Muscles of the shoulder and arm

retraction of scapula

Move medial border towards the vertebral column

Protraction of scapula

Moving medial border away from the vertebral column

elevation of scapula

Pulling scapula superiorly (shrugging shoulders)

Depression of scapula

Pulls scapula inferiorly/down

Rotation of scapula

Changing angle of glenoid cavity

Muscles from the Axial Skeleton to the Pectoral Girdle-Posterior

Trapezius, Levator scapulae, Rhomboid major, and Rhomboid minor

Trapezius muslce

-O: Superior nuchal line, external occipital protuberance, ligamentum nuchae, and spinous processes of C7 and T1-T12
-I: Lateral 1/3 of clavicle, acromion, and spine of scapula
-A: Elevates, retracts, and depress scapula
-Inn: Accessory n (CN XI)

Levator scapulae

-O: Vertebrae
-I: Scapula
-A: Elevates scapula
-In neck area

Rhomboid minor

-O: Vertebrae
-I: Scapula
-A: Retracts scapula
-Smaller and superior

Rhomboid major

-O: Vertebrae
-I: Scapula
-A: Retracts scapula
-Bigger and inferior

Muscles from the Axial Skeleton to the Pectoral Girdle -Anterior

Serratus anterior and pectoralis minor

Serratus anterior

-O: Lateral surface of ribs 1-8
-I: Anterior surface of medial (vertebral) border of scapula
-A: Protracts scapula, holds scapula against thoracic wall, and rotates scapula
-Inn: Long thoracic n
-"Boxers muscle"

Pectoralis minor

-O: Ribs
-I: Coracoid process of scapula
-A: Protracts scapula and elevates ribs when the scapula is stationary to assist in inhalation

Paralysis of what muscle results in "winging of the scapula"?

Serratus anterior

Damage to what nerve will give you "winged scapula'."?

long thoracic nerve

Muscles from axial skeleton to humerus

pectoralis major and latissimus dorsi

Pectoralis major

-O: Medial half of clavicle, sternum, and costal cartilage of ribs 2-6
-I: Greater tubercle of humerus
-A: Adducts and medially rotates arm (shoulder)
-Inn: medial pectoral n and lateral pectoral n
-Front of chest

Latissimus dorsi

-O: Spinous processes of T7-T12, thoracolumbar fascia, and iliac crest
-I: Floor of intertubercular sulcus (bicipital groove) of humerus
-A: Adducts, extends, and medially rotates arm (shoulder)
-Inn: Thoracodorsal n

Muscles from the Pectoral Girdle to Humerus

Subscapularis, supraspinatus, infraspinatus, teres minor, teres major, and deltoid

What muscles are rotator cuff muscles?

Subscapularis, supraspinatus, infraspinatus, and teres minor

Subscapularis

-O: Subscapular fossa of scapula
-I: Humerus
-A: Medially rotates arm (shoulder)

Supraspinatus

-O: Supraspinous fossa of scapula
-I: Humerus
-A: Abducts arm (shoulder)
-Inn: Suprascapular n
-Responsible for first 30 degrees of abduction of arm

Infraspinatus

-O: Infraspinous fossa of scapula
-I: Humerus
-A: Laterally rotates arm (shoulder)

Teres minor

-O: Scapula
-I: Humerus
-A: Laterally rotates arm (shoulder)
-Inn: Axillary n

Mnemonic for Rotator Cuff muscles

Sits

functions of rotator cuff muscles

-Provide stability for the joint
-Help hold the head of humerus in the joint

What would happen if you cause trauma to the rotator cuff muscles?

The glenohumeral joint would be destabilized and more prone to dislocation

Teres major

-O: Scapula
-I: Humerus
-"Latt's little helper" (does same things as latissimus dorsi)

Deltoid

-O: Lateral 1/3 of clavicle, acromion, and spine of scapula
-I: Deltoid tuberosity of humerus
-A: Anterior part=Flexes and medially rotates arm
Middle part= Abducts arm
Posterior part= Extends and laterally rotates arm
-Inn: axillary n

Muscles of anterior compartment of the arm

coracobrachialis, biceps brachii (long and short head), brachialis

Compartment rule for anterior arm muscles

-A: flexors (of what depends on what joint they cross)
-Inn: Musculocutaneous n

Biceps brachii

-O: Short head= Coracoid process of scapula
Long head= Supraglenoid tubercle of scapula (runs through intertubercular sulcus)
-I: Radial tuberosity and deep fascia of forearm via bicipital aponeurosis
-A: Flexes forearm when forearm is supinated, supinates forearm, and slight arm flexion
-Inn: Musculocutaneous n

Coracobrachialis

-O: Coracoid process of scapula
-I: Middle of humerus (medial side)
-A: Flexes and adducts arm (shoulder)
-Inn: Musculocutaneous n

Brachialis

-O: Distal half of anterior surface of humerus
-I: Ulnar tuberosity (front of ulna)
-A: Flex forearm (elbow)
-Inn: Musculocutaneous n
-Major flexor of forearm

Muscles of posterior arm

Triceps brachii (Long, lateral, and medial head)

Compartment rule of posterior arm

-A: major extensor
-Inn: Radial n
-I: Olecranon process of ulna

triceps brachii long head

-O: Infraglenoid tubercle of scapula
-I: Olecranon process of ulna
-A: Extends forearm
-Inn: Radial n

Triceps brachii lateral head

-O: Posterior surface of humerus superior to radial groove
-I: Olecranon process of ulna
-A: extends forearm
-Inn: Radial n

Triceps brachii medial head

-O: Posterior surface of humerus inferior to radial groove
-I: Olecranon process of ulna
-A: extends forearm
-Inn: Radial n

What is the strongest flexor of forearm?

brachialis

What is the strongest abductor of the arm?

Deltoid

What muscle is responsible for helping you climb and is also the strongest extensor of the arm?

Latissimus dorsi

What muscle does the most work for shrugging your shoulders?

Trapezius