Arm & Elbow

Question 1

Trapezius

Answer 1

Origin: Superior nuchal line, occipital protuberance, spinous process of C7-T12 vertebrae

Insertion: clavicle, acromion and spine of scapula

Innervation: accessory nerve (C11)

Action: Superior: elevates. Inferior: depresses. Middle part: retracts scapula

Question 2

Deltoid

Answer 2

Origin: inferior spine of scapula, lateral margins of acromion, anterior border of lateral clavicle

Insertion: deltoid tuberosity of humerus

Innervation: axillary nerve (C5, C6)

Action: Anterior part: flexes and medially rotates arm. Middle part: abducts arm. Posterior part: extends and laterally rotates arm

Question 3

Levator Scapulae

Answer 3

Origin: Transverse processes of C1-C4 vertebrae

Insertion: superior angle of scapula

Innervation: dorsal scapular (C5) and cervical (C3, C4)

Action: Elevates scapula and tilts its glenoid cavity by rotating the scapula

Question 4

Rhomboids

Answer 4

Origin: Minor: spinous processes of C7 and T1 vertebrae. Major: spinous process of T2-T5 vertebrae

Insertion: Minor: medial border of scapula above scapular spine. Major: medial border of scapula below scapular spine

Innervation: Dorsal scapular nerve (C4, C5)

Action: Retract scapula and rotate it to depress glenoid cavity, fix scapula to thoracic wall

Question 5

Supraspinatus

Answer 5

Origin: supraspinatus fossa of scapula

Insertion: greater tubercle of humerus

Innervation: Suprascapular nerve (C5, C6)

Action: Arm abduction/ rotator cuff

Question 6

Infraspinatus

Answer 6

Origin: infraspinatus fossa of scapula

Insertion: Greater tubercle of humerus

Innervation: Suprascapular nerve (C5, C6)

Action: Laterally rotate arm/ rotator cuff

Question 7

Teres Minor

Answer 7

Origin: lateral border of scapula

Insertion: greater tubercle of humerus

Innervation: axillary nerve (C5, C6)

Action: laterally rotate arm/ rotator cuff

Question 8

Teres Major

Answer 8

Origin: inferior angle of scapula

Insertion: Intertubercular groove of humerus

Innervation: lower subscapular nerve (C5, C6)

Action: extension, adduction, and internal rotation of the arm

Question 9

Long Head of Triceps

Answer 9

Origin: infraglenoid tubercle on scapula

Insertion: olecranon of the ulna

Innervation: radial nerve (c6-C8)

Action: extension of the elbow and adduction of the shoulder and extension of arm

Question 10

Pectoralis Major

Answer 10

Origin: Clavicular head- anterior surface of clavicle. Sternocostal head- anterior surface of sternum, first 7 costal cartilages

Insertion: lateral lip of intertubercular sulcus of humerus

Innervation: Clavicular head- medial and lateral pectoral nerves (C5, C6)

Action: flexion, adduction and medial rotation of arm

Question 11

Subclavius

Answer 11

Origin: first rib and its costal cartilage

Insertion: middle one-third of clavicle

Innervation: nerve to subclavius (C5-C6)

Action: depresses the clavicle down forward

Question 12

Pectoralis Minor

Answer 12

Origin: ribs 3-5

Insertion: coracoid process of scapula

Innervation: medial pectoral nerve (C8-T1)

Action: elevates the ribs and draws the scapula down and medially

Question 13

Serratus Anterior

Answer 13

Origin: 1-9 ribs

Insertion: costal surface of medial border of scapula

Innervation: long thoracic nerve (C5-C7)

Action: protraction and rotation of the scapula

Question 14

Subscapularis

Answer 14

Origin: subscapular fossa

Insertion: lesser tubercle of humerus

Innervation: upper and lower subscapular nerves (C5, C6)

Action: Medially rotates and adduct arm- rotator cuff

Question 15

Latissimus Dorsi

Answer 15

Origin: spinous process of T7-L1 thoracolumbar
fascia, iliac crest, and inferior 3/4ribs

Insertion: intertubercular groove of humerus and inferior angle of the scapula

Innervation: thoracodorsal nerve (C6-C8)

Action: adducts, extend, and medially rotates humerus