C - Axioappendicular Muscles Moving the Humerus

Superficial Muscles Characteristics

• large moment arms

• good at generating large movements at the joints they cross

Superficial Muscles

• pectoralis major

• deltoid

• latissimus dorsi

• teres major

Rotator Cuff Muscles Characteristics

• small moment arms

• provide stabilizing the GH joint but translating the humerus medially against the scapula

• deep muscles

Rotator Cuff Muscles

• supraspinatus

• infraspinatus

• teres minor

• subscapularis

Pectoralis Major (sternum) - origin, insertion, action, innervation

• O - sternum and costal cartilages 1-6

• I - intertubular groove (lateral)

• A - adduction, internal rotation, extend from flexion'

• In - medial and lateral pectoral nerves

Pectoralis Major (clavicle) - origin, insertion, action, innervation

• O - medial clavicle

• I - intertubercular groove (lateral)

• A - adduction, internal rotation, flexion

• In - medial and lateral pectoral nerves

Anterior Deltoid - origin, insertion, action, innervation

• O - lateral clavicle, acromion, and scapular spine

• I - deltoid tuberosity

• A - flexion, internal rotation

• In - axillary nerve

Middle Deltoid - origin, insertion, action, innervation

• O - lateral clavicle, acromion, and scapular spine

• I - deltoid tuberosity

• A - abduction

• In - axillary nerve

Posterior Deltoid - origin, insertion, action, innervation

• O - lateral clavicle, acromion, and scapular spine

• I - deltoid tuberosity

• A - extension, external rotation

• In - axillary nerve

Latissimus Dorsi - origin, insertion, action, innervation

• O - SPs T7 - T12, iliac crest

• I - intertubercular groove

• A - extension, adduction, internal rotation

• In - thoracodorsal nerve

Teres Major - origin, insertion, action, innervation

• O - inferior angle

• I - intertubercular groove

• A - adduction, internal rotation

• In - lower subscapular nerve

Supraspinatus - origin, insertion, action, innervation

• O - supraspinous fossa

• I - greater tubercle of humerus

• A - abduction

• In - suprascapular nerve

Infraspinatus - origin, insertion, action, innervation

• O - infraspinous fossa

• I - greater tubercle

• A - anchors humerus, external rotation

• In - suprascapular nerve

Teres Minor - origin, insertion, action, innervation

• O - lateral border

• I - greater tubercle

• A - anchors humerus, external rotation

• In - axillary nerve

Subscapularis - origin, insertion, action, innervation

• O - subscapular fossa

• I - lesser tubercle

• A - anchors humerus, internal rotation

• In - upper and lower subscapular nerves