Attachments for

deltoideus m.

Origin: spine of scapula and acromion

Termination: deltoid tuberosity of humerus

Actions of

deltoideus m. 

Attachments for

teres minor m. 

Origin: caudal border of scapula

Termination: teres minor tuberosity of humerus (lateral, proximal, on tricipital line)

Actions of

teres minor m.

Attachments for

supraspinatus m.

Origin: supraspinous fossa of scapula

Termination: greater tubercle of humerus

Actions of

supraspinatous m.

Extend humeral joint

(Major extensor of humeral joint)

(Acts as lateral collateral ligament of humeral joint)

 Attachments for

infraspinatous m.

Origin: infraspinous fossa of scapula

Termination: greater tubercle of humerus

Actions of

infraspinatous m.

Depending on position of limb, will

- flex humeral joint

- abduct limb at humeral joint

(Acts as lateral collateral ligament of humeral joint)

(Only abductor of the thoracic limb.)

Attachments for

subscapularis m.

Origin: subscapular fossa of scapula

Termination: lesser tubercle of humerus

Actions of

subscapularis m.

Adduct limb at humeral joint

(Acts as medial collateral ligament of humeral joint)

Attachments for

teres major m.

Origin: caudal border of scapula

Termination: teres major tuberosity of humerus

(Medial, proximal 1/3)

Actions of

teres major m.

Flex humeral joint

(Major flexor of humeral joint)

Attachments for

coracobrachialis m.

Origin: coracoid process of scapula

Termination: crest of lesser tubercle of humerus

Actions of

coracobrachialis m.

Adduct limb at shoulder

(Acts as medial collateral ligament of humeral joint)

Attachments for

biceps brachii m.

Origin: supraglenoid tubercle of scapula

Termination: radial / ulnar tuberosities

Actions of

biceps brachii m.

Flex cubital joint

Extend humeral joint

(Major flexor of cubital joint)

Attachments for

brachialis m.

Origin: humerus

Termination: radius and/or ulna

Actions of

brachialis m.

Attachments for

tensor fasciae antebrachii m.

Origin:  lattisimus dorsi and fascia on caudal border of scapula

Termination: tuber olecrani (ulna)

Actions of

tensor fasciae antebrachii m.

Extend cubital joint

(tense deep antebrachial fascia)

Attachments for

anconeus m.

Origin:  caudal aspect of distal humerus

Termination:  tuber olecrani (ulna)

Actions of 

anconeus m.

Attachments for

triceps brachii m.

Origin:  

Long head: caudal border of scapula

Medial, lateral, accessory heads: proximal humerus

Termination: tuber olecrani (ulna)

Actions of

triceps brachii m.

Long, medial, lateral, accessory heads:  extend cubital joint

Long head: flex humeral joint

(Major extensor of cubital joint)