1.3.4. Scapular Movements and Muscles

Question 1

Where does the initial movement occur for the Abduction of the Arm (from the anatomical position)?

Answer 1

The Shoulder (Glenohumeral) Joint

Question 2

After the first 30 degrees abduction, what other joint becomes involved?

Answer 2

The Scapula-Thoracic Joint

Question 3

What is the Scapulo-Humeral Rhythm?

Answer 3

The 2:1 ration of:
2 degrees occurring at the Shoulder (Glenohumeral) Joint
1 degree occurring at the Scapulo-Thoracic joint

Question 4

What is the Scapulo-Thoracic Joint?

Answer 4

The movement of the Scapula on the Thoracic Wall

Question 5

Is the Scapulo-Thoracic Joint a True Joint?

Answer 5

No - movement occurs around a joint axis, but no joint surfaces or structures are present

Question 6

What muscles cause elevation of the Scapula?

Answer 6

1. Superior Fibres of the Trapezius Muscle
2. Levator Scapulae
3. Rhomboids

Question 7

What muscles cause depression of the Scapula?

Answer 7

1. Inferior Firbres of the Trapezius
2. Pectoralis Minor
3. Subclavious
4. Serratus Anterior
5. Latissimus Dorsi

Question 8

What muscles cause protraction (forward movement) of the Scapula?

Answer 8

1. Serratus Anterior
2. Pectoralis Major may assist
3. Pectoralis Minor may assist

Question 9

What muscles cause retraction (backward movement) of the Scapula?

Answer 9

1. Middle fibres of the Trapezius
2. Rhomboids

Question 10

What muscles cause lateral (upward) rotation of the Scapula? (Elevating the Glenoid Cavity)

Answer 10

1. Superior Fibres of the Trapezius
2. Serratus Anterior

Question 11

What muscles cause medial (downward) rotationof the Scapula? (Depressing the Glenoid Cavity)

Answer 11

1. Levator scapulae
2. Rhomboid
3. Pectoralis Major
   (Gravity will assist)