Lecture 1: Cervical Spine Functional Anatomy Flashcards
What are components of upper cervical spine?
occipito atlantal joint, atlanto axial joint
What are primary motions of OA jt?
occipital condyles and C1 atlas
flexion and extension 25-30 degrees
SB 10 degrees
What is arthrokinematics of OA jt?
flexion of head- occiput slides posterior
extension- occiput slides anterior
What is primary motion of the AA joint?
rotation 45-60 degrees odontoid process of C2 acts as a pivot for rotation
What is helpful radiographic view for AA joint?
odontoid view helpful to r/o fx
What are two important ligaments in the upper cervical spine?
transverse ligament, alar ligament
Where is the transverse ligament located?
between medial aspects of lateral masses of atlas
prevent anterior translation of c1 on c2
What are two kinds of transverse ligament classification?
caused from trauma
type 1- disruption of the ligament without an osseous component
type 2- fracture or avulsion involving the tubercle for insertion of the ligament on the C1 lateral mass, without disruption of the substance of the ligament
What are 3 types of causes of AA instability?
- congenital- os odontoideum ( separation of dens from atlas)
- arthritis- RA, psoriatic arthritis, Reiter syndrome, AS, SLE
- acquired- trauma/fx, abcess, recurrent URI
What is the Atlas Dens interval (ADI)?
is the horizontal distance between the anterior arch of the atlas and the dens of the axis,
should be no more than 2.5 mm
What happens during anterior subluxation of C1 on C2?
spinal cord is compressed between the pannus anteriorly and posterior arch of atlas
common in pts with AS
What are attachments of alar ligament?
connects odontoid process to occipital condyles
prevents excessive rotation and SB
What are characteristics of vert of c2-t3?
contain articular pillar of facet joints, SC passes through vertebral arch
What is midpoint of cervical lordosis?
c4-5 interspace
What are the uncovertebral joints?
guide flexion and extension, limit SB, reinforce the intervertebral disc
What are primary ligaments of cervical spine?
- anterior longitudinal- taut in extension
- posterior long.- taut in flexion
- interspinous and supraspinous- taut in flexion
- ligamentum flavum- continous with joint capsule
What is mobile/functional unit of cervical spine?
2 adjacent vertebrase the IVD, facet joints and ligamentous structures
each mobile unit has 2 facet joints
ex: if its C6 it includes C7 named by superior vert.
What is Fryette’s law?
movement patterns for the spine- if movement in one plane introduced to the spine, any motion in another direction is restricted
What is an example of Fryette’s law?
if you fully flex it will be hard to side bend or rotate
however this is good as it can isolate AA joint
same with AO if you rotate and flex
What is coupled cervical spinal motion for upper cervical spine (above c2)?
SB and rotation takes place to opposite sides regardless if vert are in flexion or ext.
What is coupled cervical spinal motion for lower cervical spine (c2-t3)?
rotation and SB to same side
What are two ways to document facet joint movement?
- motion restriction- right facet cant downglide or close
2. positional fault- the right facet is flexed, rotated left or sidebent left
