Vertebral Column and Hyoid Bone

Flashcards covering key anatomical terms related to the Hyoid Bone and the Vertebral Column, including its structure, components, ligaments, and regional characteristics of vertebrae like the Atlas and Axis.

Hyoid Bone

A floating bone in the neck (anterior view is detailed in notes), associated with muscles like Genioglossus, Geniohyoideus, Mylohyoideus, Omohyoideus, and Thyreohyoidkus.

Vertebral Column

Extends from the skull to the pelvis, forms the body's major axial support, surrounds and protects the spinal cord, and consists of 26 irregular bones.

Cervical Vertebrae (C1-C7)

Seven bones in the vertebral column, located in the neck region. (Mnemonic: Breakfast at 7 am).

Thoracic Vertebrae (T1-T12)

Twelve bones in the vertebral column, located in the chest region. (Mnemonic: Lunch at 12 pm).

Lumbar Vertebrae (L1-L5)

Five bones in the vertebral column, located in the lower back region. (Mnemonic: Dinner at 5 pm).

Sacral Vertebra (Sacrum)

One bone in the vertebral column, formed from 5 fused bones (S1-S5).

Coccygeal Vertebra (Coccyx)

One bone in the vertebral column, formed from 4 fused bones (sometimes 3 or 5).

Intervertebral Discs

Pads of fibrocartilage that separate vertebrae, cushioning them and absorbing shock, composed of a nucleus pulposus and annulus fibrosus.

Nucleus Pulposus

The inner, gelatinous sphere of an intervertebral disc, acting like a rubber ball to absorb compressive stress.

Annulus Fibrosus

The outer collar of an intervertebral disc, made of concentric rings of ligament and fibrocartilage; contains the nucleus pulposus, limits its expansion, and binds vertebrae together.

Anterior Longitudinal Ligament

A ligament that connects bone to bone and prevents hyperextension of the vertebral column.

Posterior Longitudinal Ligament

A ligament that connects bone to bone and prevents hyperflexion of the vertebral column.

Ligamentum Flavum

An elastic connective tissue ligament that stretches and recoils during flexion and extension of the body.

Vertebral Body (Centrum)

The anteriorly located, rounded central portion of a typical vertebra.

Vertebral Arch

A composite structure of a vertebra formed by two pedicles and two laminae.

Pedicles

Short bony walls that project posteriorly from the vertebral body, forming the sides of the vertebral arch.

Laminae

Flat roof plates that complete the vertebral arch posteriorly.

Vertebral Foramen

The central opening formed by the vertebral body and arches, through which the spinal cord is transmitted (successive foramina form the vertebral canal).

Spinous Process

A median, posterior projection from the vertebral arch.

Transverse Process

Projections extending laterally from each pedicle-lamina junction of a vertebra.

Superior Articular Processes

Form movable joints with the inferior articular processes of the vertebra located immediately superior to it, typically facing toward the spinous process.

Inferior Articular Processes

Form movable joints with the superior articular processes of the vertebra located immediately inferior to it, typically facing away from the spinous process.

Intervertebral Foramina

Lateral openings between adjacent vertebrae, formed by notches on the superior and inferior borders of pedicles.

Atlas (C1 Vertebra)

The first cervical vertebra (C1), which has no body or spinous process, and whose superior articular facets receive the occipital condyles of the skull, allowing nodding 'yes'.

Axis (C2 Vertebra)

The second cervical vertebra (C2), which contains a body, a spinous process, and a dens that projects superiorly, acting as a pivot for the rotation of the atlas and skull, allowing the head to shake 'no'.

Dens (Odontoid Process)

A process that projects superiorly from the body of the Axis (C2), fusing with the atlas during embryonic development and serving as a pivot point for head rotation.