Chapter 5: The Upper Extremity: The Shoulder Region

1. Chapter 5:The Upper Extremity:The Shoulder Region KINESIOLOGY Scientific Basis of Human Motion, 10th edition Luttgens & Hamilton Presentation Created by TK Koesterer, Ph.D., ATC Humboldt State University

2. Objectives 1. Name, locate, & describe the structure & ligamentous reinforcements of the joints 2. Name & demonstrate movements possible 3. Name & Locate muscles & muscle groups, and name their primary actions 4. Analyze the fundamental movements with respect to joint & muscle actions 5. Describe common athletic injuries

3. Acromioclavicular (AC) Joint • Articulation of acromion & distal end of clavicle • AC ligament strengthens superiorly • Aponeurosis of trapezius & deltoid strengthen posteriorly • Coracoclavicular ligament further stabilizes Fig 5.1

4. Sternoclavicular (SC) Joint • Proximal clavicle articulates with sternum and cartilage of 1st rib • Capsule thickened by anterior & posterior SC ligaments Fig 5.2

5. Sternoclavicular (SC) Joint • Great importance because it is the only bony connection between the humerus and axial skeleton • Permits limited motion of the clavicle • Is partially responsible for movements of the scapula • Clavicle movements at the SC joint: elevation & depression, protraction & retraction, and forward & backward rotation

6. Movements Fig 5.3 a & b Protraction (Abduction) Retraction (Adduction) Elevation & Depression

7. Movements Fig 5.3 c & d Upward rotation Downward rotation Upward tilt Reduction of Upward Tilt

8. MUSCLE OF THE SHOULDER GIRDLE • Location: • Anterior • Pectoralis minor, Serratus anterior, Subclavius • Posterior • Levator scapulae, Rhomboids, Trapezius

9. Pectoralis Minor Function: • Movements of scapula: downward rotation, upward tilt, depression • Lifting effect on ribs in force inspiration and posture Fig 5.4

10. Serratus Anterior Function: • Protract scapula • With trapezius upward rotation of scapula • Active is reaching and pushing Fig 5.4

11. Subclavius Function: • Protect and stabilize SC joint • Depress scapula Fig 5.4

12. Levator Scapulae Function: • Elevation and downward rotation of scapula Fig 5.5

13. Rhomboids, Major and Minor Function: • Downward rotation, retraction, & elevation of scapula • With trapezius for maintenance of good posture Fig 5.5

14. Trapezius Function: I. Elevation II. Elevation, upward rotation, retraction III. Retraction IV. Upward rotation, depression, retraction Fig 5.6

15. GLENOHUMERAL (GH) JOINTStructure • Articulation of spherical head of humerus with small, shallow, somewhat pear-shaped glenoid fossa of scapula Fig 5.7

16. GLENOHUMERAL (GH) JOINTStructure • Glenoid labrum deepens the fossa and cushion against impact of humeral head in forceful movements Fig 5.8

17. Ligamentous Reinforcements • Coracohumeral • Glenohumeral • Coracoacromial Fig 5.9

18. Muscular Reinforcements • Above: supraspinatus & long head of biceps • Below: long head of triceps • Front: subscapularis, pectoralis major, & teres major • Behind: infraspinatus & teres minor

19. Movements • Flexion / Extension • Hyperextension • Circumduction • Abduction / Adduction • Horizontal • Diagonal • Inward / outward rotation

20. MUSCLE OF THE SHOULDER JOINT • Location: • Anterior: Pectoralis major, Coracobrachialis, Subscapularis, Biceps brachii • Posterior: Infraspinatus, Teres minor • Superior: Deltoid, Supraspinatus • Inferior: Latissimus dorsi, Teres major, Long head of Triceps brachii

21. Pectoralis Major Function: Clavicular portion – flexion, horizontal adduction, and medial rotation of humerus Sternocostal portion – downward & forward movements of arm, & medial rotation with adduction Fig 5.11

22. Coracobrachialis Function: • Horizontal adduction • Acts like guy wires on mast to stabilize the shoulder joint Fig 5.12

23. Subscapularis Function: • Medial rotation of humerus • Contributes to stabilization of GH joint Fig 5.13a

24. Biceps Brachii Function: • Flexion & Supination of elbow • Horizontal adduction • Short head sometimes in adduction & medial rotation Fig 5.12

25. Deltoid Function: • Powerful abductor of humerus • Middle – Abduction • Anterior – all forward movements of arm & medial rotation of humerus Fig 5.14

26. Supraspinatus Function: • Act together with deltoid in abduction of the arm Also acts in flexion & horizontal extension • Contributes to stabilization of GH joint Fig 5.13b

27. Infraspinatus and Teres Minor Function: • Lateral rotation • With subscapularis depress head of humerus • Contributes to stabilization of GH joint Fig 5.13b

28. Latissimus Dorsi Function: • Extension & adduction of arm Fig 5.14

29. Teres Major Function: • Medial rotation, extension, & adduction of the arm Fig 5.15

30. Triceps Brachii Function: • Long head assists in adduction, extension, and hyperextension of the humerus Fig 5.15

31. JOINT AND MUSCULAR ANALYSIS OF THE FUNDAMENTAL MOVEMENTS OF THE ARM ON THE TRUNK • Movements of the arm on the trunk involve the cooperative action of the shoulder girdle • Acromioclavicular joints • Sternoclavicular joints and the Glenohumeral joint

32. Movements in the Frontal PlaneGH Joint - Abduction • Shoulder Girdle: Upward rotation of scapula Fig 5.16

33. Movements in the Frontal PlaneGH Joint - Adduction • Shoulder Girdle: Reduction of Upward rotation of scapula Fig 5.17

34. Movements in the Sagittal PlaneGH Joint - Flexion • Shoulder Girdle: Upward rotation of scapula Fig 5.18

35. Movements in the Sagittal PlaneGH Joint - Extension • Shoulder Girdle: Reduction of Upward rotation of scapula Fig 5.19

36. Movements in the Sagittal PlaneGH Joint - Hyperextension • Shoulder Girdle: Upward tilt of scapula Fig 5.20

37. Movements in the Horizontal PlaneGH Joint - Lateral Rotation • Shoulder Girdle: Retraction of scapula Fig 5.22a

38. Movements in the Horizontal PlaneGH Joint - Medial Rotation • Shoulder Girdle: Protraction of scapula Fig 5.22b

39. Movements in the Horizontal Plane GH Joint - Horizontal Adduction • Shoulder Girdle: Protraction of scapula GH Joint – Horizontal Abduction • Shoulder Girdle: Retraction of scapula

40. Diagonal Movements • Diagonal forward-downward and slightly inward movement of the arm Fig 5.10 Fig 5.23

41. COMMON INJURIES OF THE SHOULDER REGION These areas may be presented for each injury • Mechanism of Injury (MOI): • How did the injury occur? • Pathology (PATH): • What tissues are damaged? • Sign & Symptoms (S&S): • What does the patient tell you? • What can be determined from an evaluation of the injury?

42. Acromioclavicular Sprain MOI: downward blow to outer end of shoulder • Fall on outstretched hand PATH: tearing or severe stretching of AC ligaments S&S: pain over AC joint • May be laxity of AC joint

43. Fracture of The Clavicle MOI: downward blow to outer end of shoulder • Fall on outstretched hand PATH: Fracture to middle third S&S: Patient supports injured arm • Head may be tilted toward injured side with face turned to opposite side

44. Dislocation of the Shoulder MOI: Arm is forcefully abducted and laterally rotated • May occur by a blow to top of shoulder PATH: Head of humerus is forced out of the glenoid fossa S&S: Arm held out from side in a position of slight abduction and lateral rotation • Loss of normal rounded contour of deltoid muscle

45. Chronic Dislocation of the Shoulder MOI: Congenital abnormality • Repeated acute dislocations PATH: Head of humerus relatively easily come out of the glenoid fossa • Tissue damage due to repeated dislocations S&S: Usually not very painful

46. Rotator Cuff Strains MOI: Overuse • Falling on an outstretched hand PATH: Strains or tearing of rotator cuff muscles • Supraspinatus most often injured S&S: Pain, Inflammation, Weakness