MRCS Part B (OSCE) - Online Resources

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The typical cervical vertebrae (C3 – C6) are characterised by the following features:

• Broad body
• Small and bifid spine
• Transverse process has a foramen transversarium which transmits the vertebral artery, vertebral vein and sympathetic nerves
• Plane of facet joint is oblique

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C1 vertebra (Atlas) contains occipital condyles for articulating with the skull. It is kidney-shaped and lacks a spinous process or a body.

"C2 vertebra (Axis) contains a peg like dens (odontoid process). It does not have a bifid spine. "

"C7 is also known as the vertebra prominens. The spinous process is long and not bifid. The transverse process is large but the foramina are small and does not transmit the vertebral arteries. The transverse foramina of C7 transmits the vertebral vein. "

"The atlanto-occcipital joint, formed by the articular surfaces of the C1 vertebrae and the occipital condyles. "

"The atlanto-occcipital joint is a synovial joint. It is surrounded by a loose capsule. "

"The alar ligaments (which connect the dens to the occipital condyles) prevent excess rotation at the atlanto-axial joint. "

"The dens (also known as the odontoid process) is the portion of the C2 vertebra about which the C1 and the skull rotate as a unit. "

"The dens can impact the spinal cord, injuring or even severing it resulting in quadriplegia. The dens extends superiorly into the ring of C1 and is therefore susceptible to shearing forces and fracture from C1 in neck injuries. "

"A Hangman’s fracture involves fracture of both pars interarticularis of C2, and results from hyperextension and distraction type injuries. "