The Shoulder Joint
Anatomy and Physiology of
Human Movement
420:050
The Shoulder Joint
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Glenohumeral joint
Very mobile but unstable
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Glenoid fossa
Some ligaments
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Lax until extreme ROM
Labrum and rotator cuff
Relationship with shoulder girdle
Objectives
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Bones, bony landmarks and joints
Muscles
Movements
The Shoulder Joint
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Multiaxial ball and socket joint
Able to rotate freely in all three planes
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Sagittal
Frontal
Transverse
Objectives
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Bones, bony landmarks and joint
Muscles
Movements
Deltoid
Pectoralis Major
Coracobrachialis
Latissimus Dorsi
Teres Major
Rotator Cuff
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Supraspinatus
Infraspinatus
Teres Minor
Subscapularis
Rotator Cuff
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Small muscles
Critical for shoulder health
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Dynamic stabilization
Especially important during
overhead repetitious activities
Supraspinatus
Infraspinatus
Teres Minor
Subscapularis
Objectives
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Bones, bony landmarks and joint
Muscles
Movements
Movements
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Flexion
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Movement of
humerus
straight
anteriorly
Extension
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Movement of
humerus
straight
posteriorly
Movements
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Abduction
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Upward lateral movement
of humerus out to the
side, away from body
Adduction
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Downward movement of
humerus medially toward
body from abduction
Movements
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Horizontal adduction
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Movement of humerus in a
horizontal or transverse plane
toward & across chest
Horizontal abduction
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Movement of humerus in a
horizontal or transverse plane
away from chest
Movements
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External rotation
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Movement of humerus
laterally around its long
axis away from midline
Internal rotation
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Movement of humerus
medially around its long
axis toward midline
Movements
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Diagonal abduction
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Movement of humerus in a
diagonal plane away from
midline of body
Diagonal adduction
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Movement of humerus in a
diagonal plane toward
midline of body
LINE OF PULL
FLEXION
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Superior movement of the humerus in the
sagittal plane
Coracobrachialis
FLEXION
FLEXION
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Anterior deltoid
Pectoralis major (upper fibers)
Coracobrachialis
EXTENSION
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Inferior movement of the humerus in the
sagittal plane
Coracobrachialis
EXTENSION
EXTENSION
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Exception  Pectoralis Major Lower Fibers
Effective extensor from hyperflexed position
EXTENSION
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Latissimus dorsi
Teres major
Deltoid (posterior)
Pectoralis major (lower fibers)
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From hyperflexed position
ABDUCTION
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Superolateral movement of the humerus in the
frontal plane
?
ABDUCTION
The location of the line of pull in
relation to the joint center determines
the movement in this case
Hamilton, N. & Luttgens, K. (2007). Kinesiology: Scientific basis of human
motion (11th ed.). McGraw-Hill: New York.
ABDUCTION
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Deltoid (all three)
Pectoralis major (upper fibers)
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Abducted > 90 degrees
ADDUCTION
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Inferomedial movement of the humerus in the
frontal plane
ADDUCTION
The location of the line of pull in
relation to the joint center determines
the movement in this case
Hamilton, N. & Luttgens, K. (2007). Kinesiology: Scientific basis of human
motion (11th ed.). McGraw-Hill: New York.
ADDUCTION
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Latissimus dorsi
Teres major
Pectoralis major (lower fibers)
Pectoralis major (upper fibers)
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Abducted < 90 degrees
HORIZONTAL ABDUCTION
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Movement of the humerus away from the
midline of the body in the transverse plane
HORIZONTAL ABDUCTION
HORIZONTAL ABDUCTION
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Deltoid (posterior)
Latissimus dorsi
Teres major
Infraspinatus
Teres minor
HORIZONTAL ADDUCTION
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Movement of the humerus towards the midline
in the transverse plane
Coracobrachialis
HORIZONTAL ADDUCTION
HORIZONTAL ADDUCTION
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Pectoralis major (upper and lower)
Deltoid (anterior)
Coracobrachialis
INTERNAL ROTATION
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Movement of the humerus towards the midline
in the transverse plane along its long axis
Subscapularis
INTERNAL ROTATION
INTERNAL ROTATION
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Pectoralis major (upper and lower)
Latissimus dorsi
Subscapularis
Teres major
EXTERNAL ROTATION
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Movement of the humerus away from the
midline in the transverse plane along its long
axis
EXTERNAL ROTATION
EXTERNAL ROTATION
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Supraspinatus
Teres minor