16 muscles attached to scapula Flashcards
levator scapulae
O: poterior tubercles of the transverse process of the upper 3 or 4 cervical vertebrae
I: superior angle of scapula at and above the scapular spine
A: 1.) elevates the scapula, 2.) extends and/or laterally flexes the neck, 3.) assists to downwardly rotate the scapula
B: transverse cervical artery
N: 1.) nerves off cervical plexus C3, 4
2.) dorsal scapular nerve, C5
Rhomoid Minor
O: spine process of C7 and T1, lower part of the ligament nuchal, supraspinous ligmament
I: medial margin of the scapula at the root of the spine
A: retracts and stabilizes the scapula, assists to downwardly rotate the scapula, assists to adduct the arm
B: deep branch of transverse cervical artery or dorsal scapular artery
N: dorsal scapular nerve, C5
Rhomboid Major
O: spine processes of T2-T5, supraspinous ligament
I: medial scapula from the scapular spine to the inferior angle
A: retracts and stabilizes the scapula, assists to downwardly rotate the scapula, assists to adduct the arm
B: deep branch of transverse cervical artery, dorsal scapular artery
N: dorsal scapular nerve, C5
serratus anterior
O: outer sufaces and superior borders of the upper 8 or 9 ribs
I: costal aspect of medial margin of the scapula
A: protracts the scapula, stabilizes the scapula (preventing winging of the scapula), assists to upwardly rotate the scapula
B: lateral thoracic artery supplies the upper part, thoracodorsal artery supplies the lower part
N: long thoracic nerve C5, 6,7
deltoid
O: anterior portion: anterior border of the lateral 1/3 of the clavicle, middle portion: lateral border of the accordion process of the scapula, posterior portion: scapular spine
I: deltoid tuberosity, on the lateral surface of the shaft of the humerus
A: anterior portion: flexes and internally rotates the arm, middle portion: abducts the arm, posterior portion: extends and externally (laterally) rotates the arm
B: posterior humeral circumflex artery, deltoid branch of thoracoacromial artery
N: axillary nerve
supraspinatus
O: supraspinous fossa of the scapula
I: uppermost of three facets of the greater tubercle of humerus, capsule of the shoulder joint
A: abducts the arm, stabilizes the glenohumeral joint
B: suprascapular artery (poorly supplied)
N: suprascapular nerve, C5,6
infraspinatus
O: infraspinous fossa of the scapula
I: middle facet of greater tubercle of humerus, capsule of the shoulder joint
A: externally rotates the arm, stabilizes the glenohumeral joint
B: suprascapular artery, scapular circumflex artery
N:suprascapular nerve, C5,6
Teres Minor
O: middle half of the scapula’s lateral margin
I: lowest of three facets of the greater tubercle of humerus, capsule of the shoulder joint
A: externally rotates the arm, stabilizes the glenohumeral joint
B: scapular circumflex artery
N: axillary nerve, C5,6
Teres Major
O: lower third of the posterior surface of the lateral margin of the scapula
I: medial lip of the bicipital groove of the humerus (just medial to the insertion of latissimus dorsi)
A: internally rotates the arm, extends the arm (from flexed position), adducts the arm
B: throacodorsal artery
N: lower sub scapular nerve, C5, 6
Subscapularis
O: subscapular fossa on the anterior surface of the scapula
I: lesser tubercle of the humerus, lower part of the capsule of the shoulder joint
A: internally rotates the arm, stabilizes the glenohumeral joint
B: branches of sub scapular artery
N: upper and lower sub scapular nerves C5, 6
pectoralis minor
O: outer surface of ribs 3-5
I: medial aspect of coracoid process of the scapula
A: depresses the scapula, downwardly rotates the scapula, assists to protect the scapula from a retracted position, stabilizes the scapula
B: lateral thoracic artery
N: medial pectoral nerve, C8, T1
coracobrachialis
O: coracoid process of the scapula
I: medial shaft of the humerus at about its middle
A: flexes the humerus, assists to adduct the humerus
B: muscular branches of the brachial artery
N: musculocutaneous nerve C5, 6
Biceps Brachii
O: long head- supraglenoid tubercle and glenohumeral labrum, short head- tip of the coracoid process of the scapular
I: radial tuberosity, biciptal aponeurosis
A: flexes the forearm at the elbow (when supinated, supinates forearm from neutral, stabilizes anterior aspect of shoulder, flexes shoulder
B: muscular branches of brachial artery
N: musculocutaneous nerve C5,6
Triceps brachii (long head)
O: long head- infraglenoid tubercle of the scapula
I: posterior surface of the olecranon process of the ulna, deep fascia of the ante brachium
A: long head- extends the forearm at the elbow, adducts the arm, may extend the shoulder from a flexed position
B: muscular branches of the brachial artery, superior ulnar collateral artery, profunda brachii artery
N: radial nerve, C7,8
omohyoid (inferior belly)
O: inferior belly- superior scapular border (medial to suprascapular notch)
I: both bellies meet at the clavicle and are held to the clavicle by a pulley tendon
A: depress hyoid and larynx, acts eccentrically with the supra hyoid muscles to provide them a stable base
B: inferior thyroid artery (primary), superior thyroid artery
N: inferior root of the nasa cervicalis, C2,3
