The Shoulder

1. The Shoulder

2. Bones of the Shoulder Scapula spine of scapula glenoid fossa acromion process Clavicle Humerus

3. 4 Joints in the Shoulder Complex • Sternoclavicular joint • Acromioclavicular joint • Glenohumeral joint • Scapulothoracic articulation

5. The shoulder is made for mobility, not stability. The head of the humerus sits in the shallow glenoid fossa.

6. The Muscles of the Shoulder Trapezius – retracts and upward rotation of scapula LatissimusDorsi – adduct, extends, internal rotation of arm

7. Levator scapulae – elevates, downward rotation of scapula • Rhomboids – retraction of scapula • Serratus Anterior – protraction of scapula

8. Deltoid – 3 heads Anterior head – flexes, internal rotation of arm Lateral head – abducts arm Posterior head – extends, external rotation

9. Pectoralis major- clavicular head - adduct, flexes, internal rotation sternal head – adducts, extends, external rotation

10. Pectoralis minor – depresses scapula • Coracobrachialis – flexes and adducts arm

11. Shoulder movements: • Biceps – weak shoulder flexor (long head) • Triceps – shoulder extension

12. What is the Rotator Cuff? The rotator cuff is a group of 4 muscles that helps to lift your shoulder up over your head

13. The Cuff Muscles • Subscapularis: shoulder internal rotation

14. Infraspinatus - shoulder external • Teres Minor - rotation Infraspinatus is the most powerful external rotator

16. Supraspinatus- helps deltoid abduct the shoulder-most commonly injured cuff muscle

17. Apley’s Scratch Test

20. The Throwing Motion http://www.youtube.com/watch?v=I_bYlY6AHew

21. Humans are unique in their ability to throw at high speeds with great accuracy • Why? • Store elastic energy in our shoulders (cocking) • When released, this energy produces rapid rotation of the arm – the fastest motion we produce – 9000 degrees/sec in pro. Pitchers

22. Evolution – 3 anatomical shifts about 2 million years ago • Expansion of waist – allows torso to rotate independently from waist • Lowering of the shoulders – allows muscles to store more energy • Low humeral torsion – allows more stored energy • These allowed us to be more successful hunters

23. Throw a football harder http://search.espn.go.com/sport-science/videos/under-2-minutes/6-85 Throw a baseball Farther http://search.espn.go.com/sport-science/videos/under-2-minutes/6-85 Drew Brees Accuracy http://www.youtube.com/watch?v=g4vDZ_OquS8&feature=related Tim Tebow http://www.youtube.com/watch?v=5AsbCFNauAw Baseball vs. Softball http://www.youtube.com/watch?v=_de3HJvO-N8

24. 1. Wind-up • 2. Cocking Phase • 3. Acceleration Phase • 4. Ball Release • 5. Follow-through • http://www.youtube.com/watch?v=fTi6fQ22sH0 • http://www.youtube.com/watch?v=BhNmUv4XkyU&feature=related

25. Acute Injuries Fractures Dislocations Subluxations Sprains/Strains Contusions Overuse Injuries Impingement Instability Tendonitis Bursitis Shoulder Injuries

26. “Winging of the Scapula” usually due to a weakness in the serratus anterior muscle or injury to the long thoracic nerve http://www.youtube.com/watch?v=HepHiQOsT-E

28. Biceps Tendon Rupture • More than 90% occur proximally • The rest occur distally at the elbow • http://www.youtube.com/watch?v=Wjq82nYPUeo • http://www.youtube.com/watch?v=yCP9svqIY2s

30. Contusions • “Shoulder Pointer” – contusion to bony prominence of shoulder (acromion process)

31. Fall on outstretched arm Direct impact Rotational force http://www.youtube.com/watch?v=krZ0CGx4wWE Humeral Fractures

32. http://www.youtube.com/watch?v=LmMhoNIQM-I http://www.youtube.com/watch? v=ixrmplBtC5E v=ixrmplBtC5E 80% midclavicle 15% distal/5% prox Fall on outstretched arm or tip of shoulder Figure 8 strap Clavicle Fracture

33. Scapula fracture • Uncommon in athletics • Direct impact • Very high incidence of other structures being injured

34. Shoulder Aneurysm – David Cone • Ballooning of an artery • Blood clots that formed in the aneurysm near the shoulder apparently broke off and blocked blood flow, causing tingling and pain in his fingers and making his ring finger turn white. • Cone's aneurysm was in a branch of the posterior circumflex humeral artery

36. Anterior Dislocation more common Clavicle protrudes anteriorly Quick recovery Posterior Dislocation potential injuries to vessels, esophagus, trachea May have hoarseness or difficulty swallowing Sternoclavicular Dislocation

39. Acromioclavicular Sprain (AC) • “shoulder separation” • Fall on outstretched arm or tip of shoulder • + piano key sign • Pain with horizontal adduction and abduction over 90o

42. Anterior Dislocation Occurs with external rotation/abduction of shoulder Head of humerus lies in chest/anterior armpit Indentation of the deltoid – Sulcus Sign First time dislocations – high possibility of nerve injury or fracture Posterior Dislocation - Humeral head lies in the posterior shoulder - Shoulder is held in internal rotation and cannot be externally rotated Shoulder Dislocation

45. Shoulder Impingement • With prolonged repetitive overhead throwing motion, the rotator cuff may impinge on the acromion and coracoacromial ligament

46. Shoulder Impingement Signs and Symptoms • Pain with external rotation and abduction • Pain/weakness in rotator cuff • Discomfort with horizontal flexion, flexion, and internal rotation

48. Chronic Rotator Cuff Tears Occur from degeneration of cuff tendon due to: • Poor blood supply • Repetitive activity

49. Chronic Rotator Cuff Tears • Small tears – rest and rehab for 4-9 months, ROM exercises, cuff exercises • Surgery may be required