WINDSOR UNIVERSITY SCHOOL OF MEDICINE St.Kitts

1. Dr. SREEKANTH THOTA DEPARTMENT OF ANATOMY UPPER LIMB WINDSOR UNIVERSITYSCHOOL OF MEDICINESt.Kitts SHOULDER

2. SHOULDER • The shoulder is the region of upper limb attachment to the trunk and neck.

3. Bones of the Shoulder Girdle • Clavicle and scapula, which form the pectoral girdle (shoulder girdle) • The proximal end of the humerus.

4. Muscles Shoulder Region

5. Anterior Axioappendicular Muscles of the Upper Limb • PECTORALIS MAJOR • PECOTORALIS MINOR • SUBCLAVIUS • SERRATUS ANTERIOR

6. PECTORALIS MAJOR • Origin: Clavicle, sternum, and upper six costal cartilages • Insertion : Lateral lip of bicipital groove of humerus • N. supply: Medial and lateral pectoral nerves • Action: Adducts arm and rotates it medially; clavicular fibers also flex arm

7. PECTORALIS MAJOR

8. PECOTORALIS MINOR • Origin: Third, fourth, and fifth ribs • Insertion : Coracoid process of scapula • N. supply: Medial pectoral nerve • Action: Stabilizes scapula by drawing it inferiorly

9. SUBCLAVIUS • Origin: First costal cartilage • Insertion : Clavicle • N. supply: Nerve to subclavius • Action: Depresses the clavicle

10. SERRATUS ANTERIOR • Origin: Upper eight ribs • Insertion :Anterior surface of medial border of scapula • N. supply: Long thoracic nerve • Action: Protracts scapula and rotates scapula

11. Paralysis of the Serratus Anterior(winged scapula ) Due to loss of Innervation-long thoracic nerve • When the serratus anterior is paralyzed owing to injury to the long thoracic nerve, the medial border of the scapula moves laterally and posteriorly away from the thoracic wall, giving the scapula the appearance of a wing.

12. Posterior Axioappendicular Muscles • The posterior axioappendicular muscles attach the superior appendicular skeleton (of the upper limb) to the axial skeleton (in the trunk). • 1.Trapezius • 2.Latissimus dorsi • 3. Rhomboid major and minor • 4. Levator scapulae

13. Trapezius • Origin: Occipital bone, ligamentumnuchae, spine of seventh cervical vertebra, spines of all thoracic vertebrae • Insertion : Upper fibers into lateral third of clavicle; middle and lower fibers into acromion and spine of scapula • N. supply: Spinal part of accessory nerve (motor) • Action: Upper fibers elevate the scapula; middle fibers pull scapula medially; lower fibers pull medial border of scapula downward

15. Injury of the Accessory Nerve (CN XI) • The primary clinical manifestation of accessory nerve palsy is a marked ipsilateral weakness when the shoulders are elevated (shrugged) against resistance.

16. Latissimusdorsi • Origin: Iliac crest, lumbar fascia, spines of lower six thoracic vertebrae, lower three or four ribs, and inferior angle of scapula • Insertion: Floor of bicipital groove of humerus • N. supply:Thoracodorsal nerve

17. Latissimusdorsi Action: Extends, adducts, and medially rotates the arm

18. Injury of the Thoracodorsal Nerve • Surgery in the inferior part of the axilla puts the thoracodorsal nerve supplying the latissimusdorsi at risk of injury. • With paralysis of the latissimusdorsi, the person is unable to raise the trunk with the upper limbs, as occurs during climbing.

19. Levator Scapulae • Origin: Transverse processes of first four cervical vertebrae • Insertion: Medial border of scapula • N. supply:dorsal scapular nerve • Action:Elevates scapula

20. Rhomboids minor and major • N. supply: Dorsal scapular nerve • Action: Retracts scapula

21. Scapulohumeral Muscles • Scapulohumeral muscles: • The six scapulohumeral muscles are relatively short muscles that pass from the scapula to the humerus and act on the glenohumeral joint. • 1.Deltoid • 2.Teres major • 3.Teres minor • 4.Supraspinatus • 5.Infraspinatus • 6.Subscapularis

22. Deltoid • Origin: Lateral third of clavicle, acromion, spine of scapula • Insertion: Middle of lateral surface of shaft of humerus • N. supply: Axillary nerve

23. Deltoid Action: Anterior part: flexes and medially rotates armMiddle part: abducts armPosterior part: extends and laterally rotates arm

24. Testing deltoid muscle • The examiner resists the patient's abduction of the limb by the deltoid. • If the deltoid is acting normally, contraction of the middle part of the muscle can be palpated.

25. Injury to the Axillary Nerve The deltoid is a common site for the intramuscular injection of drugs. The axillary nerve runs transversely under cover of the deltoid at the level of the surgical neck of the humerus. The deltoid atrophies when the axillary nerve (C5 and C6) is severely damaged.

26. Deltoid atrophy

27. Teres Major • Origin: Lower third of lateral border of scapula • Insertion:Medial lip of bicipital groove of humerus • N. supply:Lowersubscapular nerve • Action:Adducts and medially rotates arm

29. Rotator Cuff Muscles • Four of the scapulohumeral muscles supraspinatus, infraspinatus, teres minor, and subscapularis(referred to as the SITS muscles) are called rotator cuff muscles because they form a musculotendinous rotator cuff around the glenohumeral joint.

30. Teres minor • Origin: Middle part of lateral border of scapula • Insertion: Inferior facet of greater tubercle of humerus • N. supply:Axillary nerve • Action:Laterally rotates arm and stabilizes shoulder joint

31. Supraspinatus • Origin:Supraspinousfossa of scapula • Insertion: Superior facet of greater tubercle of humerus • N. supply:Suprascapular nerve • Action: Initiates and assists deltoid in abduction of arm and acts with rotator cuff muscles.

32. Infraspinatus • Origin:Infraspinousfossa of scapula • Insertion: Middle facet of greater tubercle of humerus • N. supply: Suprascapular nerve • Action: Laterally rotates arm and stabilizes shoulder joint

33. Subscapularis • Origin:Subscapularfossa (most of anterior surface of scapula) • Insertion: Lesser tubercle of humerus • N. supply: Upper and lower subscapular nerves • Action: Medially rotates and adduct arm

34. Rotator Cuff Injuries and the Supraspinatus • Trauma may tear or rupture one or more of the tendons of the SITS muscles; that of the supraspinatus is most commonly involved.

35. Rotator Cuff Injuries

36. Triangle of Auscultation • Medial Border: • Trapezius muscle • Lateral Border: • scapula • Inferior Border (base): • LatissimusDorsi • It is an area of little muscle and hence a good place to listen to the posterior segment of the lungs

37. Gateways to the posterior scapular region

38. Arteries and nerves associated with gateways in the posterior scapular region

39. QUADRANGULAR SPACE: • Superior border: • Teres Minor • Inferior border: • Teres Major • Lateral border: • Surgical neck of the humerus • Medial border: • Long Head of Triceps

40. CONTENTS • 1- Axillary Nerve • 2- Posterir Circumflex Humeral Artery

41. Quadrilateral Space Syndrome • Quadrilateral space syndrome usually happens from overuse, especially with overhead sports like throwing and swimming. The syndrome can also be caused by an injury, like a shoulder dislocation.

42. TRIANGULAR [upper] space • LATERAL BORDER: • Long Head of the Triceps • Upper border: • Teres Minor and subscapularis • Lower border: • Teres Major • CONTENTS • Circumflex Scapular Branch • of the Subscapular artery

43. Lower Triangular Space • Medially • long head of the triceps brachii • Latteraly • shaft of the humerus • Superiorly • teres major

44. Contents • 1-Radial nerve • 2-Profunda brachii artery