Back Muscles Insertion

Question 1

Pectoralis major

Answer 1

Originates from Clavicle and sternum from costal cartilage 1-6 and aponeurosis of external oblique. Inserts into Interubercular groove of humerus for arm extension.

Question 2

Latissimus dorsi

Answer 2

From T6-12 spinous process, lumbosacral fascia and iliac crest, It attaches to the Biccipital groove of the humerus for ** depression of scapula and adduction.**

It is innervated by the thoracodorsal nerve.

Question 3

Serratus anterior

Answer 3

Originates from the first 8 ribs and attaches to the medial border of the scapula.

**It protracts scapula and lift it forward.

Innervated by the long thoracic nerve.**

Question 4

Pectoralis minor

Answer 4

Originates from the costal cartilage 3-5 to insert into coracoid process of scapula.

Causes depression of scapula, innervated by medial pectoral nerve.

Question 5

Subclavius

Answer 5

Originates from the costachondral rib to insert to the subclavian groove of the clavicle for depressing the clavicle.

Innervated by the subclavius nerve on C5.

Question 6

Trapezius

Answer 6

External occipital protuberance to spinal process of T12 and spine of scapula to accordion.
** Elevating and retracting the scapula and adduction. It is innovated by the CN XI**

Question 7

Rhomboid major

Answer 7

Originates from T2-T5 to attach to medial border of scapula for adduction of scapula.
Innervated by the dorsal scapular nerve of C5.

Question 8

Rhomboid minor

Answer 8

Originates from C7-T1 to attach to medial border to scapula for scapula adduction. Innervated by the dorsal scapular nerve of C5.

Question 9

What is the attachment of the rhomboid muscles?

Answer 9

Medial border of scapula.

Question 10

Levator scapulae

Answer 10

Transverse process of C1 to C4 to the superior angle and medial border of scapula to elevate scapula.

Innervated by the dorsal scapular nerve of C5.

Question 11

Deltoid

Answer 11

3 sets of fibres depending on origin from anterior clavicle, lateral acromion and posterior spinal to attach to deltoid tuberosity on humerus.

Innervated by axillary nerve.

Question 12

Teres major

Answer 12

Originates from inferior scapula angle to attach to inter tubercular groove of humerus for
**adduction of arm. **

Innervated by the lower subcapsular nerve.

Question 13

Teres minor

Answer 13

Lateral border of scapula and inserts into the inferior aspect of the greater tuberosity of humerus.

Important for external rotation of the arm, Innervated by axillary nerve.

Question 14

Supraspinatous

Answer 14

Originates from supraspinatous fossa to the superior aspect of the greater tubercle of the humerus. Involved in abduction of arm.
-> Part of the rotator cuff muscles, innervated by the **supracapsular nerve. **

Question 15

Infraspinatous

Answer 15

Originates from the infraspinatous fossa to insert into the medial aspect of the greater tuberosity of the humerus.

For external rotation of arm and abduction. Innervated by supracapsular nerve from C5.

Question 16

Subscapularis

Answer 16

Subscapularis fossa to the lesser tuberosity of the humerus for ** internal rotation of arm.**

Innervated by the upper and lower subcapsular nerve on the posterior cord.

Question 17

Which rotator cuff muscles are responsible for external rotation?

Answer 17

Infraspinatous and teres minor.

Question 18

Biceps brachii

Answer 18

Two heads which insert onto the radial tuberosity, innervated by musculocutaneous nerve for elbow flexion.

It has an aponeurosis which attaches and forms the roof of the antecubital fossa.

Question 19

Where does the long head of biceps arise?

Answer 19

Supraglenoid tubercle which travels down the intertubercular groove of humerus

Question 20

Where does the short head of biceps arise?

Answer 20

Coracoid process of scapula along with coracobrachialis.

Question 21

Brachialis

Answer 21

Originates from inferior 1/3 of humerus and inserts into the ulnar tuberosity.

Innervated by musculocutaneous nerve.

Question 22

Coracobrachialis

Answer 22

From coracoid process and inserts into the medial surface of the humerus midshaft.

Innervated by the musculocutaenous nerve for FLEXION of SHOULDER.

Question 23

Triceps brachii

Answer 23

Three heads
Originate from infraglenoid tubercle, superior and inferior to humerus radial groove

They have a common attachment to the olecranon of ulna.

Question 24

Where does long head of triceps arise?

Answer 24

Infraglenoid tubercle

Question 25

Where does the medial head of triceps arise?

Answer 25

Posterior surface of humerace BELOW radial groove

Question 26

Where does the short head of triceps arise?

Answer 26

Posterior surface of humerus ABOVE to radial groove

Question 27

Order of elbow flexors from superficial to deep

Answer 27

Biceps brachii
Brachialis
Coracobrachialis

Question 28

Role of anterior belly of deltoid muscle

Answer 28

Clavicle to acromion for Flexion of humerus.

Question 29

Role of middle belly of deltoid muscle

Answer 29

Acromion to clavicle for Abduction of humerus.

Question 30

Role of posterior belly of deltoid muscle

Answer 30

Goes across the spine of scapula for Extension of humerus.

Question 31

Which nerve is located near the surgical neck of the humerus?

Answer 31

Axillary nerve

Question 32

Which nerve is located near the spiral groove of humerus?

Answer 32

Radial nerve

Question 33

Which nerve is located near the mid axillary line?

Answer 33

Long thoracic

Question 34

Which nerve is located near the medial epicondyle of the humerus?

Answer 34

Ulnar nerve

Question 35

Which nerve lies between the long and medial head of triceps?

Answer 35

Radial nerve.