Transcript The Shoulder Girdle

The Shoulder Girdle
Anatomy and Physiology of
Human Movement
420:050
Objectives
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Bones, bony landmarks and joints
Muscles
Movements
The Shoulder Girdle
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The scapula and clavicle
Two joints
Functions
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Dynamic stability
Increased ROM
From Seeley RR, Stephens TD, Tate P; anatomy and
physiology, ed 7, New York, 2006, McGraw-Hill
From Seeley RR, Stephens TD, Tate P; anatomy and
physiology, ed 7, New York, 2006, McGraw-Hill
Joints
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Shoulder girdle (scapulothoracic)
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Scapula moves on the rib cage
Joint motion occurs at sternoclavicular joint & to a
lesser amount at the acromioclavicular joint
Joints
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Sternoclavicular (SC)
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(Multiaxial) arthrodial/gliding
classification
Movements
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Anteriorly with
protraction
Posteriorly with
retraction
Superiorly with
elevation
Inferiorly with
depression
Joints
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Acromioclavicular (AC)
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Movements
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Arthrodial/gliding
classification
Some gliding & rotational
motion accompanying
other shoulder girdle &
shoulder joint motions
Often injured
Objectives
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Bones, bony landmarks and joints
Muscles
Movements
Muscles
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Five muscles primarily involved in shoulder
girdle movements
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All originate on axial skeleton & insert on scapula
and/or clavicle
Do not attach to humerus & do not cause
shoulder joint actions
Functions:
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Stability
ROM of shoulder joint
Shoulder Girdle Muscles
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Five muscles primarily
involved in shoulder
girdle movements
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Trapezius - upper,
middle, lower
Rhomboid - deep
Levator scapula
Serratus anterior
Pectoralis minor - deep
Trapezius
Levator Scapulae
Rhomboids
Serratus Anterior
Pectoralis Minor
Subclavius
Objectives
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Bones, bony landmarks and joints
Muscles
Movements
Movements
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Focus on specific bony
landmarks
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inferior angle
glenoid fossa
acromion process
Shoulder girdle
movements = scapula
movements
Movements
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Elevation
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upward or superior
movement, as in shrugging
shoulders
Depression
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downward or inferior
movement, as in returning to
normal position
Movements
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Abduction (protraction)
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scapula moves laterally
away from spinal column
Adduction (retraction)
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scapula moves medially
toward spinal column
Movements
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Upward rotation
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turning glenoid fossa upward
& moving inferior angle
superolaterally away from
spinal column
Downward rotation
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returning inferior angle
inferomedially toward spinal
column & glenoid fossa to
normal position
Elevation
Shoulder
Girdle
Movements
Abduction
Adduction
Depression
Movements
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Anterior tilt (upward tilt)
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Rotational movement of scapula about frontal axis
Occurs during glenohumeral hyperextension
Posterior tilt (downward tilt)
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Rotational movement of scapula about frontal axis
Occurs during glenohumeral hyperflexion
Movements
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Lateral tilt (outward tilt)
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Rotational movement about its vertical axis
Occurs during protraction
Medial tilt (return from lateral tilt, inward tilt)
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Rotational movement about its vertical axis
Occurs during retraction
Movements
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Shoulder joint & shoulder girdle work together
Shoulder girdle movement independent
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Upward/downward rotation?
Shoulder girdle muscles
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Stabilize scapula
Enhance ROM of shoulder joint
ELEVATION
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Proximal attachment:
Above or below
scapula/clavicle?
How many muscles fit
this criteria?
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Upper fibers trapezius
Middle fibers trapezius
Rhomboids
Levator Scapulae
DEPRESSION
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Proximal attachment:
Above or below
scapula/clavicle?
How many muscles fit
this criteria?
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Lower fibers trapezius
Pectoralis minor
Subclavius
RETRACTION
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Proximal attachment: In
front (ribs) or behind
(spine)?
How many muscles fit
this criteria?
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Trapezius (all fibers)
Rhomboids
Levator scapulae
PROTRACTION
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Proximal attachment: In
front (ribs) or behind
(spine)?
How many muscles fit
this criteria?
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Serratus anterior
Pectoralis minor
UPWARD ROTATION
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Upward or downward
torque?
How many muscles fit
this criteria?
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Trapezius (all fibers)
Serratus anterior
DOWNWARD ROTATION
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Upward or downward
torque?
How many muscles fit
this criteria?
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Pectoralis minor
Rhomboids