Question

Neural spine of the atlas vertebra of man is directed in the
(A) Upward and backward direction
(B) Upward and forward direction
(C) Downward and backward direction
(D) Absent

Answer 1

Hint: Cervical spine is made up of a total of seven vertebrae. The first cervical vertebra of man lacks in the neural spine. The first cervical supports the skull on top of the vertebral column.

Complete step by step answer:
The first cervical (C1) vertebra is also called the atlas and it lacks in the Neural spine. The first two i.e, C1 and C2, are highly specialized and are given specific names which are atlas and axis, respectively. The name Atlas was related to the Greek God Atlas because, just as Atlas supported the globe, it supports the entire head.

So, the correct answer is ‘Absent’.

Additional Information: The atlas is situated at the top and, along with the axis, it forms the joint which is connecting the skull and spine. The atlas and axis are specialized to permit a greater range of motion than normal vertebrae. They're liable for the nodding and rotation movements of the top. The atlanto-occipital joint allows the top to nod up and down on the spinal column. The second cervical vertebrae act as a pivot that permits the atlas and attached head to rotate on the axis, side to side. The atlas's chief peculiarity is that it has no body. It's ring-like and consists of an anterior and a posterior arch and two lateral masses. The axis is very important neurologically because the brainstem extends right down to the axis.

Note: A break in the first vertebra is known as a Jefferson fracture. A Jefferson fracture is a bone fracture of the anterior and posterior arches of the atlas vertebra. The name Jefferson fracture was coined after the British neurologist and neurosurgeon Sir Geoffrey Jefferson, who reported four cases of the fracture in 1920.