1. Injuries in the Throwing Shoulder David Conner MD OrthoNortheast 4/25/15

2. Patient Population Throwers Volleyball Swimmers Tennis Player

3. The Thrower Concept of kinetic chain –Legs and trunk-> generate power –Shoulder->funnel and force regulator –Arm-> force delivery system

4. The Throwing Shoulder Perfect balance of mobility & stability “Thrower’s Paradox” –Lax enough to allow excessive external rotation, but stable enough to prevent recurrent subluxation

5. The Set Point or Slot Excessive ER generates the velocity Throwers know ER “set point” to throw hard---known as “The Slot”

6. Phases of Throwing Late cocking- 165 degrees ER, 300 N anterior shear force Acceleration phase- 7,300 degrees/sec angular velocity Deceleration- 1000 N distraction force

7. Potential for Disaster Significant motion Significant forces

8. Problem of the Throwing Shoulder “Dead Arm Syndrome” –Any pathologic shoulder condition where the thrower is unable to throw with preinjury velocity and control because of combination of pain and subjective unease SLAP lesion Internal Impingement Cuff tear

9. SLAP Lesions ( Superior Labrum Anterior to Posterior) Snyder Classification

10. Internal Impingement Contact of Supraspinatus/infraspinatus & posterior- superior labrum in ABER (abduction/ external rotation) ? Physiologic or pathologic Humeral Retroversion Crockett et al, AJSM, 2002 CT Scans bilateral shoulders Humeral retroversion –Dom = 40 deg –Non dom = 23 deg. Mean Diff between ER & IR Dom and Non dom, 7 & 9 deg

11. Dead Arm Syndrome: Theories Frank Jobe –Excessive ER causes micro stretch of anterior capsule –Anterior instability causes internal/external impingement –Internal Impingement causes SLAP lesion Burkhart & Morgan –Posterior capsule problem –SLAP lesion cause dead arm –No anterior instability present

12. Dead Arm Syndrome: Jobe Model Hyperangulation in ABER-Humerus left behind scapula Tensile overload of anterior capsule-subluxation

13. Dead Arm Syndrome: Jobe Model Muscles fatigue leading to pathologic internal impingement and subacromial impingement Secondary labral or cuff tears

14. Jobe Model Treatment-Eliminate anterior laxity –Surgical results Open capsular shift-> 50% return to play Halbrecht –Anterior instability DECREASES internal impingement

15. Burkhart-Morgan Model Posterior capsular tightness Posterior-superior instability “Peel-back” mechanism-SLAP Anterior pseudoinstability Internal impingement Result: SLAP & cuff pathology

16. Throwers Develop Increased ER in Abduction Humeral retroversion Soft tissue adaptation Gain in ER should equal loss of IR Need 180 degree total arc

17. G.I.R.D Glenohumeral Internal Rotation Deficit Loss of ER compared to nonthrowing side Posteroinferior capsular contracture –THE ESSENTIAL LESION

18. GIRD Posteroinferior capsular tightness –Posterior band of inferoglenohumeral lig. –Traction phenomenon

19. GIRD-Tethered shoulder Ant IGHL & Post IGHL act as sling

20. GIRD-Tethered Shoulder Tight post IGHL tethers contact point –Moves pivot posterosuperiorly –Allows GT to clear glenoid-> increases ER

21. Tight posteroinferior capsule –Hyper ER –Hyper horizontal ABD –Drop elbow –Premature trunk rotation

22. GIRD & Anterior Pseudolaxity Result: Able to increase ER by clearing GT and effective laxity of anterior capsule  Get to “The Slot”

23. GIRD & The Slot With GIRD, increase in ER puts major stress on structures –Biceps anchor –Labrum –Cuff

24. “Peel-Back” Mechanism ABER-> biceps vector moves vertical and posterior –Torsion to posterior superior labrum –Posterior Type II SLAP

25. Peel-Back

27. SLAP Repair Simple suture at root better than tacks Repair SLAP, eliminates anterior pseudo laxity  DO NOT NEED ANTERIOR STABILIZATION

29. SLAP Lesions Surgical debridement –Cordasco 1993 27 pts 2 yr 63% G/E 45% return to sport –Altcheck 1992 70% moderate pain @ 2 years

30. SLAP Lesion Repair with Suture Anchor –Burkhart 2000 124 pts 2 yr 90% excellent 10% good 100% pitching @ 2 yrs

31. Dead Arm & the Rotator Cuff Tension Compression—Internal Impingement Result: Partial Thickness Articular Sided RTC Tear

32. Dead Arm and RTC 31% of throwers with SLAP have RTC tear –38% were complete RTC –62% were PTRTC

33. The Problem Tight posterior capsule->posterosuperior shift-> Increased ER->Peel-back->Internal impingement/traction-> Cuff tear=Dead Arm Answer: Prevent Posterior capsular tightness

34. GIRD - Treatment Non-op

35. GIRD Non operative Treatment 90% throwers with symptomatic GIRD > 25 degrees respond to stretching in 2 weeks Best responders—young patients

36. GIRD - Treatment Operative Glenoid Capsule

37. Conclusion Dead arm- difficult clinical & radiographic diagnosis. Confirmed at arthroscopy Culprit- GIRD Best treatment- Prevention If symptomatic, SLAP usually present Look for cuff pathology Anterior laxity may exist, but don’t treat as initial problem

38. Young Throwing Shoulder Pain – not normal

40. Common Problems Little League shoulder Mild instability Rotator cuff tendonitis

41. Little League Shoulder Adams, Calif Med 1966 –“osteochondrosis of proximal humeral physis” Ages 11-14 –Time of maximal prox humeral growth Rotational forces disrupt hypertrophic zone of physis –external rotation torque is estimated to be approximately 18 Nm 400% that physeal cartilage can take –distraction force estimated to be approximately 214.7 Nm 5% of what physis can tolerate –bone is much stronger in tension than with rotational stresses

42. X-rays Widening of physis, metaphyseal demineralization and fragmentation, and periosteal reaction

44. Little League Shoulder Physeal widening can persist after symptoms resolve

45. MRI widening High intensity signal change adjacent to physis

46. Treatment Relative rest (sling?) No throwing 2-3 mos Anti-inflammatory meds Controlled return once asymptomatic Pitch Count Rehab -Strengthen Trunk

47. Pitch Count Guidelines Rest requirements –>61 pitches  3 days –41-60  2 days –21-40  1 day –0-20  0 days rest League Age –17-18 105 pitches per day –13-16 95 pitches per day –11-12 85 pitches per day –9-10 75 pitches per day –7-8 50 pitches per day

48. Carson & Gasser. Little leaguer’s shoulder. A report of 23 cases. Am J Sports Med 1998; 26:575–580. Excellent results protocol for return to play mentioned previous slide 21 of 23 patients (91%) were able to return to baseball at an average of 3 months (range: 1 month to 1 year) with asymptomatic shoulders Largest series to date

49. Prevention Information / education Fitness exercises = general basis for all sports participation Avoid specialization Begin training early (before season) No more than 10% increase each week