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In humans, cervical vertebrae are the smallest of the true vertebrae and can be readily distinguished from those of the thoracic or lumbar regions by the presence of a foramen (hole) in each transverse process, through which the vertebral artery, vertebral veins, and inferior cervical ganglion pass. The remainder of this article focuses upon ...
A fully grown adult features 26 bones in the spine, whereas a child can have 33. Cervical vertebrae (7 bones) Thoracic vertebrae (12 bones) Lumbar vertebrae (5 bones) Sacrum (5 bones at birth, fused into one after adolescence) Coccyx (set of 4 bones at birth)
The number of vertebrae in a region can vary but overall the number remains the same. In a human spinal column, there are normally 33 vertebrae. [3] The upper 24 pre-sacral vertebrae are articulating and separated from each other by intervertebral discs, and the lower nine are fused in adults, five in the sacrum and four in the coccyx, or tailbone.
Each vertebra (pl.: vertebrae) is an irregular bone with a complex structure composed of bone and some hyaline cartilage, that make up the vertebral column or spine, of vertebrates. The proportions of the vertebrae differ according to their spinal segment and the particular species.
Vertebral compartment contains the cervical vertebrae with cartilaginous discs between each vertebral body. The alignment of the vertebrae defines the shape of the human neck. [5] As the vertebrae bound the spinal canal, the cervical portion of the spinal cord is also found within the neck.
The spinal nerves arise from the spinal column. The top section of the spine is the cervical section, which contains nerves that innervate muscles of the head, neck and thoracic cavity, as well as transmit sensory information to the CNS. The cervical spine section contains seven vertebrae, C-1 through C-7, and eight nerve pairs, C-1 through C-8.
In anatomy, the axis (from Latin axis, "axle") is the second cervical vertebra (C2) of the spine, immediately inferior to the atlas, upon which the head rests. The spinal cord passes through the axis. The defining feature of the axis is its strong bony protrusion known as the dens, which rises from the superior aspect of the bone.
The atlas is the topmost vertebra and the axis (the vertebra below it) forms the joint connecting the skull and spine. The atlas and axis are specialized to allow a greater range of motion than normal vertebrae. They are responsible for the nodding and rotation movements of the head.