Atlanto-Occipital & Atlanto-Axial & Occipito-Axial Joints Flashcards
classification of the atlanto-occipital joint
synovial (diarthrosis) ellipsoidal
other joint space that the atlanto-occipital joint will communicate with
posterior bursa of the median atlanto-axial joint
classic function of the anterior atlanto-occipital ligament
brakes or limits “extension” of the skull over the cervical spine
ossification of the free margin of the posterior atlanto-occipital ligament results in which atypical bone classification
accessory bone
other name that may be used to ID a ponticulus posticus
Kimmerle’s anomaly
names given to the opening formed by the ponticulus posticus
arcuate foramen or retroarticular canal
classic function of the posterior atlanto-occipital joint
brakes or limits axial rotation, flexion, and perhaps lateral bending of the skull on atlas
amount of flexion-extension that is accommodated by the atlanto-occipital joint
~25*
amount of axial rotation that is accommodated by the atlanto-occipital joint
~3-8* one side axial rotation
amount of lateral bending accommodated by the atlanto-occipital joint
~5*
motion is best accommodated by the atlanto-occipital joint
flexion-extension
which atlanto-axial joint is ID’ed as a synovial plane
lateral atlanto-axial joint
which atlanto-axial joint is ID’ed as a synovial pivot
median atlanto-axial joint
names given to the synovial joint spaces of the median atlanto-axial joint
anterior bursa and the posterior bursa
function of the transverse atlantal ligament
it is the primary stabalizer of the atlanto-axial joint restricting the distance of C2 from the anterior arch of C1
what is ADI
Atlanto-Dental Interspace, a radiographic distance between the surfaces of the anterior bursa of the median atlanto-axial joint
ADI is observed between which surfaces
fovea dentis of C1 and the facet for fovea dentis of C2
ADI of children vs adults
children = 4.5 mm adults = 2-3 mm or about 2.5 mm
attachment sites for the accessory atlanto-axial ligament
base of the odontoid process and vertebral body of axis to the tubercle for the transverse atlantal ligament on the lateral mass of C1
a superior continuation may attach on the occipital bone just behind that of the alar ligament
degrees of movement facilitated at the atlanto-axial joint
20* flexion-extension
40* one side axial rotation
5*lateral bending
occiput-C1-C2 joint complex accounts for what percent of all cervical axial rotation
~60%
ligament that attaches to the anterior margin of the foramen magnum and the tip of the odontoid process of C2
apical ligament of the dens or the apicodental ligament
the embryonic derivative of the apical ligament of the dens or the apicodental ligament
notochord
function of the alar ligament
together they function to resist axial rotation
forms the cranial continuation of the PLL
membrana tectoria or tectorial membrane
attachement sites for the superficial layer of the membrana tectoria
posterior part of the inferior epiphyseal rim and vertebral body of C2 to the capsular ligament of the atlanto-occipital joint and cranial dura of the posterior cranial fossa
list, in order, ligaments in the midsagittal plane from the dura mater at the level of the medulla oblongata to the anterior bursa of the median atlanto-axial joint
membrana tectoria
cruciate ligament
capsular ligament of the posterior bursa of the median atlanto-axial joint
apical ligament of the dens
for cervical spine below C2, what is the range of flexion-extension
~90* or 18* per couple
for cervical spine below C2, what is the range of one side lateral bending
~50* or 10* per couple
for cervical spine below C2, what is the range one side axial rotation
~33* or 6* per couple
