Muscles

Question 1

What are the Superficial Extrinsic Shoulder Muscles and the Deep Extrinsic Shoulder Muscles?

Answer 1

Superficial:
Trapezius
Latissimus Dorsi
Deep:
Levator Scapulae
Rhomboids

Question 2

What are the Scapulohumeral Muscles?

Answer 2

Deltoid, Teres Major

Question 3

What are the rotator cuff muscles?

Answer 3

Supraspinatous
Infraspinatus
Teres Minor
Subscapularis

Question 4

What are the Trapezius attachments?

Answer 4

Origin - Axial Skeleton (Skull down to T12)

Attachments - Posterior surface of scapula and clavicle

Question 5

What is the Trapezius Innervated by?

Answer 5

Accessory Nerve (C3 and C4)

Question 6

Trapezius actions

Answer 6

Upper fibres rotate and elevate scapula
Middle fibres retract scapula
Lower fibres pull scapula inferiorly

Question 7

How can you test the accessory nerve?

Answer 7

Elevate shoulder against resistance

Question 8

Latissimus Dorsi attachments

Answer 8

Originates thoracic spine, iliac crest and the inferior 3 ribs.
Attaches to intertubecular groove of humerus

Question 9

Latissimus Dorsi innervation

Answer 9

Thoracodorsal nerve

Question 10

Latissimus Dorsi actions

Answer 10

Extension of the arm at the shoulder
Adduction at the shoulder
Medial rotation of the arm

Question 11

Levator Scapulae attachments

Answer 11

Transverse processes of C1-C4 vertebrae

Attaches to the medial border of the scapula, superior to spine

Question 12

Levator Scapulae innervation

Answer 12

Dorsal scapular nerve

Question 13

Levator Scapulae actions

Answer 13

Elevates scapula

Rotates scapula to tilt glenohumeral joint inferiorly

Question 14

Rhomboid attachments

Answer 14

Minor: C7-T1 vertebrae
Major: T2-T5 vertebrae
Attach medial border of scapula

Question 15

Rhomboid innervation

Answer 15

Dorsal scapula nerve

Question 16

Rhomboid Actions

Answer 16

Retracts scapula
Rotates scapula to tilt glenohumeral joint inferiorly
Can also fix the scapula to the thoracic wall

Question 17

Deltoid attachments

Answer 17

Originates: Scapula and Clavicle
Attachments: Deltoid tuberosity on the lateral surface of the humerus

Question 18

Deltoid Innervation

Answer 18

Axillary nerve

Question 19

Deltoid Actions

Answer 19

Anterior: flex the arm at the shoulder
Posterior: extend the arm at the shoulder
Middle: major abductor of the arm 15-90

Question 20

Teres Major attachment

Answer 20

Originate: the inferior angle of the scapula on the posterior side
Attachment: intertubecular groove of the humerus

Question 21

Teres Major innervation

Answer 21

lower subscapular nerve

Question 22

Teres Major actions

Answer 22

Adducts at the shoulder

medially rotates the arm

Question 23

Supraspinatus attachments

Answer 23

Originates from the supraspinous fossa on the posterior surface of the scapula
Attachment: greater tuberosity of the humerus

Question 24

Supraspinatus innervation

Answer 24

suprascapular nerve

Question 25

Supraspinatous Actions

Answer 25

First 15 degrees of arm adduction

Question 26

Infraspinatous attachments

Answer 26

Origin: infraspinous fossa
Attaches: greater tubercle of the humerus

Question 27

Infraspinatous innervation

Answer 27

Innervated by the suprascapular nerve

Question 28

Infraspinatous action

Answer 28

Lateral rotation of the arm

Question 29

Subscapularis attachments

Answer 29

Origin: Subscapularis fossa, costal surface of scapular
Attaches: lesser tubercle of humerus

Question 30

Subscapularis innervation

Answer 30

Upper and lower subscapular nerves

Question 31

Subscapularis actions

Answer 31

Medial rotates the arm

Question 32

Teres Minor attachments

Answer 32

Origin: midway down the medial border
Attaches: greater tubercle of the humerus

Question 33

Teres Minor innervation

Answer 33

Axillary nerve

Question 34

Teres Minor actions

Answer 34

Lateral rotation of arm