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Deltoid
O -Inferior angle of the crest of the spine of the scapula, lateral margin of acromion, anterior border of lateral one-third of clavicle
I -Deltoid tuberosity of humerus
In -Axillary nerve [C5,C6]
F -Major abductor of arm (abducts arm beyond initial 15* done by supraspinatus); clavicular fibers assist in flexing the arm; posterior fibers assist in extending the arm
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Teres Major
O -Elongate oval area on the posterior surface of the inferior angle of the scapula
I -Medial lip of the intertubercular sulcus on the anterior surface of the humerus
In -Lower (inferior) subscapular nerve [C5,C6.C7]
F -Medial rotation, adduction, and extension of the arm at the glenohumeral joint
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Supraspinatus
O -Supraspinatus Fossa
I -Most superior facet on the greater tubercle of the humerus
In -Suprascapular nerve [C5,C6]
F -Rotator cuff muscle; initiation of abduction of arm to 15* at glenohumeral joint
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Infraspinatus
O -Infraspinatus Fossa
I -Middle facet on posterior surface of the greater tubercle of the humerus
In -Suprascapular nerve [C5,C6]
F -Rotator cuff muscle; lateral rotation of arm at the glenohumeral joint
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Teres Minor
O -Middle part of lateral border of scapula
I -Inferior facet on the posterior surface of the greater tubercle of the humerus
In -Axillary nerve [C5,C6]
F -Rotator cuff muscle; lateral rotation of arm at the glenohumeral joint
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Subscapularis
O -Subscapular fossa
I -Lesser tubercle of humerus
In -Upper & lower subscapular nerves [C5,C6,C7]
F -Rotator cuff muscle; medial rotation of the arm at glenohumeral joint
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Biceps brachii
O -Long head-supraglenoid tubercle of scapula; short head-apex of coracoid process
I -Radial tuberosity
In -Musculocutaneous nerve [C5,C6]
F -Powerful flexor of the forearm at the elbow joint and supinator of the forearm; accessory flexor of the arm at glenohumeral joint
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Triceps brachii
O -Long head-infraglenoid tubercle of scapula; medial & lateral heads-posterior surface of humerus
I -Olecranon
In -Radial nerve [C6,C7,C8]
F -Extension of the forearm at elbow joint. Long head can also extend & adduct the arm at glenohumeral joint
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Coracobrachialis
O -Apex of coracoid process
I -Linear roughening on midshaft of humerus on medial side
In - Musculocutaneous nerve [C5,C6,C7]
F -Flexor of the arm at glenohumeral joint
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Brachialis
O -Anterior aspect of humerus (medial & lateral surfaces) & adjacent intermuscular septae
I -Tuberosity of ulna
In - Musculocutaneous nerve [C5,C6]; (small contribution by radial nerve [C7] to lateral part of muscle)
F -Powerful flexor of the forearm at elbow joint
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Brachioradialis
O -Proximal part of lateral supraepicondylar ridge of humerus & adjacent intermuscular septum
I -Lateral surface of distal end of radius
In -Radial nerve [C5,C6] before division into superficial & deep branches
F -Accessory flexor of elbow joint when forearm is midpronated
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