arthro class3 Flashcards
articular form and function
Each articulation has its characteristic relationship between structure and function. When we understand this relationship we begin to understand the relationship between movement and structure. To describe human movement you need
a frame of reference that permits accurate and precise communication.
We can classify the synovial joints according to their anatomical structure and
functional properties. To demonstrate the basis for that classification, we will use
a simple model to
dynamic motion
An articulation that does only gliding movements or that permits movement along
only one axis is usually known as uniaxial or mono-axial.
If movement can occur along two axes , the articulation is usually biaxial.
The most mobile joints permit a combination of angular movement and rotation.
These are said to be multi-axial or triaxia
gliding
In gliding, two opposing surfaces slide past one another, as in possible
movement 1 (activity earlier). Gliding occurs between the surfaces of
articulating carpal bones and between tarsal bones. The movement can occur
in almost any direction, but the amount of movement is slight, and rotation is
generally prevented by the capsule and associated ligaments.
angular motion
Examples of angular motion include flexion, extension, abduction,
adduction, and circumduction. The descriptions of the movements are
based on reference to an individual in the anatomical position.
Flexion and Extension - occur in the sagittal plane
Abduction and Adduction - occur in the coronal/frontal plane
Circumduction - occurs in the oblique plane of reference, depending on the
angle we are referring to
rotational movements
Described with reference to a figure in the anatomical position. Rotation of the
head may involve left rotation or right rotation. Limb rotation may be described
by reference to the longitudinal axis of the trunk. During medial rotation, also
known as internal rotation, the anterior surface of a limb turns toward the
long axis of the trunk. The reverse movement is called lateral rotation, or
external rotation.
The articulations between the radius and ulna permit the rotation of the distal
end of the radius across the anterior surface of the ulna. This rotation moves
the wrist and hand from palm-facing-front to palm-facing-back. This motion is
pronation. The opposing movement, in which the palm is turned anteriorly, is
supination.
inversion
(in, into + vertere, to turn) is a twisting motion of the foot that turns the
sole inward. The opposite movement is called eversion, turning the sole of the
foot outward. (please note we will discuss the combined movements known as
pronation and supination of the foot in future levels at VCMT. These actions refer
to gait and they are more complex than simple inversion and eversion).
dorsiflexion
is flexion of the ankle, as when you dig in your heel. Plantar flexion (planta, sole), the opposite movement, extends the ankle and elevates the
heel, as when you stand on tiptoe.
opposition
is a special movement of the thumb that involves the carpometacarpal and metacarpophalangeal joints. Opposition permits you to grasp
and hold an object with your thumb and palm.
protraction
involves moving a part of the body anteriorly in transverse plane.
You protract your scapula when you hunch forward at your desk with shoulders
rolled forward. Retraction is the reverse movement, drawing the scapulae back
together.
protusion
refers to jutting your MANDIBLE forward at the JAW. Retrusion refers to
tucking your chin and drawing your mandible back.
elevation and depression
occur when a structure moves in a superior or inferior direction, respectively. You depress your mandible when you open your mouth;
Rotational movements
Described with reference to a figure in the anatomical position. Rotation of the
head may involve left rotation or right rotation. Limb rotation may be described
by reference to the longitudinal axis of the trunk. During medial rotation, also
known as internal rotation, the anterior surface of a limb turns toward the
long axis of the trunk. The reverse movement is called lateral rotation, or
external rotation.
The articulations between the radius and ulna permit the rotation of the distal
end of the radius across the anterior surface of the ulna. This rotation moves
the wrist and hand from palm-facing-front to palm-facing-back. This motion is
pronation. The opposing movement, in which the palm is turned anteriorly, is
supination.
Vancouver College of Massage Therapy- Arthrology 100
you elevate it as you close it. Another familiar elevation occurs when you shrug
your shoulders.
lateral flexion
occurs when your vertebral column or head bends to the side.
This movement is most pronounced in the cervical and thoracic regions
synovial joints
Synovial joints permit a wide range of motion. A synovial joint is surrounded by
a fibrous articular capsule and a synovial membrane lines the articular cavity.
These joints are typically found at the ends of long bones, such as those of the
upper and lower limbs.
gliding jonts
also called planar joints, have flattened or slightly curved
faces. The relatively flat articular surfaces slide across one another, but the
amount of movement is very slight. Although rotation is theoretically possible
at such a joint, ligaments usually prevent or restrict such movement. Gliding
joints are found between the carpal bones, between the tarsal bones, and
between the articular facets of adjacent spinal vertebrae
hinge
permit angular movement in a single plane, like the opening
and closing of a door. A hinge joint is a monaxial joint. Examples include the
joints of the elbow, knee, ankle, and interphalangeal joints.
