Muscle Actions and Innervation of the Scapula and Shoulder

Elevates scapula

Levator scapula, Upper trapezius, Rhomboid major/minor

Depresses scapula

Lower trapezius, Pectoralis minor

Upward rotation of scapula

Upper trapezius, Lower trapezius, Serratus anterior

Downward rotation of scapula

Pectoralis minor

Abducts/Protracts scapula

Pectoralis minor, Serratus anterior

Adducts/Retracts scapula

Rhomboid major/minor, Middle trapezius

Scapular tipping

Pectoralis minor

Rotates/Laterally flexes head/neck (same side)

Splenius capitis, Splenius cervicis

Extends head and neck

Splenius capitis, Splenius cervicis, Suboccipitals

Shoulder flexion

Anterior deltoid, Lateral deltoid

Shoulder extension

Posterior deltoid, Latissimus dorsi

Shoulder abduction

Supraspinatus (initiates), Deltoid

Shoulder adduction

Teres major, Pectoralis major, Latissimus dorsi

Shoulder horizontal abduction

Posterior deltoid

Shoulder horizontal adduction

Anterior deltoid

Shoulder external rotation

Infraspinatus, Teres minor

Shoulder internal rotation

Teres major, Subscapularis, Pectoralis major, Lat dorsi

Spinal accessory nerve

All parts of trapezius

Thoracodorsal nerve

Latissimus dorsi

Dorsal scapular nerve

Rhomboid major/minor, Levator scapula

Suboccipital nerve

Obliquus capitis inferior/superior, Rectus capitis post. major/minor

Dorsal ramus

Erector spinae: iliocostalis, longissimus, spinalis

Axillary nerve

Deltoid (all parts), Teres minor

Suprascapular nerve

Supraspinatus, Infraspinatus

Upper subscapular nerve

Subscapularis, Teres major

Lower subscapular nerve

Long thoracic nerve

Medial pectoral nerve

Pectoralis major, Pectoralis minor

Lateral pectoral nerve

Pectoralis major