Joints And Ligaments Of The Back And Spinal Cord

Front 1

Anterior Longitudinal Ligament Location

Back 1

covers and connects the anterolateral aspects of the vertebral bodies and IV discs
extends longitudinally from the pelvic surface of the sacrum to the anterior tubercle of vertebra C1 and the occipital bone anterior to the foramen magnum

Front 2

Anterior Longitudinal Ligament Actions

Back 2

prevents hyperextension of the vertebral column, maintaining stability of the joints between the vertebral bodies.

the only ligament that limits extension; all other IV ligaments limit forms of flexion.

Front 3

Posterior Longitudinal Ligament Location

Back 3

runs within the vertebral canal along the posterior aspect of the vertebral bodies.

attached mainly to the IV discs and less so to the posterior aspects of the vertebral bodies from C2 to the sacrum, often bridging fat and vessels between the ligament and the bony surface.

Front 4

Posterior Longitudinal Ligament Actions

Back 4

weakly resists hyperflexion of the vertebral column and helps prevent or redirect posterior herniation of the nucleus pulposus.

Front 5

Zygapophysial Joint Articulations

Back 5

plane synovial joints between the superior and inferior articular processes (G. zygapophyses) of adjacent vertebrae

Front 6

Zygapophysial Joint Type

Back 6

plane synovial joints

surrounded by a thin joint capsule that is attached to the margins of the articular surfaces of the articular processes of adjacent vertebrae.

facet joints

Front 7

Zygapophysial Joint Innervation

Back 7

innervated by articular branches that arise from the medial branches of the posterior rami of spinal nerves

As these nerves pass posteroinferiorly, they lie in grooves on the posterior surfaces of the medial parts of the transverse processes

Each articular branch supplies two adjacent joints; therefore, each joint is supplied by two nerves.

Front 8

Uncovertebral Joint Locations

Back 8

at the lateral and posterolateral margins of the IV discs.

between the unci of the bodies of the lower vertebrae and the beveled surfaces of the vertebral bodies superior to them

Front 9

Uncovertebral Joint Type

Back 9

considered synovial joints by some; others consider them to be degenerative spaces (clefts) in the discs occupied by extracellular fluid

articulating surfaces of these joint-like structures are covered with cartilage moistened by fluid contained within an interposed potential space, or “capsule.”

Front 10

Atlanto-occipital Joint Articulations

Back 10

between the superior articular surfaces of the lateral masses of the atlas and the occipital condyles of the cranium

Front 11

Atlanto-occipital Joint Movement

Back 11

permit nodding of the head, such as the flexion and extension of the head occurring when indicating approval (the “yes” movement).

also permit sideways tilting of the head

The main movement is flexion, with a little lateral flexion and rotation

Front 12

Atlanto-occipital Joint Type

Back 12

synovial joints of the condyloid type and have thin, loose joint capsules.

Front 13

Atlanto-axial Joint Articulations

Back 13

three atlanto-axial articulations:
two (right and left) lateral atlanto-axial joints (between the inferior facets of the lateral masses of C1 and the superior facets of C2)

one median atlanto-axial joint (between the dens of C2 and the anterior arch of the atlas).

Front 14

Lateral Atlanto-Axial Joint Type

Back 14

gliding-type synovial joints

Front 15

Median Atlanto-Axial Joint Type

Back 15

pivot joint.

Front 16

Atlanto-axial Joint Movement

Back 16

rotation of the head side-to-side ("No" movement)

During this movement, the cranium and C1 rotate on C2 as a unit.

Front 17

Describe Ligamenta Flava

Back 17

broad, pale yellow bands of elastic tissue that join the laminae of adjacent vertebral arches

long, thin, and broad in the cervical region, thicker in the thoracic region, and thickest in the lumbar region

extend almost vertically from the lamina above to the lamina below, those of opposite sides meeting and blending in the midline

Front 18

Ligamenta Flava Function

Back 18

bind the lamina of the adjoining vertebrae together, forming alternating sections of the posterior wall of the vertebral canal

resist separation of the vertebral lamina by limiting abrupt flexion of the vertebral column, and thereby prevent injury to the IV discs.

help preserve the normal curvatures of the vertebral column and assist with straightening of the column after flexing.

Front 19

Describe the Nuchal Ligament

Back 19

strong, broad, composed of thickened fibroelastic tissue

extends as a median band from the external occipital protuberance and posterior border of the foramen magnum to the spinous processes of the cervical vertebrae

Front 20

Nuchal Ligament Function

Back 20

Because of the shortness and depth of the C3-C5 spinous processes, the nuchal ligament provides attachment for muscles that attach to the spinous processes of vertebrae at other levels.

Front 21

Describe Supraspinous Ligaments

Back 21

strong, fibrous, cord-like

connect the tips of the spinous processes from C7 to the sacrum, merge superiorly with the nuchal ligament at the back of the neck

Front 22

Describe Interspinous Ligaments

Back 22

thin, weak, often membranous

connect adjoining spinous processes, attaching from the root to the apex of each process.

Front 23

Supraspinous and Interspinous Ligament Function

Back 23

unite adjoining spinous processes

Front 24

Describe Intertransverse Ligaments

Back 24

connect adjacent transverse vertebral processes

consist of scattered fibers in the cervical region and fibrous cords in the thoracic region

In the lumbar region these ligaments are thin and membranous.

Front 25

Name the elements of the Intervertebral Disc

Back 25

Each IV disc consists of an anulus fibrosus, an outer fibrous part, composed of concentric lamellae of fibrocartilage, and a gelatinous central mass, called the nucleus pulposus.

Front 26

IV Disc Function

Back 26

provide strong attachments between the vertebral bodies, uniting them into a continuous semirigid column and forming the inferior half of the anterior border of the IV foramen

In aggregate, account for 20-25% of the length (height) of the vertebral column

permit movement between adjacent vertebrae

their resilient deformability allows them to serve as shock absorbers

Front 27

Describe the Nucleus Pulposus

Back 27

the core of the IV disc

not centered in the disc but is positioned between the center and posterior aspect of the disc

avascular; it receives its nourishment by diffusion from blood vessels at the periphery of the anulus fibrosus and vertebral body.

Front 28

Nucleus Pulposus Function

Back 28

semifluid, responsible for much of the flexibility and resilience of the IV disc and of the vertebral column

become broader when compressed and thinner when tensed or stretched (as when hanging or suspended)

during anterior and lateral flexion and extension of the vertebral column, as well as during rotation, the turgid nucleus acts as a semifluid fulcrum

Front 29

Describe the Anulus Fibrosus

Back 29

a bulging fibrous ring consisting of concentric lamellae of fibrocartilage forming the circumference of the IV disc

thinner posteriorly and may be incomplete posteriorly in the adult in the cervical region

becomes decreasingly vascularized centrally, and only the outer third of the anulus receives sensory innervation

Front 30

Microvilli

Back 30

(1) Fingerlike projections containing actin filaments (aka microfilaments) usually covered by glycocalyx.
(2) Appearance can vary widely (number and shape of microvilli correlate with absorptive capacity).
(3)Branched:
a. bleb-like = less active
b. tall = active