9. Vertebrae Flashcards
What are the features of a typical cervical vertebrae?
Bifid spinous process
Transverse foramen in transverse process
Large triangular foramen
Small, broad vertebral body
What is carried in the transverse foramen?
vertebral artery and vein (C6 upwards)
C7 carries accessory vertebral vein
What are that articulations of the atlas?
Skull - atlo-occipital joint
Axis - atlanto-axial joint
What movement is the atlanto-axial joint responsible for?
50 % total rotation
What movement is the alto-occipital joint responsible for?
50% flexion and extension (nodding)
What are the features of the atlas?
No vertebral body
No spinous process
Vertebral arches thick and strong
What are the features of the axis?
Odontoid process/ dens
Rugged lateral mass
Large spinous process
What ligament is on the axis?
Transverse ligament
What is the function of the dens and transverse process?
Prevent horizontal displacement of atlas
What vertebrae is referred to as the vertebra prominens?
C7
What are the features of C7?
Largest spinous process
Spinous process NOT bifid
Transverse foramen is small - only carries accessory veins
Ligamentum nuchae is a thickening of which ligament?
Supraspinous ligament
What is the function if the ligamentum nuchae?
Maintains secondary curvature of cervical spine
Helps cervical spine support the head
Major site of attachment of neck and trunk muscles (trapezius, rhomboids)
What are the features of thoracic vertebrae?
Demi-facets on sides of vertebral body
Costal facets on transverse processes
Vertebral foramen circular and small
Heart shaped vertebral body
Which vertebrae have demi-facets? What is their function?
T2-T8 articulate with the head of ribs
Which vertebrae have whole facets?
T9 and T10
What do the costal facets of thoracic vertebrae articulate with?
Tubercle of rib
What is the function of the anterior region of the spinal cord?
Sensory and motor
- light touch, pin prick and pain
What is the function of the posterior region of the spinal cord?
Vibration and proprioception
What region of the spinal cord is responsible for leg and arm innervation?
Legs - lateral
Arms - central
Where do the nerve roots exit from the spinal cord?
Until C7 - Above vertebral body
From C7/T1 - below vertebral body
What is cervical spondylosis?
Degenerative, age-related osteoarthritis in intervertebral facet joints in cervical spine.
What are the complications of cervical spondylosis?
Can develop either/both radiculopathy and myelopathy
What leads to radiculopathy, how does it present?
Pressure on the nerve roots
- dermatomal sensory symptoms - parasthesia and pain
- myotomal motor weakness
What causes myelopathy, how does it present?
Pressure on the spinal cord
- global weakness
- gait dysfunction
- loss of balance
- loss of bladder and bowel control
What are the 2 types of axis fracture?
Hangman’s fracture
Peg fracture
What is the commonest cause of Hangman’s fracture?
Hyper-extension
Where is the axis fractured in a hangman’s fracture?
Pars articularis
What happens to the position of the vertebrae in a hangman’s fracture?
Forward displacement of C1 and the body of C2 on C3.
Spinous process’ remain in line.
What is the commonest cause of a peg fracture?
Blow to the back of the head or hyperextension injury
What X-ray is used to assess a peg fracture?
Open mouth AP X-ray
What is a fracture of the atlas called?
Jefferson fracture
Where is the atlas broken in a jefferson fracture?
Fracture of the anterior and posterior arches of atlas
What is the commonest mechanism of Jefferson fracture?
Axial loading - e.g diving into shallow water
Is a whiplash injury considered high or low energy?
Low energy
What is the mechanism leading to whiplash injury?
Hyperextension followed by hyperflexion
What nerve root will be affected by a C7/T1 prolapsed disc?
C8
What is the commonest cause of thoracic cord compression?
Fractures
Tumours
