Download Joint Anatomy and Articulation Refrence

Joint Anatomy and Articulation Refrence
The Ankle Joint
The ankle is formed by the junction of three bones: the talus
bone of the foot and the tibia and fibula bones of the shin.
The ligaments that tie and hold the ankle joint together limit
the joint's voluntary movement to about 60 degrees.
However, if the body's weight and external weights are used,
the range of motion of the ankle can be increased.
Actions of the Ankle Joint
Extension
Moving the toes (foot) away from the
body. Also called plantar flexion.
Flexion
Moving the toes (foot) towards the shin.
Also called dorsi flexion.
The Elbow Joint
The elbow joint is a hinged joint formed by the junction of the
humerus and the radius and ulna bones of the lower arm.
Strong ligaments hold the joint together in addition to the
muscles and tendons. There is also movement between the
radius and ulna bones, which allows for pronation and
supination of the forearm.
Actions of the Elbow Joint
Extension
Moving the forearm away from upper
arm in an arm-straightening action.
Flexion
Moving the forearm toward the upper
arm or vice versa.
The Hip Joint
Each half (side) of the pelvic girdle consists of three bones:
the ilium, which is located at the top and sides of the hip; the
pubis, which is below and in front; and the ischium, which is
below and to the rear.
The pelvic basin is closed on the back side by the sacrum
(the lower end of the spine), which is wedged between the
two ilium (hip) bones and held together by the strongest
ligaments in the body. This is commonly known as the
sacroiliac joint, which is often involved in back pain.
The hip joint is formed by the head of the femur (thigh bone)
articulating in the acetabulum, a deep socket formed on the
outer surface of the pelvis where the ilium, pubis, and
ischium bones join together. The hip joint is a ball-and-socket
joint, which means that the leg can rotate in all directions
inside the socket. Strong ligaments surround and hold the
joint together and limit the amount of movement that is
possible in the joint, usually to 30-45 degrees from the
anatomical position (when the legs and body form a straight
line).
In this arrangement the thigh can move in only a limited
range of motion when the pelvic girdle is held stationary.
When the pelvis also rotates, the leg can be raised through a
greater range of motion. In most movements of the leg there
is a combination of both thigh and pelvic movement. When
the leg is stationary, movement of the pelvis increases the
range of motion of the trunk in all directions. Thus, the pelvis
plays an important role in many movements.
Actions of the Hip Joint
Extension
Moving the leg down and back to the
anatomical straight-line position from a
hip-flexed position.
Flexion
Moving the thigh forward at the hip.
Abduction
Moving one leg from the mid-line of the
body out towards the side of the body.
Adduction
Moving one leg toward the other leg
(toward the mid-line of the body) from an
out-to-the-sides position.
Lateral Rotation Rotation of the femur outward (away
from the other leg).
Medial Rotation
Rotation of the femur inward (toward
the other leg).
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Joint Anatomy and Articulation Refrence
The Knee Joint
The knee is a very unstable and complex joint. It is formed by
the articulation of the femur (thigh bone) with the fibula and
tibia bones of the shin. The knee joint is a hinge joint and its
action is similar to the movement of a door on hinges.
However, it is not a true hinge joint because some rotation
and sliding of the bones is possible when the knee is bent.
The knee joint is stabilized and held together by many
ligaments and tendons. The ligaments also play an important
role in limiting the range of motion in the joint. If they did not
perform this function, the bones of the knee joint would
literally pop apart when you assume the extreme position of
flexion as in a deep squat.
Your knees must not only support your weight, but must also
be used so that you can walk, run, jump, and so on. In
addition, the knee plays a major role in shock absorbing
during jumping and running. Because of this and because
the knee is anatomically unstable, it is very important that
you develop all of the muscles around the knee.
Actions of the Knee Joint
Extension
Moving the shin away from the back of
the thigh or vice versa.
Flexion
Moving the back of the shin towards the
back of the thigh or vice versa.
The Radio-Ulnar Joint
The radio-ulnar joint is the combination of three joints: The
proximal (elbow), middle, and distal (wrist) radio-ulnar joints.
The proximal radio-ulnar joint is a pivot joint between the
head of the radius and the radial notch of the ulna. The
middle radio-ulnar joint is a slightly movable ligamentous
joint. The forearm bones are connected by a ligamentous
sheath, the interosseous membrane. This membrane
prevents undo separation of the two bones, and it acts to
transmit and cushion the longitudinal forces of weight
bearing. For example, when the arm is in a supporting
position, the body weight is transferred from the humerus
primarily to the ulna, and the force of resistance from the
hand is transferred primarily to the radius at the wrist joint.
The distal radio-ulnar joint is a pivot joint between the distal
head of the ulna and the ulna notch of the radius. In
pronation and supination, the end of the radius around the
head of the ulna and rotates on its long axis.
Actions of the Radio-Ulnar Joint
Pronation
Rotating the forearm so that the hand is
turned palm down.
Supination
Rotating the forearm so that the hand is
turned palm up.
The ShoulderJoint
The shoulder is the most freely movable of all the body 's balland-joint socket joints. Because of this, the greatest variety
and combination of movements at a joint can be executed by
the arm from the shoulder joint.
The shoulder joint is formed by the articulation of the glenoid
fossa of the scapula (shoulder blade) and the head of the
humerus (upper arm bone). The shoulder joint consists of a
shallow socket (glenoid cavity) into which the half-spherical
head of the humerus fits. It should be noted that less than
half of humerus is in the socket at any time. Because of this,
the bony arrangement is very weak and therefore the
strength of the musculature around the shoulder is very
important for stability.
It is impossible to talk about the movements of the shoulder
without also discussing the shoulder girdle, which consists of
the scapula and clavicle (collar bone). The clavicle joins the
sternum (breast bone) at the sternoclavicular joint, which
allows for full-range movement of the outer (shoulder) end of
the clavicle. The outer end of the clavicle joins the scapula at
the acromion in what is know as the acromioclavicular joint .
Because the clavicle cannot move by itself, movements of
the shoulder girdle are usually referred to as movements of
the scapula, which is free to move in all directions. Thus,
scapula movements allow for a greatly increased range of
motion in the shoulder joint by changing the position of the
joint.
Actions of the Shoulder Joint
Extension
Moving the arm down and to the rear.
Flexion
Moving the arm upward and in front
of the body.
Abduction
Moving the arm sideward and upward
away from the body.
Adduction
Moving the arm sideward and
downward towards the body.
Horizontal
Moving the arm horizontally from the
Extension
front of the body towards the side. Also
called shoulder joint horizontal
abduction.
Horizontal
Moving the arm horizontally towards
Flexion
the front of the body. Also called
shoulder joint horizontal adduction.
Horizontal
Moving the arm horizontally from the
Abduction
front of the body towards the side.
Horizontal
Moving the arm horizontally towards the
Adduction
front of the body.
Lateral Rotation Rotation of the humerus outward.
Medial Rotation
Rotation of the humerus inward.
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Joint Anatomy and Articulation Refrence
The Spine
The spinal column is a unique and well designed structure. It
has a total of 24 vertebrae, and because each vertebrae
must support the weight of all the body parts above it, the
lower vertebrae are much larger than the upper ones.
Attached to the thoracic (chest) vertebrae are 12 pairs of ribs
which form the skeleton of the thorax (chest cavity).
The Wrist Joint
There are several "wrist joints". First, there is the articulation
in the radio-carpal joint formed by the end of the end of the
radius bone of the forearm and three of the first row of carpal
(wrist) bones (the scaphoid, lunate, and triquetrum). The ulna
bone of the forearm does not participate because it is
separated from the carpals by a disc of fibrocartilage.
Cartilaginous intervertebral discs are located between the
vertebrae. The discs are composed of a jell-like mass
surrounded by a heavy, strong layer of fibrocartilage. The
discs permit motion between the vertebrae and also provide
a cushion for them. The vertebrae are held together by
muscles and ligaments which extend from the skull down to
the sacrum.
The two rows of carpal bones articulate at the intercarpal
joints. The carpal bones glide across one another and allow
some flexion and slight extension. Also, the carpal bones in
each row articulate with the bone or bones adjacent to them
in the same row. Movements of the thumb is atypical
because it includes many varied and different movements.
The spine has four normal curves which can be seen when it
is viewed from the side. The cervical (neck) and lumbar
(lower back) curves are concave to the rear, and the thoracic
(chest) and sacral (pelvic) curves are convex to the rear.
There is a smooth transition from one curve into another.
This arrangement gives effective support to the spine and
allows for independent movement of different sections of the
spine.
Movements of the spine take place by compression and
deformation of the elastic intervertebral discs and by the
gliding of the articular processes of the vertebrae
(protrusions at the top and bottom of each vertebrae) upon
one another. The range of movement of each individual
spinal (vertebral) joint is very small. However, when many
vertebrae are involved at one time, the total movement of all
the joints can appear to be very large. The limited range of
interspinal motion is due to the tight ligaments and the shape
and positioning of the interlocking parts of the vertebrae. In
the thoracic area the ribs limit the range of motion.
Actions of the Spine
Extension
Return from a position of flexion to the
anatomical position of the spine.
Flexion
Forward bending of the spine.
Lateral Flexion
Bending sideways to the right or left.
Rotation
Rotation of the shoulders around the
spine.
Actions of the Wrist Joint
Extension
Moving the back side of the hand
towards the posterior surface of the
forearm.
Flexion
Moving the palm side of the hand
towards the forearm.
Abduction
Moving the thumb side of the hand away
from the body when the arm is in the
anatomical position, that is, when the
palm faces forward. Also called radial
flexion.
Adduction
Moving the little finger side of the hand
towards the body when the arm is in the
anatomical position, that is, when the
palm faces forward. Also called ulna
flexion.
Radial Flexion
Moving the thumb side of the hand away
from the body when the arm is in the
anatomical position, that is, when the
palm faces forward.
Ulna Flexion
Moving the little finger side of the hand
towards the body when the arm is in the
anatomical position, that is, when the
palm faces forward.
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Kinesiology of Exercise ebooks based on the work of Dr. Michael Yessis
Volume 1 - The Ankle Joint
Volume 2 - The Knee Joint
Volume 3 - The Hip Joint and Pelvic Girdle
Volume 4 - Combination Exercises
Volume 5 - The Spine: The Abdominals
Volume 6 - The Spine: Lower Back Muscles
Volume 7 - The Shoulder Joint
Volume 8 - The Elbow Joint
Volume 9 - The Radio-Ulnar Joint
Volume 10 - The Wrist Joint
Volume 11 - Combined Shoulder and Arm Exercises
Bonus 1 – Introduction to Biomechanics
Bonus 2 – Training Factors
Bonus 3 – Training Recommendations
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Copyright © 2016 KinX Learning Inc. All Rights Reserved