1. The document describes the muscles of the shoulder and pectoral region including their origin, insertion, nerve supply and action. 2. Key muscles discussed are the pectoralis major and minor, serratus anterior, subclavius, supraspinatus, infraspinatus, subscapularis, teres minor and major. 3. These muscles function in movements like abduction, adduction, medial and lateral rotation of the arm and stabilization of the shoulder joint.

1. Shoulder and Pectoral region

3. Transverse ligament
Long head of biceps

4. Coracoacromion
ligament
Trapezoid
part
Parts of
coracoclavicular
ligament
Conoid part

5. Acromioclavicular
ligament

6. A: pectoral major
B: supscapular muscle
C: latissmus dorsi

7. A: nerve to lattismus dorsi
(Thoracodorsal nerve)

9. A : teres major
B: teres minor
C: infraspinatus muscle
D: lattismus dorsi
E: deltoid muscle
F: trapizeus muscle
G: long head of triceps

10. Trapizeus
• Origin: occipital
• Insertion: has three parts: (‫ال‬ ‫عكس‬Origin of deltoid)
1- In posterior surface of the lateral third of clavicle
2- upper lip of the supine of scapula
3- site of acromioclavicular joint
• Nerve supply: Spinal part of accessory nerve (XI cranial nerve)
• Action: Abduction over 90 degree (hands above head)

11. Latissimus dorsi
• Origin: Lumber + Supine to iliac crest
• Insertion: Between the two lips of bicipital groove
• Nerve: thoracodorsal nerve
• Action: Adduction , medial rotation of the arm

12. Lavatory scapula, Rhomboid minor and Rhomboid
major
• Origin: Medial boarder of scapula posteriorly
• Nerve supply ! dorsal scapular nerve

13. Superficial Muscles of the Back

14. ‫في‬ ‫انذكرت‬ ‫نها‬/ ‫كتبتها‬ ‫لكن‬ ‫الظهر‬ ‫ت‬5‫عض‬ ‫تبع‬ ‫قبل‬ ‫ذكرتها‬ ‫الي‬ ‫ت‬5‫العض‬ ‫كل‬ ‫طبعا‬
:( ‫الشرح‬
***‫نهائيا‬ ‫ماانشرح‬ ‫انه‬ ‫يعني‬ ‫ماكتبته‬ ‫شي‬ ‫او‬ ‫معلومة‬ ‫أي‬ ****
‫اﻟﻠﻪ‬ ‫واﻟﻠﻪ‬

15. Pectoralis major
Origin:2 heads
• Clavicular head:
• Medial ½ of the front of the clavicle.
• Sternocostal head:
• Sternum.
• Upper 6 costal cartilages.
Insertion:
• Lateral lip of bicipital groove
Nerve Supply
• Medial & lateral pectoral nerves.
Action
• Adduction,
• medial rotation and
• flexion of the arm

16. Pectoralis minor
Origin
• 3rd, 4 th , & 5th ribs close to their
costal cartilages.
Insertion
• Coracoid process (scapula)
Nerve Supply
• Medial pectoral nerve.
Action
• Depression of the scapula.
• Draw the ribs upward and outwards
during deep inspiration

17. Serratus anterior
Origin
• Upper 8 ribs
Insertion
• anterior aspect of the medial border and inferior angle of scapula
Nerve Supply
• Long thoracic nerve (nerve to serratus anterior)
Action
• protrusion or protraction of the scapula
• Rotates scapula outwards in abduction arm above 90 degree

18. Subclavius
Origin
• Costochondral junction of the 1st rib.
Insertion
• Inferior surface of middle 1/3 of the clavicle
(Subclavian groove).
Nerve Supply
• Nerve to subclavius.
Action
• Fixes the clavicle during movement of shoulder
joint (pulls the clavicle medially to stabilize
sternoclavicular joint).

19. Supraspinatus muscle
Origin
• Medial 2/3 of Supraspinous fossa of
scapula.
Insertion
• Greater tuberosity of humerus
Nerve supply
• Suprascapular nerve
Action
• Abducts arm (0-15 degrees)

20. Infraspinatus muscle
Origin
• Medial 2/3 Infraspinous fossa of scapula
Insertion
• Greater tuberosity of humerus; capsule of
shoulder joint
Nerve supply
• Suprascapular nerve
Action
• Laterally rotates arm and stabilizes shoulder
joint

21. Subscapularis muscle
Origin
• Medial 2/3 subscapular fossa
Insertion
• Lesser tubercle of humerus
Nerve supply
• Upper and lower subscapular nerves
Action
• Medially rotates arm and stabilizes shoulder
joint

22. Teres minor
Origin
• Upper two thirds of lateral border of scapula
Insertion
• Greater tuberosity of humerus
Nerve supply
• Axillary nerve
Action
• Laterally rotates arm and stabilizes shoulder
joint
❑ All these 4 muscles belong to rotatory cuff
muscles

23. Teres major
Origin
• Lower third of lateral border of scapula
Insertion
• Medial lip of bicipital groove of humerus
Nerve supply
• Lower subscapular nerve
Action
• Medially rotates and adducts arm and stabilizes
shoulder joint