Atlanto-Axial Joint Flashcards
Which atlanto-axial joint is identified as a synovial pivot (diarthorsis trochoid)?
the median atlanto-axial joint
Which atlanto-axial joint is identified as a synovial plane (diarthrosis arthorodia)
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 the 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 4.5mm in children; a range of 2-3 mm or about 2.5mm 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 degress of movement facilitated at the atlanto-axial joint?
about 20 degrees flexion - extension, 40 degrees one side axial rotation, and 5 degrees of lateral bending
The occiput-C1-C2 joint complex accounts for what percent of all cervical axial rotation?
about 60%
