Download The Shoulder Complex - PA

The Shoulder Joint
TEST MONDAY
Anterior Shoulder Muscles
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Coracobrachialis
Pectoralis Major
Subscapularis
Biceps Brachii
Biceps Brachii
• Origin
• Short head: coracoid
process of scapula
Long head:
supraglenoid tubercle of
scapula
• Insertion Tuberosity of
radius
• Action Flexion of the
elbow and shoulder,
Supinates forearm
• ***the long head is the
“5th rotator cuff”
Coracobrachialis
• O: Coracoid process
• I: Anteromedial
surface of midshaft of
humerus
• Actions: (WEAK!)
– Flexion
– Adduction of the
shoulder
Pectoralis Major
• Origin:
– Medial two-thirds of clavicle
– Sternum
• Insertion: intertubercular groove
• Actions
– Upper fibers (Clavicular)
• Flexion
• Horizontal Adduction
– Lower fibers (Sternal)
• Internal/medial Rotation
• Horizontal adduction
Subscapularis
• O: Subscapular fossa
• I: Lesser tubercle and
crest of humerus
• Actions:
– Internal Rotation
• Stabilization
• Anterior Rotator Cuff
Muscle.
Superior Shoulder Muscles
• Deltoid
• Supraspinatus
Deltoid
• Origin
– Lateral 1/3 of clavicle
(Anterior fibers)
– Acromion process (Middle fibers)
– Spine of scapula
(Posterior fibers)
• Insertion – deltoid tuberosity
Actions
Anterior –Flexion
Middle – Abduction
Posterior –Extension
Supraspinatus
• O: Supraspinous
fossa
• I: Greater tubercle
• Action:
– Abduction
• Stabilization
• Superior Rotator Cuff
Muscle.
• Most injured rotator
cuff muscle
Inferior Shoulder Muscles
• Latissimus Dorsi
• Teres Major
Latissimus Dorsi
• O: Spinous process of
lower 6 thorasic and
all lumbar and sacral
vertebrae; iliac crest
• I: Intertubercular
groove
• Actions:
– Adduction
– Internal Rotation
Teres Major
• O: Inferior angle of
scapula
• I: Intertubercular
groove
• Actions:
– Adduction
– Internal rotation
• “Lats little helper”
Posterior Shoulder Muscles
• Infraspinatus
• Teres Minor
• Triceps Brachii
Triceps Brachii
• Origin
Long head: infraglenoid
tubercle of scapula
Lateral head: posterior
surface of humerus,
Medial head: posterior
surface of humerus,
Insertion Olecranon process
of ulna
• Action Chief extensor of
elbow (long head extends
the shoulder)
Infraspinatus
• O: Infraspinous fossa
• I: Greater tubercle
• Actions:
– External rotation
• Stabilization
• Posterior Rotator Cuff Muscle
• Second most commonly
injured rotator cuff muscle
Teres Minor
• O: lateral border of
scapula
• I: Greater tubercle
• Actions:
– External rotation
• Stabilization
• Posterior Rotator Cuff
Muscle
Muscles of the scapula only
Trapezius
• Origin occipital bone,
nuchal ligament, and
spinous processes of
C7 - T12 vertebrae
• Insertion Lateral third
of clavicle, acromion,
and spine of scapula
• Action
• superior fibers elevate,
• middle fibers retract,
• inferior fibers depress
scapula;
Levator Scapula
• Origin C1 - C4
vertebrae
• Insertion Superior
angle
• Action Elevates
scapula
Rhomboid major and minor
Rhomboid major and minor
• Origin
Minor: spinous
processes of C7 and T1
vertebrae
Major: spinous
processes of T2 - T5
vertebrae
• Insertion Medial border
of scapula
• Action Retract scapula
Serratus Anterior
• Origin the eight
upper frontal ribs
• Insertion lateral
border of scapula
• Action protracts
scapula
Name the muscle.
Coracobrachialis
Name the action
Flexion and
Adduction of
the shoulder
Name the muscle.
Pectoralis Major
Function
Horizontal Adduction
Internal roatation
Name the muscle.
Subscapularis
Name the action
Internal
rotation of the
shoulder
Name the muscle.
Deltoid
Name the action
Abduction of shoulder (middle
third)
Flexion (anterior deltoid)
Extension (posterior deltoid)
Name the muscle.
Infraspinatus
Name the action
External
rotation
Name the muscle.
Name the action
Teres Major
Adduction of
arm
Name the muscle.
Teres Minor
Name the action if the humerus move directly to the posterior
Extension of the shoulder
Name the muscle.
Supraspinatus
Name the action
Abduction of the shoulder
Coracobrachialis
Subscapularis
Pect. Major
Deltoid
Supraspinatus
Teres Major
Infraspinatus
Teres Minor