Editing Cervical vertebrae (section)

===Vertebra prominens===
[[File:C7 animation small.gif|thumb|right|200px|Position of C7 shown in red.]]
The '''vertebra prominens''', or C7, has a distinctive long and prominent spinous process, which is palpable from the skin surface. Sometimes, the seventh cervical vertebra is associated with an abnormal extra rib, known as a [[cervical rib]], which develops from the anterior root of the transverse process. These ribs are usually small, but may occasionally compress blood vessels (such as the [[subclavian artery]] or [[subclavian vein]]) or nerves in the [[brachial plexus]], causing pain, numbness, tingling, and weakness in the upper limb, a condition known as [[thoracic outlet syndrome]]. Very rarely, this rib occurs in a pair.

The long spinous process of C7 is thick and nearly horizontal in direction. It is not bifurcated, and ends in a tubercle that the [[ligamentum nuchae]] attaches to. This process is not always the most prominent of the spinous processes, being found only about 70% of the time, C6 or [[Thoracic vertebrae|T1]] can sometimes be the most prominent.

The transverse processes are of considerable size; their posterior roots are large and prominent, while the anterior are small and faintly marked. The upper surface of each usually has a shallow sulcus for the eighth spinal nerve, and its extremity seldom presents more than a trace of bifurcation.

The transverse foramen may be as large as that in the other cervical vertebrae, but it is generally smaller on one or both sides; occasionally, it is double, and sometimes it is absent.

On the left side, it occasionally gives passage to the vertebral artery; more frequently, the vertebral vein traverses it on both sides, but the usual arrangement is for both artery and vein to pass in front of the transverse process, not through the foramen.