Myology of the Scapular Muscles

Question 1

What are the scapular muscles? (6)

Answer 1

1. Deltoids
2. Supraspinatus
3. Infraspinatus
4. Teres Minor
5. Subscapularis
6. Teres Major

Question 2

What are the heads of the deltoids?

Answer 2

Anterior, Middle, Posterior Heads

Question 3

Attachments of the deltoids

Answer 3

Medial Attach. (Anterior) : anterior lateral 1/3 of the clavicle
Medial Attach. (Middle): Lateral Acromion
Medial Attach. (Posterior): Spine of the scapula

Lateral Attach. (all): Deltoid tuberosity

Question 4

Action of the Deltoids

Answer 4

(All) : G-H Abduction
(Anterior) : Medial Rotation, Flexion, Horizontal Adduction
(Posterior) : Lateral Rotation, Extension, Horizontal Abduction

Question 5

The divergence of the pectoralis major and the anterior deltoid form a triangle with the clavicle.

Answer 5

Deltopectoral Triangle (A.k.a groove)

Question 6

Clinical Relevance of the Deltopectoral Triangle

Answer 6

Cephalic Vein lies within and is easiest access point when palpating the coracoid process

Question 7

What consists of the Rotator Cuff muscles?

Answer 7

1. Supraspinatus
2. Infraspinatus
3. Teres Minor
4. Subscapularis

Question 8

A.k.a for Rotator Cuff muscles

Answer 8

SItS

Question 9

What do the Rotator Cuff muscles do?

Answer 9

• Support/stabilize the G-H joint

- Helps control movement

Question 10

Supraspinatus Attachments

Answer 10

Medial: Supraspinous Fossa
Lateral: Superior facet of the greater tubercle of the humerus (also the G-H joint capsule)

Question 11

Supraspinatus Actions

Answer 11

• Abduction

- Stabilizes the G-H joint by ‘tucking’ the head of the humerus up into the glenoid fossa

Question 12

Infraspinatus Attachment

Answer 12

Medial: Infraspinous fossa
Lateral: Middle facet of the greater tubercle of the humerus (also G-H capsule)

Question 13

Infraspinatus Actions

Answer 13

G-H external rotation

Question 14

Teres Minor Attachments

Answer 14

Medial: Lateral middle border of the scapula (b/w triceps and teres major)
Lateral: Inferior facet of the greater tubercle of the humerous (also G-H capsule)

Question 15

Teres Minor Actions

Answer 15

G-H external rotation

Question 16

Subscapularis Attachment

Answer 16

Medial: Subscapular fossa
Lateral: Lesser tubercle (medial lip of the bicipital groove) of the humerus (also G-H capsule)

Question 17

Teres Major Attachment

Answer 17

Medial: Posterior surface of the inferior angle of the scapula
Lateral: Medial lip of the bicipital groove

Question 18

Teres Major Actions

Answer 18

• G-H internal rotation
• G-H extension
• G-H adduction

Question 19

Which two muscles have the same actions?

Answer 19

Latissimus Dorsi and Teres Major