Lecture 12: Pectoral Girdle

Question 1

What is the upper limb made up of?

Answer 1

arm, forearm, hand and shoulder (pectoral girdle)

Question 2

The shoulder joint has the ___ range of motion and is the ___ stable joint. This means it requires ____ of muscles.

Answer 2

widest; least; lots

Question 3

Whats the fancy word that refers to the arm?

Answer 3

brachium

Question 4

If you puff your chest out, what type of movement does that do to the pectoral girdle?

Answer 4

retraction

Question 5

If you pull your shoulder forward, what type of movement does the pectoral girdle do?

Answer 5

protraction

Question 6

If you shrug, your pectoral girdle is ___ and if you relax back down your pectoral girdle is ___

Answer 6

elavated: depressed

Question 7

If you raise your arm, you are ____ rotating your glenoid fossa of your scapula.

Answer 7

superiorly

Question 8

If you clap your hands behind you, you are ____ rotating your glenoid fossa of your scapula.

Answer 8

inferiorly

Question 9

What main bones makes up the pectoral girdle?

Answer 9

clavicle and scapula

Question 10

What are the main bone structures of the clavicle?

Answer 10

deltoid tubercle, costoclavicular roughened area (for ligament attachment), subclavian groove (for muscle attachment

Question 11

What are the 3 angles of the scapula?

Answer 11

superior angle, inferior angle, glenoid fossa

Question 12

What are the 3 borders of the scapula?

Answer 12

superior border, medial border, lateral border

Question 13

What are the 3 surfaces of the scapula?

Answer 13

subscapula fossa (anterior view), infraspinous fossa, supraspinous fossa (both posterior view)

Question 14

What are the 3 protuberene of the scapula?

Answer 14

coracoid (seen on anterior), acromion and spine (seen on posterior)

Question 15

What are the two main main joints of the pectoral girdle?

Answer 15

sternoclavicular joint

Acromioclavicular

Question 16

Describe the sternoclavicular joint

Answer 16

saddle shaped synovial joint that sits between the medial end of the clavicle and the manubrium (sternum)

Question 17

What are the four most important ligaments of the sternoclavicular joint?

Answer 17

Posterior and anterior sternoclavicular ligament

Interclavicular and consto-clavicular ligament (this is the strongest)

Question 18

Where is the acromioclavicular joint located?

Answer 18

between the lateral end of the clavicle and the medial end of the acromion

Question 19

what lies inside the acromioclavicular joint and what surrounds it?

Answer 19

intra-articular disc; acromio-clavicular ligament

Question 20

What two muscles help strengthen the AC joint?

Answer 20

Trapezius and deltoids

Question 21

What ligament strengthens the AC joint (and the acromioclavicular ligament)?

Answer 21

coraco-clavicular ligament

Question 22

What is the insertion and origin of the subclavius?

Answer 22

O= costal cartilage of the first rib 
I= clavicle

Question 23

What is the insertion and origin of the pectoralis minor?

Answer 23

O= 3rd, 4th and 5th rib
I= Coracoid process of the scapula

Question 24

Primary action of the subclavius?

Answer 24

“braces” the clavicle

Question 25

Primary action of the pectoralis minor?

Answer 25

depresses the scapula

Question 26

What is the insertion and origin of the serratus anterior ?

Answer 26

``` O= ribs 1- 8/9 I= medial border of the scapula ```

Question 27

Primary actions of the serratus anterior?

Answer 27

- protracts scapula | - lower fibres help superiorly rotate scapula

Question 28

What is the insertion and origin of the three regions of the trapezius?

Answer 28

Superior O= Skull to mid cervicle verterbrae I= clavicle Middle O=beginning of thoracic verterbrae to mid thoracic verterbrae I= acromion of scapula Inferior O= mid to end of thoracic vertebrae I= spine of the scapula

Question 29

Primary action of the traps

Answer 29

``` altogether= retracts scapula superior= elevate scapula mid= retract scapula inferior= depress scapula superior + inferior = superior rotation of scapula ```

Question 30

What is the insertion and origin of the levator scapulae

Answer 30

``` O= cervical vertebraes I= coracoid process of the scapula ```

Question 31

Primary action of the levator scapulae

Answer 31

elevate scapula

Question 32

What are the insertion and origin of the major and mino rhomboids?

Answer 32

``` O= beginning of the thoracic to mid thoracic I= medial border of the scapula ```

Question 33

Primary action of rhomboids

Answer 33

Retract scapula

Question 34

What is the insertion and origin of the pectoralis major?

Answer 34

``` O= clavicular head AND the sterno-costal head I= lateral lip of the inter-tubercular groove of humerus ```

Question 35

primary action of the pectoralis major

Answer 35

- adducts humerus - medially rotates humerus - assist in protraction of scapula (flys on cables)

Question 36

what is the insertion and origin of the latissimus dorsi?

Answer 36

``` O= lumbar verterbrae and iliac crest I= floor of inter-tubercular groove on the anterior surface of the humerus ```

Question 37

Primary action of latissium dorsi

Answer 37

- adducts the humerus (lat pulldowns) - medially rotates humerus - lower fibres help depress scapular by pulling on humerus

Question 38

What is the apopneurosis of the latissimus dorsi?

Answer 38

It is the flat tendon seen on your lower back