Shoulder Muscles Table.docx

Muscle Pectoralis major

Proximal Attach

Distal Attach

Clavicular head: anterior surface, medial ½ clavicle Sternocostal head: anterior sternum, superior 6-7 costal cartilages

Lateral lip of intertubercular sulcus

Pectoralis minor

Ribs 3-5

Coracoid process

Subclavius

Clavicle

Ribs 1-8(9)

Serratus anterior

Action -

Lateral and medial pectoral nerves

-

Protract scapula Inferior rotation of scapula

Medial pectoral nerve

Costal cartilage of 1st rib

-

Nerve to subclavius

Anterior side of medial border of scapula

-

Anchor clavicle Depress lateral end of clavicle Keep scapula away from thoracic wall Protract scapula Superior rotation of scapula during abduction Descending part: elevate scapula Ascending part: Depress scapula Middle part: retract scapula Superior/Inferior: rotate scapula superiorly during abduction Extend, medially rotate, adduct arm Elevate, inferiorly rotate scapula Retract, elevate, inferior rotate scapula Central part: abduct arm Anterior part: flext, medial rotate arm

-

-

Trapezius

External occipital protuberance, superior nuchal line, nuchal ligament, spinous processes C7-T12

Lateral 1/3 clavicle, acromion, scapular spine

-

Levator scapulae

Spinous processes T7-L5, sacrum, PSIS Transverse process C1-4

Rhomboid major/minor

Spinous processes C7-T5

Deltoid

Lateral 1/3 clavicle, acromion, scapular spine

Latissimus dorsi

Innervation

Adduct, medial rotate humerus Clavicular head extends humerus Sternocostal head extends humerus if already flexed

Intertubercular sulcus of humerus Superior scapular angle, base of scapular spine Medial angle of scapula (at level, or below scapular spine) Deltoid tuberosity of humerus

-

-

Other Notes 1/3 muscles in the intertubercular area

Long thoracic nerve

Cranial Nerve XI (accessory nerve)

Blood supply: transverse cervical artery

Thoracodorsal nerve

1/3 muscles in intertubercular area Blood: transverse cervical a.

Dorsal scapular nerve Dorsal scapular nerve

Axillary nerve

Deltopectoral triangle

-

Supraspinatus

Supraspinous fossa

Greater tubercle of humerus superiorly (under acromion)

-

Infraspinatus

Infraspinous fossa

Greater tubercle of humerus, middle part

-

Teres minor

Lateral border of scapula

Greater tubercle of humerus inferiorly

-

Teres major Subscapularis

Major Landmarks: Landmark Deltopectoral Triangle

Quadrangular Space

Triangular Space

Triangular Interval

Inferior angle of scapula Subscapular fossa

Lesser tubercle of humerus, posterior to latissimus dorsi Lesser tubercle of humerus

Borders Deltoid, Pectoralis major, clavicle Teres major inferior Teres minor superior Humerus lateral Long head triceps medial Teres major Teres minor Long head of triceps Long head triceps Shaft of humerus Teres major

-

Posterior part: extend, laterally rotate arm Initiates abduction Stabilize shoulder joint Lateral rotate humerus Stabilize shoulder joint Lateral rotate humerus Stabilize shoulder joint Adduct, extend, medially rotate arm Medial rotate arm Stabilize shoulder joint

What’s Inside/Around? Cephalic vein Deltoid branch Thoracoacromial artery Axillary nerve Posterior circumflex humeral artery Circumflex scapular vessels

Radial nerve Profunda brachii artery

Suprascapular nerve

Part of SITS muscles Blood: suprascapular a.

Suprascapular nerve

Part of SITS muscles Blood: suprascapular a.

Axillary nerve

Part of SITS muscles; hard to separate from infraspinatus

Lower subscapular nerve

1/3 muscles in intertubercular area Part of SITS muscles

Upper and lower subscapular nerves

Notes Coracoid process palpated deeply within triangle