surface of thelateral mass of axis(C2)
Lateral Atlanto-Axial Joints what kind of joint
Synovial joints
Lateral Atlanto-Axial Joints capsule type
Capsules are thin & loose
Lateral Atlanto-Axial Joints facet shapes
Facet surface shapes are debatable
The kinematic remain the same
Median Atlanto-Axial Joint
between dens & ring formed by ant arch of atlas & transverse ligament
Median Atlanto-Axial Joint type of joint
Synovial pivot joint
Median Atlanto-Axial Joint anterior
Ant’ly, capsule encloses space bet ant arch & dens
Median Atlanto-Axial Joint posteriorly
Post’ly, larger synovial cavity lies between transverse ligament & dens
what is the Transverse Ligament
Thick strong band dividing ring of atlas into 2 unequal parts
Transverse Ligament attaches to
Attached on each side to tubercle on lateral mass
median portion of the transverse ligament
Median portion lined with cartilage for articulation with dens
Transverse Ligament function
Function: Retains dens in contact with anterior arch of atlas during movement
cruciform ligament
cross
made out of the:
transverse ligament
small band - extends up to the O (
large band - extends down to the body of the axis (sometimes absent)
where does the small band of the cruciform liagment lie
lies between tectorial membrane & apical ligament
Movement at A/A Joints in general
Occurs simultaneously at all 3 joints
Lateral joints support weight of head via atlas, while medial joint guides rotation
Consists primarily of rotation with minimal degree of flexion/extension
Rotation at A/A Joints dens momvement
During rotation dens should not move, but act as pivot around which movement occurs
facet movement with Rotation at A/A Joints
Inferior facet of atlas glides forward with contralateral rotation and backward with ipsilateral rotation (reform)
rotation at the A/A joint is limited by what
Limited by alar ligs
range of Rotation at A/A Joints
Total range: ~45 degrees
- 20ish on each side
Flexion/Extension at A/A Jts - during flexion
inferior facets of atlas roll ant’ly & glide post’ly
Anterior arch of atlas glides inf’ly
Flexion/Extension at A/A Jts -During extension
inferior facets of atlas roll post’ly & glide ant’ly
ant arch glides sup’ly
Flexion/Extension at A/A Jts - dens movement
Regardless of the facet surface shapes, the dens will retain contact with the anterior arch of the atlas and the atlanto-odontoid interval will not open out
Transverse Ligament is keeping dens in place
range of motion during Flexion/Extension at A/A Jts
10 degrees of movement
Ligaments Connecting Axis and Occipital Bone
Tectorial Membrane
Alar Ligaments
Apical Ligament
Tectorial Membrane
Lies within vertebral canal
Extension of PLL
Broad, strong
Runs from body of axis to occipital bone in front of foramen magnum
Alar Ligaments
2 strong cords run from dens obliquely up and lat’ly to condyles of occiput
Alar Ligaments resitriction of movement
Primary restraints- for contralateral rotation & lateral flexion
2ndary restraint for flexion
alar ligament are most taut with
Flexion
Extension combined with rotation
Apical Ligament of Dens
Runs from tip of dens to anterior margin of foramen magnum
Very thin
More reinforcement
Apical Ligament of Dens lie where
Lies between upper band of cruciform ligament & anterior atlanto-occipital membrane
