Transcript File
IMG353
Lecture 1
Introduction to Radiographic Positioning
(Positioning Terminology )
Learning Objectives
By the end of this Lecture the student will be able to:
Define the imaginary planes and body sections
Describe standard positioning terms.
List and identify the meaning of specific terms related to movement
Distinguish Between radiographic projection, position and view
List the four types of body habitus
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References
• Positioning in Radiography: By k.C.Clarke.
• Text book of radiographic positioning and related anatomy; by Kenneth L.Bontrager,
5th edition
Websites
• http://www.e-radiography.net/
• http://www.theodora.com/anatomy/surface_anatomy_index.html
• http://training.seer.cancer.gov/module_anatomy/unit1_3_terminology.html
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Positioning Terminology
Anatomic Position
A person in the anatomical position is
standing erect with the head,
eyes and toes pointing forward,
feet together with arms by the side.
The palms of the hands are also point forward.
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Positioning Terminology
Body Planes
A plane is a flat surface passed through the body
or a portion of the body
Body planes are divided into: Longitudinal planes
◦ Coronal
◦ Sagittal
Horizontal plane
◦ Transverse
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Body Planes
Sagittal Plane (Lateral Plane)
A vertical plane running from front to back;
divides the body or any of its parts into right and
left sides.
Median plane
Sagittal plane through the midline of the body;
divides the body or any of its parts into right and
left halves.
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Body Planes
Coronal or (Frontal)
A vertical plane running from side to side;
divides the body or any of its parts into
anterior and posterior portions.
Axial Plane (Transverse Plane)
A horizontal plane; divides the body or any
of its parts into upper and lower parts.
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Directional Terms
Lateral Vs. Medial
Lateral
Away from the midline of the body
(On the outer side of) e.g. the arms
are lateral to the chest.
Lateral
Medial
Lateral
Medial
Near to the midline of the body
(On the Inner side of) e.g. the
chest is medial to the arms
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Directional Terms
Superior Vs. Inferior
Superior ( cephalic/ cranial)
Towards the head end or towards the
upper part of a structure( above)
e.g. The head is superior to the chest.
Inferior (Caudal)
Away from the head end or towards the
lower part of a structure( Below) e.g.
the abdomen is inferior to the chest.
Superior
Inferior
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Directional Terms
Anterior Vs. Posterior
Anterior ( ventral )
Towards or at front of the body ( in front of)
e.g. The sternum is anterior to the spine.
Posterior (Dorsal )
Towards or at the back of the body ( Behind)
e.g. The heart is posterior to the sternum.
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Directional Terms
Proximal Vs. Distal
Proximal
Close to the origin of the body part or the
point of attachment of a limb to the trunk
e.g. The knee is proximal to the ankle.
Distal
Farther or away from the origin of the body
part or the attachment of a limb to the trunk
e.g. The forearm is distal to the arm.
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Directional Terms
Superficial Vs. Deep
Superficial
Towards or at the body surface
e.g. The skin is superficial to the skeletal muscles
Deep
Away from the body surface ( more internal)
e.g. The skeletal muscles are deep to the skin
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Directional Terms
anterior
posterior
lateral
inferior
caudal
posterior
cephalic
superior
cranial
lateral
proximal
medial
distal
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Joints movement Terms
Abduction vs. Adduction
Abduction :
movement away from the midline of
the body or body part.
Adduction:
Movement toward the midline of the
body or body part.
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Joints movement Terms
Flexion vs. Extension
Flexion :
Decrease in the angle of a joint by bending
Extension:
Increase in the angle of joint or
straightening of a joint
Note : Hyper flexion is over flexion while hyper extension is extension beyond normal limits
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Joints movement Terms
Inversion vs. Eversion
Inversion :
Turning of foot inward at the ankle joint.
Eversion:
Turning of the foot outward at the ankle
joint.
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Joints movement Terms
Pronation vs. Supination
Pronation :
Turning the hand so that the palm is
down or onto one's stomach
Supination:
Turning the hand so the palm is facing
upward or turning onto one's back.
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Body Position Terms
Describe the overall placement of the body in the desired
position.
Erect
"upright"
Position when the Sagittal and coronal planes of the
body are perpendicular to the horizon
Recumbent "lying down"
Position when the transverse plane of the body
is perpendicular to the horizon
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Body Position Terms
Recumbent Positions
Supine
(posterior recumbent position)
◦ Lying down on the back
Prone
(anterior recumbent position)
◦ Lying face down
xx lateral recumbent
◦ lying down on the xx side
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Body Position Terms
Decubitus vs. Recumbent
◦ general meanings are the same "LYING DOWN"
◦ but in radiography, decubitus has a special meaning
◦ DECUBITUS
patient is lying down & the x-ray beam is parallel to the horizon
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Body Position Terms
Decubitus Positions
Ventral decubitus
patient is prone ,Cassette (IR) is vertical &
a horizontal beam is used
Dorsal decubitus
patient is supine ,Cassette (IR) is vertical &
a horizontal beam is used
Lateral decubitus ( Right or Left)
patient lying on the left lateral side ,Cassette
(IR) is vertical & a horizontal beam is used
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Body Position Terms
Oblique (Erect or Recumbent)
Position when the body is rotated so that
the MS plane is neither^ nor to the film
but at an angle
Exact position is indicated by the surface
closest to the film and the angle of rotation
May be erect or recumbent
abbreviations:
◦ RPO, LPO, RAO, LAO
45 RPO
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Body Position Terms
Erect Positions
Surface of body closest to the film used to give
a more specific description
Examples:
Posterior erect -- patient is standing with
the posterior surface of the body next to the
cassette
Left lateral erect -- patient is standing with
the left side of the body next to the cassette
Unit III
Left lateral
erect position
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Body Position Terms
Fowler's Position
A person in the Fowler's position is
sitting leaning slightly back 45o 90o.legs may either be straight or bent.
Trendelenburg Position
A person in the Trendelenburg position
is lying supine with head slightly lower
than their feet.
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Unit III
Body Position Terms
Sim's Position
A near lateral Left anterior oblique ( Left Sim's ) OR right anterior oblique with the top
leg in front the lower leg.
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Positioning Terms
Projection
Refers to the path the x-ray beam takes
through part
Anteroposterior projection
(AP)
Beam enters the front surface and
exits the back surface of the part
Posteroanterior projection (PA)
Beam enters the back and exits the
front of the part
AP projection in supine position
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Positioning Terms
• Lateral Projections
◦ Torso (Trunk) and head
Right to left lateral projection
Left to right lateral projection
◦ Extremities (Limbs)
Mediolateral projection
Lateromedial projection
Note:
Normally the positioning terminology is
used rather than projection.
X-ray
Left lateral erect position
R to L lateral projection
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Positioning Terms
• Special Projections
X-ray beam
Axial Projection
Right to left lateral projection
Left to right lateral projection
Tangential projection
Mediolateral projection
Lateromedial projection
Note:
Normally the positioning terminology is
used rather than projection.
AP axial with 40° caudal angle
X-ray beam
X-ray beam
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Classification of Body Habitus
Hypersthenic
Deep broad thorax
Short thoracic cavity
Short wide heart
Elevated diaphragm
Stomach and GB very high
Colon high and wide
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Unit III
Classification of Body Habitus
Sthenic
Lightly longer and shallow thorax
Ribs more vertical
Heart narrow and longer
Thoracic cavity longer
Diaphragm is not as high
Colon slightly lower and more
centrally located.
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Unit III
Classification of Body Habitus
Hyposthenic
Thorax longer
Diaphragm lower
Stomach and GB lower and
close to midline.
Colon lower and close to
midline of abdomen
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Unit III
Classification of Body Habitus
Asthenic
Exaggeration of Hyposthenic type
Thorax narrow and shallow
Heart longer and narrow
Thoracic cavity longer
Diaphragm is very low
Stomach and GB very lower ,vertical and near midline.
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Unit III
Classification of Body Habitus
Hypersthenic 5%
Unit III
Sthenic 50%
Hyposthenic 35%
Sthenic 10%
Unit III
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