Flashcards in Additional Vertebral Column Arthrology Deck (20):
What is the classification of the atlanto-occipital joint?
synovial (diarthrosis) ellipsoidal
What other joint space does the atlanto-occipital joint communicate with?
the posterior bursa of the median atlanto-axial joint
What is the median thickening of the anterior atlanto-occipital ligament called?
the anterior longitudinal ligament
Ossification of the freee margin of the posterior atlanto-occipital ligament results in which atypical bone classification?
What other name may be used to identify a ponticulus posticus?
What amount of flexion-extension is accommodated by the atlanto-occipital joint?
about twenty-five degrees
What amount of axial rotation is accommodated by the atlanto-occipital joint?
about three to eight degrees one side axial rotation
What amount of lateral bending is accommodated by the atlanto-occipital joint?
about five degrees
Which motion is best accommodated by the atlanto-occipital joint?
Which atlanto-axial joint is identified as a synovial pivot joint (diarthrosis trochoid)?
the median atlanto-axial joint
Which atlanto-axial joint is identified as a synovial plane (diarthrosis arthrodia)?
the lateral atlanto-axial joint
What are the names given to the synovial joint spaces of the median atlanto-axial joint?
the anterior bursa and the posterior bursa
What part of the vertical crus ligament may be absent?
the inferior crus ligament
What is the function of the transverse atlantal ligament?
it is the primary stabilizer of the atlanto-axial joint restricting the distance of C2 from the anterior arch of C1
What is ADI?
the Atlanto-Dental Interspace, a radiographic distance between the surfaces of the anterior bursa of the median atlanto-axial joint
What is the ADI of children compared with that of adults?
about 4.5 mm in children; a range of 2-3 mm or about 2.5 mm in adults
What are the attachment sites for the accessory atlanto-axial ligament?
the 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
What is the homolog of the posterior atlanto-axial ligament?
the ligamentum flavum
What are the degrees of movement facilitated at the atlanto-axial joint?
about 20 degrees felxion-extension, 40 degrees one side axial rotation, and 5 degrees of lateral bending