Muscles Of The Shoulder And Arm

Question 1

Rotator cuff (sits)

Answer 1

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

Question 2

Supraspinatus OIAI

Answer 2

Origin:
- Supraspinous fossa

Insertion:
- superior aspect of the greater tubercle of the humerus

Actions:
- abduction of arm at glenohumeral joint

Innervation: suprascapular nerve

Question 3

Infraspinatus OIAI

Answer 3

Origin:
- infraspinous fossa
Insertion:
- posterior aspect of the greater tubercle of humerus

Actions:
- external rotation of arm at shoulder

Innervation:
- suprascapular nerve

Question 4

Teres Minor OIAI

Answer 4

Origin: Lateral border of scapula

Insertion: Posterior aspect of the greater tubercle of humerus

Actions: External rotation of arm at shoulder

Innervation: axillary nerve

Question 5

Subscapularis OIAI

Answer 5

Origin: Subscapular fossa

Insertion: Lesser tubercle of humerus

Actions: internal rotation of arm at shoulder

Innervation: Subscapular nerve

Question 6

Muscles that move the arm (non-rotator cuff, 7)

Answer 6

1. Deltoid
2. Coracobrachialis
3. Pectoralis major
4. Biceps brachii
5. Triceps brachii
6. Latissimus dorse
7. Teres major

Question 7

Deltoid OIAI

Answer 7

Origin:
1. Lateral clavicle
2. Acromion
3. Spine of scapula

Insertion: Deltoid tuberosity of the humerus

Actions:
1. All fibers: Abduction of arm
2. Anterior fibers: Medial rotation & Flexion of arm
3. Posterior fibers: Lateral rotation & extension of arm

Innervation: Axillary nerve

Question 8

Biceps Brachii OIAI

Answer 8

Origin:
- Long head: supraglenoid tubercle
- Short head: coracoid process

Insertion: radial tuberosity

Actions:
- Flexion of arm at glenohumeral joint
- Flexion of forearm at the elbow

Innervation: musculocutaneous nerve

Question 9

Coracobrachialis OIAI

Answer 9

Origin: Coracoid process of scapula

Insertion: Medial shaft of humerus

Actions:
- Adduction of arm at glenohumeral joint
- Flexion of arm at glenohumeral joint

Innervation: musculocutaneous nerve

Question 9

Triceps Brachii OIAI

Answer 9

Origin:
- Long head: infraglenoid tubercle
- Lateral head: posterior humerus
- Medial head: posterior humerus

Insertion: olecranon of ulna

Actions:
- Extension and adduction of arm
- Extension of forearm

Innervation: radial nerve

Question 10

Muscles of the arm that move the forearm (4)

Answer 10

1. Biceps brachii
2. Brachialis
3. Brachioradialis
4. Triceps brachii

Question 11

Superficial arm muscles

Answer 11

Biceps & Triceps

Question 12

Deep arm muscles

Answer 12

Coracobrachialis & Brachialis

Question 13

Brachioradialis OIAI

Answer 13

Origin:
- Lateral supracondylar ridge of the humerus

Insertion:
- Styloid process of radius

Actions:
- Flexion of the forearm at the elbow

Innervation:
Radial nerve