1.4.5. Extrinsic Muscles of the Shoulder

Question 1

What is the Definition of “Extrinsic Muscles of the Shoulder”?

Answer 1

Muscles which Originate from the Torso and Attach to the Bones of the Shoulder

Question 2

What are the 3 Bones of the Shoulder?

Answer 2

1. Clavicle
2. Scapular
3. Humerus

Question 3

What are the “Extrinsic Muscles of the Shoulder” also known as?

Answer 3

Superficial Back Muscles

Question 4

How many layers are the Extrinsic Muscles of the Shoulder are there?

Answer 4

2

Question 5

What are the 2 Layers of the Extrinsic Muscles of the Shoulder?

Answer 5

1. Superficial

2. Deep

Question 6

What are the 2 Superficial Extrinsic Muscles of the Shoulder?

Answer 6

1. Trapezius

2. Latissimus Dorsi

Question 7

How is the Trapezius described?

Answer 7

1. A Broad, Flat, Triangular Muscle - The muscles on each side forming a Trapezoid Shape
2. The most Superficial of all the Back Muscles

Question 8

Where does the Trapezius attach onto the Torso?

Answer 8

1. Base of the Skull (Where this Originates from)
2. Nuchal Ligament
3. Spinous Processes of C7 to T12

Question 9

Where does the Trapezius attach onto the Shoulder Bones?

Answer 9

1. Clavicle
2. Acromion
3. Spine of the Scapula

Question 10

What is the Motor Innervation of the Trapezius?

Answer 10

Accessory Nerve (Cranial Nerve XI)

Question 11

What provides the Proprioception Fibres to the Trapezius?

Answer 11

C3 and C4 Spinal Nerves

Question 12

What are the 3 Divisions (Bands) of the Trapezius?

Answer 12

1. Upper (Superior)
2. Middle
3. Lower (Inferior)

Question 13

What is the function of the Upper (Superior) Fibres of the Trapezius?

Answer 13

1. Elevation of the Scapula

2. Rotation of the Scapula during Abduction of the Arm

Question 14

What is the function of the Middle Fibres of the Trapezius?

Answer 14

Retraction of the Scapula

Question 15

What is the function of the Lower (Inferior) Fibres of the Trapezius?

Answer 15

Pull the Scapula Inferiorly

Question 16

How is the Latissimus Dorsi described?

Answer 16

Originating from the Lower Back and Covering a Large Area

Question 17

Where does the Latissimus Dorsi attach onto the Torso?

Answer 17

1. Spinous Processes of T6 to T12
2. Iliac Crest
3. Thoracolumbar Fascia
4. Inferior 3 Ribs (10, 11, 12)

Question 18

1. Where does the Latissimus Dorsi attach onto the Shoulder Bones?
2. What happens to the Fibres as they attach onto the Shoulder Bones?

Answer 18

1. Intertubercular Sulcus of the Humerus

2. The Fibres converge into a Tendon

Question 19

What is the innervation of the Latissimus Dorsi?

Answer 19

Thoracodorsal Nerve

Question 20

What is the function of the Latissimus Dorsi?

Answer 20

1. Extension of Upper Limb
2. Adduction of the Upper Limb
3. Medial Rotation of the Upper Limb

Question 21

Where are the Deep Extrinsic Muscles of the Shoulder Located?

Answer 21

1. In the Upper Back

2. Deep to the Trapezius

Question 22

What are the 3 Deep Extrinsic Muscles of the Shoulder?

Answer 22

1. Levator Scapulae
2. Rhomboid Major
3. Rhomboid Minor

Question 23

How is the Levator Scapulae described?

Answer 23

A Small, Strap-Like Muscle beginning in the Neck and Descending to Attach to the Scapula

Question 24

Where does the Levator Scapulae attach onto the Torso?

Answer 24

The Transverse Processes of C1 to C4

Question 25

Where does the Levator Scapulae attach onto the Shoulder Bones?

Answer 25

The Medial Border of the Scapula

Question 26

What is the innervation of the Levator Scapulae?

Answer 26

The Dorsal Scapula Nerve

Question 27

What is the function of the Levator Scapulae?

Answer 27

Elevate the Scapula

Question 28

Which, of Rhombod Major and Rhomboid Minor, is situated Superiorly?

Answer 28

Rhomboid Minor

Question 29

Where does the Rhomboid Major attach onto the Torso?

Answer 29

Spinous Processes of T2 to T5

Question 30

Where does the Rhomboid Major attach onto the Shoulder Bones?

Answer 30

Medial Border of the Scapula, between the:

1. Spine of the Scapula
2. Inferior Angle of the Scapula

Question 31

What is the innervation of the Rhomboid Major?

Answer 31

Dorsal Scapular Nerve

Question 32

What are the functions of the Rhomboid Major?

Answer 32

1. Retracts the Scapula

2. Rotates the Scapula

Question 33

Where does the Rhomboid Minor attach onto the Torso?

Answer 33

Spinous Processes of C7 to T1

Question 34

Where does the Rhomboid Minor attach onto the Shoulder Bones?

Answer 34

Medial Border of the Scapula, at the Level of the Spine of the Scapula

Question 35

What is the innervation of the Rhomboid Major?

Answer 35

Dorsal Scapular Nerve

Question 36

What is the function of the Rhomboid Major?

Answer 36

1. Retracts the Scapula

2. Rotates the Scapula