Anatomy & Physiology: Bone Quiz Review #4

VERTEBRAL ARCH

A circle of bone around the canal through which the spinal cord passes. A vertebral arch is composed of a floor at the back of the vertebra, walls (the pedicles), and a roof where two laminae join.

DENS PROCESS

A strong toothlike process projecting upward from the body of the axis (second cervical vertebra), or epistropheus, around which the atlas rotates.

ATLAS

The atlas is the topmost vertebra and with the axis forms the joint connecting the skull and spine.

AXIS

The axis is the second of seven bones in the cervical spine. It creates a pivot that allows the atlas to rotate. This action gives the head and neck a greater range of motion from side to side.

LUMBAR VERTEBRAE

The five vertebrae situated between the thoracic vertebrae and the sacral vertebrae in the spinal column.

SACRUM

There are 5 sacral vertebral bones. They are situated between the lumbar vertebrae and the coccyx (the lowest segment of the vertebral column). The sacral vertebrae are normally fused to form the sacrum; a triangular bone in the lower back formed from fused vertebrae and situated between the two hipbones of the pelvis.

VERTEBRAL BODY

Vertebral body is the thick oval segment of bone forming the front of the vertebra also called the centrum. The cavity of the vertebral body consists of cancellous bone tissue and is encircled by a protective layer of compact bone. Bony structures called pedicles protrude from each side of the vertebral body and join with the laminae to form the vertebral arch. The upper and lower surfaces of the vertebral body are flat and rough to provide attachment for the vertebral discs that lie between each vertebra.

INFERIOR ARTICULAR PROCESSES

a bony outgrowth on a vertebra that forms a joint with an adjoining vertebra.

SUPERIOR ARTICULAR PROCESSES

a bony outgrowth on a vertebra that forms a joint with an adjoining vertebra.

SPINOUS PROCESS

a bony projection off the posterior (back) of each vertebra. The spinous process protrudes where the laminae of the vertebral arch join and provides the point of attachment for muscles and ligaments of the spine.

SACRAL CANAL

a continuation of the vertebral canal and runs throughout the greater part of the sacral bone.

INTERVERTEBRAL FORAMINA

a foramen between two spinal vertebrae. Cervical, thoracic, and lumbar vertebrae all have intervertebral foramina. The foramina, or openings, are present between every pair of vertebrae in these areas.

TRANSVERSE FORAMEN

a foramen in each transverse process of a cervical vertebra through which the vertebral artery and vertebral vein pass in each cervical vertebra except the seventh.

ALAE

a large triangular surface on either side of the body of the base of the sacrum. The alae support the psoas major muscles and the lumbosacral trunk which connects the lumbar plexus with the sacral plexus. In the articulated pelvis the alae are continuous with the iliac fossa.

SACRAL HIATUS

a normally occurring gap at the lower end of the sacrum, exposing the vertebral canal, due to failure of the laminae of the last sacral segment to coalesce. It is closed by the sacrococcygeal ligament and provides cannular access to the sacral epidural space for administration of anesthetics (caudal nerve blocks).

LAMINAE

a posterior arch of the vertebral bone lying between the spinous process (which juts out in the middle) and the more lateral pedicles and the transverse processes of each vertebra. The pair of laminae, along with the spinous process, make up the posterior wall of the bony spinal canal.

TRANSVERSE PROCESS

a small bony projection off the right and left side of each vertebrae. The two transverse processes of each vertebrae function as the site of attachment for muscles and ligaments of the spine as well as the point of articulation of the ribs (in the thoracic spine).

COCCYX

a small, triangular bone at the base of the spinal column in humans and some apes, formed of fused vestigial vertebrae.

PEDICLES

a stub of bone that connects the lamina to the vertebral body to form the vertebral arch. Two short, stout processes extend from the sides of the vertebral body and joins with broad flat plates of bone (laminae) to form a hollow archway that protects the spinal cord.

MEDIAL SACRAL CREST

an unpaired crest formed by the fused spinous processes of the upper four sacral vertebrae.

VERTEBRAE

each of the series of small bones forming the backbone, having several projections for articulation and muscle attachment, and a hole through which the spinal cord passes.

THORACIC VERTEBRAE

each of the twelve bones of the backbone to which the ribs are attached.

VERTEBRAL CANAL

the canal formed by the series of vertebral foramina together, enclosing the spinal cord and meninges.

SACRAL PROMONTORY

the most prominent anterior projection of the base of the sacrum.

VERTEBRAL FORAMEN

the opening formed by a neural arch through which the spinal cord passes

CERVICAL VERTEBRAE

the top 7 vertebrae of the spine and form the neck, which supports the skull, or cranium. The atlas is the first cervical vertebra (C1) and it forms the atlanto-occipital joint with the occipital bone, at the base of the skull.