Exam 2- Atypical Cervical Vertebra Flashcards
What features are lacking at C1
Vertebral body, pedicles, a spinous process and the intervertebral disc
What muscle attaches to the anterior arch of C1
Longus Colli
What ligaments will attach to the anterior arch of C1
The ALL, 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
BUM
What is the joint classification of the Atlanto-occipital zygapophysis
Synovial ellipsoidal joint
What are the morphologic characteristics of the inferior articular facet of C1
Asymmetrical, slightly concave or flattened
What is the orientation of the inferior articular facet of C1
BMD
What is the joint classification of the Atlanto-axial zygapophysis
Synovial plane joint
What is the name of the rounded elevation on the medial aspect of the lateral mass of C1
Tubercle of the transverse atlantal ligament
What muscles attach to the lateral mass of C1
Lavator scapula, splenius cervicis and rectus capitis anterior
What is the contribution of the posterior arch to the circumference of C1
40%
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
Male: 50mm
Female: 37mm
What attaches to the posterior tubercle of the posterior arch of C1
Rectus capitis posterior minor muscle and ligamentum nuchae
What attaches to the arcuate rim of C1
The posterior Atlanto-occipital ligament
Ossificaiton of the free margin of the posterior atlanto-occipital ligament results in which atypical bone classification
Accessory bone
What is the earliest age of development where ossification of the anterior free margin of the posterior antlanto-occipital ligament was observed
About the age of 7
What may be formed by ossification of the anterior free margin of the posterior Atlanto-occipital ligament
A partial ponticulus posticus or complete ponticulus posticus
What other name may be used to identify a ponticulus posticus
Kimmerle’s anaomaly
What names are given to the opening formed by the ponticulus posticus
Arcuate foramen or retroarticular canal
Ponticulus posticus has been observed in what ethnic populations
All ethnic populations studied this fare
What is the general range of incidence of ponticulus posticus in the populations studied
1%-41%
What is the gender bias now associated with ponticulus posticus
Female
What is the location of the “zygapophysis” relative to the Atlanto-occipital and Atlanto-axial interverterbal foramen
It forms part of the anterior boundary of the intervertebral foramen in both cases
What are the osseous parts of the transverse process of C1
Costal element, posterior tubercle, true transverse process
What osseous parts of the transverse process are absent at C1
Anterior tubercle and costotransverse bar
What muscles attach to the transverse process of C1
Rectus capitis anterior, rectus capitis lateralis, middle scalene, lavator scapula, splenius cervicis, obliquus capitis inferior and intertransversarri muscles
What suboccipital muscles are known to have fascial projections attaching to the spinal dura
Rectus capitis posterior minor, rectus capitis posterior major, obliquus capitis inferior
What are the connections between suboccipital muscles and the spinal dura called
Myodural bridges
What are the lateral bridges of atlas connected to
The lateral mass and the transverse process of atlas
What opening is identified when a complete lateral bridge is formed
The retrotransverse foramen
Wha are the possible contents of the retrotransverse foramen
The vertebral artery, a branch from the suboccipital nerve and veins communicating with the venous sinuses of the neck
Which of the ponticles of atlas is only observed in humans
Lateral bridges
What is observed in the transverse foramen of C1
Vertebral artery, vertebral venous plexus, postganglionic sympathetic motor nerve fibers
What is the gender variation of measurements of the transverse diameter of C1
Male: 78mm
Females: 72mm
What is the distance from the posterior tubercle of the transverse process of C1 to the skin for each gender
A little over 30mm for both males and females
What joint classifications are observed at C1
Fibrous syndesmosis joint, synovial ellipsoidal joint, synovial pivot joint and synovial plane joint
How many synovial joint surfaces are observed at C1
Five
What is the name of the first cervical vertebra
Atlas
