Atypical Cervical Vertebrae C1/Atlas Flashcards
What is the name of the first cervical vertbrae
Atlas
What features are lacking at C1
Vertebral body
pedicles
spinous process
intervertebral disc
What muscles attach to the anterior arch of C1
Longus coli
What ligaments will attach to the anterior arch of C1
Anterior longitudinal ligament
Anterior atalnto-occipital ligament
Anterior atlanto-axial ligament
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 togerther in front
Demonstrate elevation subdividing the facet surfaces into two separate surfaces
What is the orientation of the superior articular facets of C1
Backward, upward, medial (BUM)
What are the morphological caharateristics 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 muscles attach to the lateral mass of C1
Levator scapula
Splenius cervicis
rectus capitis anterior
What is thought to represent the pedicle at C1
The anterior arch
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 is the distance from the posterior tubercle of the posterior arch to the skin in each gender
Males: 50mm
Females: 37mm
What attaches to the posterior tubercle of the posterior arch of C1
rectus capitis posterior minor muscles and ligamentum nuchae
What attaches to the arcuate rim of C1
The posterior atlanto-occipital ligament
Ossification 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 atlanto-occipital ligament was observed
about 7 years of age
What may be formed by ossification of the anterior free margin on 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 anomaly
What names are given to the opening formed by the ponticulus posticus
Arcuate foramen or retroarticular canal
Ponticulus posticus has observed in what ehtnic population
All ethnic populations studies so far
What is the general range of incidence of ponticulus posticus in the populations studied
1%-41%
What is the gender bias now associated with potinculus posticus
female
What is the location of the zygapophysis relative to the atlanto-occipital and atlanto-axial intervertebral foramina
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, ractus captitis lateralis Middle scalene levator scapula splenius cervicis obliquus capitis superior obliquus capitis inferior Intertransversarii muscles
What suboccipital muscles are known to have fascial projections attaching to the spinal dura
Rectus capitis posterir minor
rectus capitis posterior major
obliquud 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
What 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
Males: 78mm
Females: 72mm
What is the distance from the posterior tubercle of the transverse process of C1 to the skin for each gender
little over 30mm for both males and females
What joint classification are observed at C1
Fibrous Syndesmosis joint
Synovial ellipsoidal joint
Synovial pivot joint
Synovial plane joint
How many synovial joint surfaces are observed at C1
five
What synovial joint surfaces are observed at C1
two superior articular facets
two inferior articular facets
fovea dentis
