Shoulder girdle muscles

Question 1

What do the shoulder girdle muscles do

Answer 1

All the shoulder girdle muscles have proximal attachments (origin) on the axial
skeleton, and distal attachments (insertion) on the shoulder girdle (scapula
and/or clavicle).
None of the muscles cross the glenohumeral joint, and thus none directly
cause GH joint motion.

Question 2

What are the shoulder girdle muscles

Answer 2

Two anterior (anterior trunk)
* Pectoralis minor
* Serratus anterior (anterior to the scapula)
Three posterior (Posterior trunk)
* Trapezius
* Rhomboids
* Levator scapulae

Question 3

Concentric actions of the pectoralis minor

Answer 3

Protraction, downward rotation and depression

Question 4

Concentric actions of the seratus anterior

Answer 4

Protraction and upward rotation

Question 5

Concentric actions of the trapezius

Answer 5

Upper fibres - elevation
Middle fibres - elevation, retraction, upwards rotation
Lower - depression, retraction and upwards rotation

Question 6

Concentric actions of the rhomboids

Answer 6

Elevation, retraction, downwards rotation

Question 7

Concentric action of the levator scapulae

Answer 7

Elevation