Upper Limb 1 Station 3 - Pectoral Girdle, Scapular Movements and Muscles

Question 1

What is the pectoral/shoulder girdle?

Answer 1

The set of bones which connects the upper limb to the axial skeleton on each side

Question 2

What bones are in the pectoral girdle?

Answer 2

Clavicle

Scapula

Question 3

What is the joint called where the scapula and the clavicle meet?

Answer 3

Acromioclavicular joint

Question 4

Where on the scapula does the clavicle join?

Answer 4

Acromion process

Question 5

The entire upper limb and girdle articulate at one small joint only - what one is it?

Answer 5

Sternoclavicular joint

Question 6

How do you tell if the clavicle is in the correct plane/direction?

Answer 6

The medial end should stick out anteriorly more

Medial part that articulates with the sternum is larger than the one that joins onto the acromion

Question 7

Where is the conoid tubercle?

Answer 7

Inferior surface nearer lateral end

Question 8

Function of conoid tubercle?

Answer 8

Attachment point for the conoid ligament which binds the clavicle to the coracoid process of the scapula

Question 9

What part of clavicle is weakest?

Answer 9

Junction of middle and lateral thirds

Question 10

What type of joints are the acromioclavicular and sternoclavicular joints?

Answer 10

AC - synovial plane

SC - synovial saddle

Question 11

What muscles work to elevate the scapula?

Answer 11

Levator scapulae
Upper trapezius
Rhomboids

Question 12

What muscles depress the scapula?

Answer 12

Lower trapezius

Pectoralis major and minor

Question 13

What muscles protract (forwards movement) the scapula?

Answer 13

Serratus anterior

Pectoralis major and minor

Question 14

What muscles retract (backwards movement) the scapula?

Answer 14

Middle fibres of trapezius

Rhomboids

Question 15

What muscles retract (backwards movement) the scapula?

Answer 15

Middle fibres of trapezius

Rhomboids

Question 16

What muscles laterally (up) rotate the scapula? Therefore elevating the glenoid cavity.

Answer 16

Trapezius

Question 17

What muscles medially (down) rotate the scapula? Therefore depressing the glenoid cavity.

Answer 17

Levator scapulae
Rhomboids
Pec Major
(Gravity also)

Question 18

What is the scapulo-humeral rhythm?

Answer 18

For abduction of the arm, beyond the first 30 degrees (where all movement is done at the shoulder joint)
- for every 3 degrees of abduction, 2 occurs at the shoulder joint and 1 occurs at the scapula-thoracic joint.

Question 19

What is the scapulothoracic joint?

Answer 19

The movement of the scapula on the thoracic wall - not actually a joint