Shoulder Muscles (origins, insertions, actions, innervation) Flashcards
Trapzius: Insertion
Posterior 1/3 clavicle
Medial border acromion; upper border scapular spine
Triangular space base of scapular spine
Trapezius: Origin
External occipital protuberance; Ligamentum nuchae
Spinous C7-T3
Spinous T4-T12
Trapezius: Actions
Elevation scapula
Retraction scapula
Upward rotation scapula
Depression scapula
Trapezius: Innervation
Accessory Nerve (CN XI)
Latissimus dorsi: Origin
Spinous T6-T12
Lumbar and sacral vertebrae
Posterior iliac crest
Latissimus dorsi: Insertion
Medial lip and floor of intertubercle groove of humerus
Latissimus dorsi: Actions
Extension arm
Adduction arm
Internal rotation glenohumeral
Horizontal abduction glenohumeral
Latissimus dorsi: Innervation
Thoracodorsal nerve
(C6-C8)
Brachial plexus: Posterior
Levator scapulae: Origin
Transverse process C1-C4
Levator scapulae: Insertion
Superior angle-Medial border scapula above spine base
Levator scapula: Actions
Elevate scapula
downward rotate/adduction
Levator scapulae: Innervation
Dorsal scapular nerve (C5)
(C3,C4)
Rhomboid minor: Origin
Lower ligamentum nuachae
Spinous C7-T1
Rhomboid minor: Insertion
Medial border scapula base of spine
Rhomboid minor: Actions
Elevation scapula
Retraction scapula
Downward rotation glenohumeral
Rhomboid minor: Innervation
Dorsal scapular nerve
(C5)
Rhomboid major: Origin
Spinous T2-T5
Rhomboid major: Insertion
Medial border scapula below minor
Rhomboid major: Actions
Elevation of scapula
Retraction of scapula
Downward roation glenohumeral
Rhomboid major: Innervation
Dorsal scapular nerve
(C5)
Serratus anterior: Origin
Anterior Ribs 1-8
Anteriolateral thoracic wall
Serratus anterior: Insertion
Inferior angle: anterior medial border scapula
Serratus anterior: Actions
Protraction of scapula
Upward rotation glenoid cavity
Holds medial border against thoracic
Serratus anterior: Innervation
Long thoracic nerve
(C5-C7)
Deltoid: Origin
Anteriolateral 1/3 clavicle
Lateral aspect of acromion
Inferior spine of scapula
Deltoid: Insertion
Deltoid tuberosity of humerus
Deltoid: Actions
Flexion/Internal rotation of arm (horiz/diag add)
Abduction (horiz abd)
Extension/External rotation of arm (horiz/diag abd)
Deltoid: Innervation
Axillary nerve
(C5,C6)
Brachial Plexus: Posterior
Sternocleidomastoid: Origin
Sternum (tendinous head)
Medial 1/3 clavicle (muscular head)
Sternocleidomastoid: Insertion
Mastoid of skull
Sternocleidomastoid: Actions
Head flexion same side
Head internal rotation
Sternocleidomastoid: Innervation
Accessory nerve (CN XI)
Subclavius: Origin
1 Rib
Subclavius: Insertion
Undersurface clavicle
Subclavius: Actions
Depress clavicle
Maintain sternoclavicular joint
Subclavius: Innervation
Nerve to subclavius
(C5,C6)
Supraspinatus: Origin
Medial 2/3 supraspinous fossa
Supraspinatus: Insertion
Superior greater tubercle of humerus
Supraspinatus: Action
Abduction of arm
Supraspinatus: Innervation
Suprascapular nerve
(C5,C6)
*Brachial Plexus: Upper *
Infraspinatus: Origin
Medial infraspinatus fossa
Infraspinatus: Insertion
Greater tubercle of humerus below supraspinatus
Infraspinatus: Actions
Extension of arm
External rotation of arm
(Horiz/diag abd arm)
Infraspinatus: Innervation
Suprascapular nerve
(C5,C6)
Brachial Plexus: Upper
Teres minor: Origin
Upper 2/.3 lateral border scapula
Teres minor: Insertion
Greater tubercle of humerus below infraspinatus
Teres minor: Actions
Extension arm
External rotation of arm
(horiz/diag abd of arm)
Teres minor: Innervation
Axillary nerve
(C5,C6)
Brachial Plexus: Posterior
Teres major: Origin
Posterior inferior angle of scapula
Teres major: Insertion
Medial lip intertubicular groove
Teres major: Actions
Extension of arm
Internal rotation of arm
Adduction of arm
Teres major: Innervation
Lower subscapular nerve
(C5,C6)
Brachial plexus: Posterior
Subscapularis: Origin
Subscapular fossa of anterior scapula
Subscapularis: Insertion
Lesser tubercle (crest) of humerus
Subscapularis: Actions
Internal rotation of arm
- Extension of arm*
- Adduction of arm*
Subscapularis: Innervation
Upper and lower subscapular nerve
(C5,C6)
Brachial Plexus: Posterior
Pectoralis major: Origin
Medial anterior 1/3 clavicle
Anterior costal cartilate rib 1-6
Sternum
Pectoralis major: Insertion
Lateral lip intertubicular groove
(crest greater tubercle)
Pectoralis major: Actions
Internal rotation, Adduction
Flexion (clavicular fibers)
Extension (sternocostal fibers)
horiz/diag add
Pectoralis major: Innervation
Medial pectoralis nerve (C8, T1): Medial
Lateral pectoralis nerve (C5-C7): Lateral
Pectoralis minor: Origin
Anterior ribs 3-5
Pectoralis minor: Insertion
Coracoid process of scapula
Pectoralis minor: Actions
Depress shoulder
Down rotation of scapula
Abduct
Pectoralis minor: Innervation
Medial pectoralis nerve
(C8, T1)
Brachial Plexus: Medial