Shoulder muscles

Question 1

Serratus Anterior

Answer 1

O: surface of upper 8-9 ribs
I: medial border of scapula
N: Long Thoracic N. (C5, C6, C7)
F: ABD/ upward rotation of scapula, stabilizes medial border of scapula

Question 2

Rhomboid Major

Answer 2

O: spinous process of vertebrae TII - TV
I: medial border of scapula (from spine to inferior angle)
N: Dorsal Scapular N. (C4, C5)
F: ADD/ Elevates scapula

Question 3

Rhomboid Minor

Answer 3

O: Spinous processes of vertebrae CVII & TI
I: medial border of scapula (at the root of the scapular spine)
N: Dorsal Scapular N. (C4, C5)
F: ADD/ Elevates Scapula

Question 4

Latissimus Dorsi

Answer 4

O:
1. spinous processes of T7-T12 vertebrae
2. thoracolumbar fascia of spinous processes of lumbar vertebrae
3. related interspinous ligaments
4. iliac crest
5. lower 3-4 ribs
I: Floor of intertubercular sulcus of humerus
N: Thoracodorsal N. (C6, C8)
F: ADD/ IR/ Extension of shoulder at humerus

Question 5

Deltoid

Answer 5

O: 
- lateral 1/3 of clavicle
- acromion
- scapular spine
I: Deltoid tuberosity of humerus
N: Axillary N (C5, C6)
F: 
- Both: shoulder ABD
- Anterior: shoulder flexion/ IR
- Posterior: shoulder extension/ ER

Question 6

Supraspinatus

Answer 6

O: Supraspinous fossa of scapula
I: superior facet on greater tubercle of humerus
N: Suprascapular N (C5, C6)
F: *Rotator cuff muscle; initiation of ABD of arm to 15 degrees at Glenohumeral joint

Question 7

Infraspinatus

Answer 7

O: infraspinous fossa of the scapula
I: middle facet on posterior surface of greater tubercle of humerus
N: Suprascapular N (C5, C6)
F: *Rotator cuff muscle; ER of arm at Glenohumeral joint

Question 8

Teres Minor

Answer 8

O: lateral border of scapula
I: inferior facet of greater tubercle of humerus
N: axillary N (C5, C6)
F: *rotator cuff muscle; ER of arm at glenohumeral joint

Question 9

Subscapularis

Answer 9

O: subscapular fossa
I: lesser tubercle of humerus
N: upper and lower subscapular N’s (C5, C6, C7)
F: *rotator cuff muscle; IR of arm at glenohumeral joint

Question 10

Teres Major

Answer 10

O: inferior angle of scapula
I: crest of lesser tubercle of humerus
N: lower scapular N (C5, C6, C7)
F: IR/ extension of arm at GH joint

Question 11

Biceps Brachii

Answer 11

O: 
- long head: supraglenoid tubercle of scapula
- short head: apex of coracoid process
I: tuberosity of radius
N: musculocutaneous N (C5, C6)
F: 
- Elbow flexion/ supination
- assists in shoulder flexion

Question 12

Corachobrachialis

Answer 12

O: apex of coracoid process of scapula 
I: midshaft of humerus
N: Musculocutaneous N (C5, C6, C7)
F: 
- arm flexor at GH joint
- arm ADD

Question 13

Brachialis

Answer 13

O: anterior humerus and adjacent intermuscular septae
I: tuberosity of ulna
N: musculocutaneous N (C5-6), small contribution of radial N (C7)
F: elbow flexion

Question 14

Triceps brachii

Answer 14

O:
- long head: infraglenoid tubercle of scapula
- medial and lateral heads: posterior surface of humerus
I: olecranon of ulna
N: radial N (C6, C7, C8)
F:
- elbow extension
- long head: ADD/extension of arm at shoulder joint