Muscles Inserting on Upper Humerus

Question 1

Pec Major: Origin and Insertion

Answer 1

Origin: Medial part of clavicle, sternum, costal cartilages of ribs and upper rectus sheath

Insertion: Crest of greater tubercle

Question 2

Pec Major: Action and Innervation

Answer 2

Adducts and Medially rotates arm

Innervated by medial and lateral pectoral nerves

Question 3

Deltoid: Origin and Insertion

Answer 3

Origin: Lateral 1/3 of clavicle, lateral acromion and crest spine of scapula

Inserts: Deltoid Tuberosity

Question 4

Deltoid: Action and Innervation

Answer 4

Abducts arm

Innervated by axillary nerve

Question 5

Latissimus Dorsi: Origin and Insertion

Answer 5

Origin: Spinous processes of lower thoracic vertebrae, spinous processes of lumbar vertebrae, dorsum of sacrum, iliac crest and lower ribs

Inserts: On crest of lesser tubercle and intertubercular sulcus

Question 6

Latissimus Dorsi: Action and Innervation

Answer 6

Extends, adducts and medially rotates the arm

Innervated by thoracodorsal nerve/middle subscapular nerve

Question 7

Teres Major: Origin and Insertion

Answer 7

Origin: Inferior angle and axillary border of scapula

Inserts: Crest of lesser tubercle

Question 8

Teres Major: Action and Innervation

Answer 8

Adducts and medially rotates arm

Innervated by lower subscapular nerve