OIAN Flashcards
Deltoid
O: Anterior – lateral 1/3 of clavicle
Middle – acromion
Posterior – spine of scapula
I: deltoid tuberosity
A: shoulder abduction (after first 15%)
Anterior – flexion
Posterior – extension
N: axillary n (C5, C6)
B: posterior circumflex humeral artery
Teres major
O: inferior angle of scapula
I: medial lip of intertubercular groove
A: extension, internal rotation, adduction (assists latissimus dorsi)
N: lower subscapular n. (C5, C6)
B: subscapular a., Infrascapular a.
Rotator cuff
Supraspinatus
O: supraspinous fossa
I: greater tubercle of humerus
(superior facet)
A: first 15° of shoulder abduction
N: suprascapular nerve
B: suprascapular artery
Infraspinatus
O: infraspinous fossa
I: greater tubercle of humerus (middle facet)
A: external rotation
N: suprascapular nerve
B: suprascapular artery
Teres minor
O: lateral border of scapula
I: greater tubercle of humerus (inferior facet)
A: external rotation
N: axillary nerve
B: multiple, axillary a.
Subscapularis
O: subscapular fossa
I: lesser tubercle of humerus
A: internal rotation
N: upper and lower subscapular nn.
B: multiple, axillary a.
Trapezius
O: External occipital protuberance, Nuchal line, Spinous processes of C7-T12
Upper trap –
I: lateral 1/3 clavicle
A: acromion: elevates, upward rotates
neck: extends, lateral flexion, rotates
Middle trap –
I: acromion, spine
A: retracts scapula
Lower trap –
I: medial scapular spine
A: retract, depresses scapula
N: Spinal accessory nerve (CN XI) and C3, C4 ventral rami (proprioception)
The accessory nerve is particularly vulnerable to injury as it passes across the posterior triangle of the neck between the SCM and trap.
Latissimus dorsi
O: T7-T12, thoracolumbar fascia
I: floor of bicipital groove
A: extension, adduction, internal rotation
N: Thoracodorsal nerve (C6-C8)
B: Thoracodorsal artery
Axillary a. → subscapular a. → thoracodorsal a.
“Lady between 2 majors”
Levator scapulae
O: Transverse processes of C1-C4 vertebrae
I: Superior angle of scapula
A: Elevates, downward rotates scapula
N: Dorsal scapular (C5) and cervical (C3, C4) spinal nerves
Rhomboids
O: C6-T4
I: Medial border of scapula
A: retracts, downward rotation of scapula
N: Dorsal scapular nerve (C4, C5)
Pectoralis major
O: clavicle (medial half), sternum, costal cartilages 1-6, EO aponeurosis
I: humerus (lateral lip of intertubercular groove)
A: adduction, internal rotation, flexion, extension; inspiration (when shoulder is fixed)
N: medial & lateral pectoral nn. (C5-T1)
Pectoralis minor
O: ribs 3-5
I: coracoid process of scapula
A: depress, protract scapula, inspiration (with fixed scapula)
N: medial pectoral nn. (C8-T1)
Subclavius
O: rib 1
I: inferior surface of clavicle
A: supports clavicle, SC joint, Protects subclavian vessels and brachial plexus when clavicle is fractured
N: N. to subclavius
Serratus anterior
O: ribs 1-8
I: anterior surface of medial border of scapula
A: protracts scapula and holds against thoracic wall; rotates glenoid cavity superiorly
N: long thoracic n. (C5-C7)
Brachialis
O: humeral shaft (distal half)
I: ulnar tuberosity
A: elbow flexion
N: musculocutaneous n (C5, C6)
Coracobrachialis
O: coracoid process
I: humeral shaft (mid 1/3)
A: flexion and adduction of shoulder
N: musculocutaneous n (C5-C7)
Triceps brachii
O: long head - infraglenoid tubercle
lateral and medial head - humeral shaft
I: olecranon
A: elbow and shoulder extension
N: radial n (C6-C8)
Anconeus
O: lateral epicondyle of humerus
I: olecranon and posterior surface of ulna
A: assists with elbow extension, elbow stabilization
N: radial n (C7-T1)