B. Atypical Cerival Vertebrae: C1/Atlas Flashcards
What is the name for the first cervical vertebrae?
atlas
What features are lacking at C1?
vertebral body, pedicles, a spinous process and the intervertebral disc
What osseous modification is observed to the front of the anterior arch of C1?
anterior tubercle
What muscle attaches to the anterior arch of C1?
longus colli
What ligaments will attach to the anterior arch of C1?
the anterior-longitudinal, anterior atlanto-occipital and anterior atlanto-axial ligaments
What is observed on the back of the anterior arch of C1?
the fovea dentis
What is the morphology of the superior articular facet of C1?
they are elliptical, closer together in front and often demonstrate an elevation subdividing the facet surface into two separate surfaces
What is the orientation of the superior articular facet of C1?
backward, upward, medial (BUM)
What is the joint classification of the atlanto-occipital zygaophophysis?
synovial (diarthrosis) ellipsoidal joint
What are the morphological characteristics of the inferior articular facet of C1?
asymmetrical, slightly concave or flattened
What is the orientation of the inferior articular facet of C1?
backward, medial, downward (BMD)
What is the name of the rounded elevation on the medial aspect of the lateral mass of C1?
tubercle for the transverse atlantal ligament
What muscles attach to the lateral mass of C1?
levator scapula, splenius cervicis, and rectus capitis anterior
What part of C1 represents the spinous process?
posterior tubercle of the posterior arch
What is the distance from the posterior tubercle of the posterior arch to the skin in each gender?
males: about 50 mm
females: about 37 mm
What attaches to the posterior tubercle of the posterior arch of C1?
rectus capitis posterior minor muscle and ligamentum nuchae
What superior surface modifications of the posterior arch of C1 are present?
groove/sulcus for the vertebral artery and arcuate rim