Upper Limb: Pectoral and Scapular Regions

Question 1

In the anterior pectoral region, name the muscle that moves the clavicle? and the nerve that innovates it

Answer 1

Subclavius - Nerve to subclavius (C5, 6)

Question 2

In the anterior pectoral region, name the muscle that moves the humerus? and the nerve that innovates it

Answer 2

Pectoralis Major - Innovated by the median (C8,T1) and the Lateral Pectoral nerve (C5,6,7)

Question 3

In the anterior pectoral region, what two muscles move the scapula? and the nerve that innovates it

Answer 3

Pectoralis minor - Medial Pectoral (C8 and T1)

Serratus anterior - Long thoracic nerve (C5,6,7)

Question 4

What are the main actions of the pectoralis major? and name its two heads

Answer 4

It adducts and medially rotates. Also is involved in flexion and extension.. Has a clavicular head and sternocostal head

Question 5

What are the main actions of the serratus anterior?

Answer 5

It protracts the scapula, prevents winging of the scapula and is involved in scapular rotation (holds the scapula against the body)

Question 6

What are the main actions of pectoralis minor? where does it attach?

Answer 6

It stabilises and depresses the scapula. Attaches from ribs 2/3/4 to the coracoid process

Question 7

What are the main actions of subclavius

Answer 7

Stabilises and depresses the clavicle

Question 8

Name the extrinsic back muscle that moves the humerus and what nerve is it supplied by

Answer 8

Latissimus Dorsi which is supplied the by thoracodorsal nerve (C6/7/8)

Question 9

Name the three extrinsic back muscles that move the scapula

Answer 9

Trapezius - spinal accessory nerve (cranial nerve)
Rhomboids (major and minor) - Dorsal scapular nerve (C4/C5)
Levator scapula - Cervical nerves (C3/4) and Dorsal Scapular

Question 10

Describe the action of latissimus dorsi at the GH joint

Answer 10

Extends, Adducts and medially rotates

Question 11

What main muscle and other synergists are involved in scapular elevation?

Answer 11

Upper Trapezius

lev scapula and rhomboids

Question 12

What main muscle and other synergists are involved in scapular depression

Answer 12

Not muscle but gravity, assisted by pectoralis maj +min, lat dorsi ect

Question 13

What main muscle and other synergists are involved in scapular protraction

Answer 13

Serratus anterior

pectoralis muscles

Question 14

What main muscle and other synergists are involved in scapular retraction

Answer 14

Middle trapezius

rhomboids

Question 15

What main muscle and other synergists are involved in scapular upward rotation

Answer 15

Upper trapezius and serratus anterior

lower trapezius

Question 16

What main muscle and other synergists are involved in scapular downward rotation

Answer 16

Latissimus Dorsi

lev scapula, rhomboids, pecs

Question 17

Name the intrinsic shoulder muscles from the scapula to the humerus that move the GH joint and the nerve that innervates them

Answer 17

Deltoid - Axillary Nerve (C5,6)
Teres Major - Lower subscapular nerve (C5,C6)
Rotator cuff - SITS

Question 18

Name the three functional parts of the deltoid and what action they preform

Answer 18

Anterior - Flexion and medial rotation
Middle - Abduction
Posterior - Extension and lateral Rotation

Question 19

What is the deltopectoral groove?

Answer 19

A groove between the deltoid and pectorarlis major where the cephalic vein lays.

Question 20

Where are the attachment sites for teres major?

Answer 20

The inferior angle of the scapula and the medial lip of the humerus.

Question 21

Name the four rotator cuff muscles and what nerve innervates them. Look at the location of the muscles.

Answer 21

SITS
Supraspinatus - Suprascapular nerve (C5,C6)
Infraspinatus - Suprascapular nerve (C5,C6)
Teres Minor - Axillary nerve (C5,C6)
Subscapularis - Upper and Lower subscapular nerves (C5/6/7)

Question 22

Describe the movements that each of the rotator cuff muscles help

Answer 22

Supraspinatus - initiates abduction (first 15 degrees)
Infraspinatus - External rotation
Teres Minor - External rotation
Subscapularis - internal rotation

Question 23

Where do the rotator cuff muscles insert on the humerus?

Answer 23

3 On the greater tubercle - Supraspinatus (runs underneath the acromion), Infraspinatus and teres minor
1 on the lesser tubercle - subscapularis

Question 24

Name the three arm muscles that cross the GH joint

Answer 24

Long head of biceps brachii
Coracobrachialis
Long head of tricep

Question 25

Name the fascia that goes around pectoralis Major and Minor and then also the fascia then extends down the arm

Answer 25

Major - Pectoral fascia, beneath this you will find the fascia for;
Minor - Clavipectoral fascia
Extending down the arm - brachial Fascia

Question 26

Describe the fascia of the supraspinatus and infraspinatus muscles

Answer 26

Each muscle has their own fascia that is very dense and is even the origin for some of the muscle fibres. If there is a break in the scapula blood can collect in this fascia giving a triangular bruise

Question 27

What is the axilla?

Answer 27

It is the pyramidal space inferior to the glenohumeral joint but superior to the axillary fascia

Question 28

Name the four walls of the axilla and what the wall is composed of and the base and apex

Answer 28

Anterior wall - Pectoralis major + pectoral fascia and pectoralis minor + clavipectoral fascia
Posterior wall - Scapula, subscapularis and inferiorly is teres major and lat. Dorsi
Medial Wall - Ribs 1-4 and serratus anterior
Lateral Wall - Humerus (intertubercle sulcus)
Floor of axillia - skin and axillary fascia.
Apex - cervico-axillary canal which boarders are the 1st rib, clavicle and scapule

Question 29

Describe what forms the anterior and posterior fold of the axilla

Answer 29

Anterior Fold - Pectoralis Major

Posterior fold - Teres Major and Lat.Dorsi

Question 30

What passes throught the axilla

Answer 30

Axillary vessels, brachial plexus (cords and branches) and axillary sheath

Question 31

Name the 5 lymphatic gorups of the axilla

Answer 31

Lateral (humeral), Posterior (subscapular), Anterior (pectoral) which all drain to central lymphnodes which then drain to apical lymph-nodes

Question 32

Name the three scapular spaces

Answer 32

Upper triangular (the triangular space)
Quadrangular
Lower triangular (triangular interval)

Question 33

Name the borders and contents of the quadrangular space

Answer 33

Boarders - Teres Minor, Teres Major, Humerus, Long head of triceps
Contents - Posterior circumflex artery, Axillary nerve and surgical neck of humerus

Question 34

Name the borders of the upper triangular space (the triangular space)

Answer 34

Boarders - Teres Major, Teres Minor and long head of triceps

Contents - Circumflex scapular artery

Question 35

Name the borders and contents of the triangular interval (lower triangular space)

Answer 35

Borders - Lateral head of triceps, Long head of triceps and Teres major
Contents - Radial nerve, Profunda brachii artery