June 11, 2013

1. June 11, 2013

2. Joseph C McCormick III, MD Orthopaedic Surgeon Affinity Medical Group

3. Disclosure Slide • Nothing to disclose in terms of financial or industry relationship.

4. Goals • Review anatomy of acromioclavicular joint • Mechanism of injury • Classification of acromioclavicular injuries • Define treatment based on grade • Review of clinical outcomes and biomechanical literature regarding AC Injury

5. History • Hippocrates first to distinguish AC injuries from GH joint injuries and to delineate the mechanism of injury • “Physicians are particularly liable to be deceived in this accident, so that they may prepare as if for dislocation of the shoulder;…”

6. History • Galen diagnosed his own AC dislocation sustained while wrestling • Treated himself as Hippocrates suggested with tight bandages to hold clavicle down with arm elevated • Abandoned this treatment after a few days because it was so uncomfortable • Hippocrates felt that no “impediment, great or small will result from such an injury” • Furthermore he stated the deformity cannot be restored to its “natural situation” • This statement has been received by the ortho community over the years as a challenge. • First reported surgical procedure for AC dislocation by Cooper in 1861

7. Anatomy • Diarthrodial joint • Has fibrocartilaginous disk • Clavicle rotates with external rot and abduction • AC ligaments stabilize in AP direction, insert on clavicle 1.5 cm from joint – superior and posterior fibers most robust • CC ligaments – predominant restraint to vertical translation

8. Anatomy • Coraco-clavicular Interval: average 1.1 - 1.3 cm • Trapezoid: attaches anterior and lateral on clavicle • Average distance distal clavicle to center 2.54 cm males/ 2.29 cm females • Conoid: attaches posterior and medial on clavicle • Larger of the 2 CC ligmaments • Next ligament to fail after AC ligament disruption • Ave distance distal clavicle to medial aspect of conoidtuberosity 4.72 cm males/ 4.28 cm females OKU 4 Sports Medicine

9. Dynamic stabilizers • Muscles that cross joint important to stability • Anterior deltoid helps to suspend arm from clavicle attachment • Trapezius has confluent fascial attachment over dorsum of acromion • Importance noted in the higher grades of injury, i.e.. Type V

10. Mechanism

11. Direct vs. Indirect • Direct by far most common • Direct force to acromion with the shoulder adducted, usually result of fall • Acromion moves inferiorly and medially while clavicle is stabilized by the SC joint ligaments • Force results in systematic failure of stabilizing structures as it propagates • AC ligaments/capsule • CC ligaments • deltotrapezial fascia • Indirect is more rare • results from fall onto outstretched hand/arm with superiorly directed force • typically affect AC ligaments only

12. Diagnosis During exam should be sitting or standing w/o support for the injured arm Check for tenderness to palpation at the AC joint and the CC interspace If patient can tolerate check joint for stability Check to see if reducible Examine SC joint as well Neurologic exam to r/o brachial plexus injury

13. Radiographs AP, axillary lateral and Zanca views can be taken to best assess the joint Should be taken with the patient upright and no support of injured arm Stress views ??

14. Stress Radiographs ? • Stress views are costly, painful, and don’t often provide new info, so aren’t routinely used anymore ASES Survey 81% Not in ER 91% No change in Treatment

15. Radiographs • Zanca View • Underpenetrated view • 10-15 degree cephalic tilt • Axillary View • Assess horizontal displacement

16. Biplanar Instability/Displacement Vertical Horizontal

17. Dynamic Axillary View Tauber et al AJSM 2010 Gleno-acromio-clavicular angle May help detect previously missed horizontally unstable injuries.

18. Classification Originally described by Tossy and Allman in the 1960’s Included types I,II, and III In 1984, classification modified by Rockwood Now types IV, V, and VI added, better predictor of prognosis, need for surgical intervention

19. Type I • No visible deformity • Swelling/pain over AC joint • No pain over CC interspace • Radiographs appear normal

20. Type II • AC ligaments disrupted • Horizontally unstable • Absent or very minimal vertical instability • Tenderness over CC interspace • Abnormal radiographs

21. Type III • Horizontal and vertical instability • Radiographically AC joint is dislocated • Pain in CC interspace • Typically pain is greater with Type III and higher injury • Historically more debate with choice of treatment

22. Type IV • AC joint dislocation • Clavicle displaced posteriorly • AC joint irreducible on exam • Occasionally associated with SC dislocation

23. Type IV

24. Type V • All stabilizing ligaments disrupted • Deltoid and trapezius muscles and fascia at least partially detached from clavicle • AC joint irreducible • May develop symptoms due to brachial plexus traction

25. Type V

26. Type VI • High energy variant • Result of hyperabduction and external rotation • Distal clavicle comes to rest in subcoracoid position

27. Summary

28. Treatment I and II • Nonsurgical management is uniformly recommended for type I and II injuries • A period of immobilization in a sling for comfort until pain subsides • Usually 7-10 days for type I, up to 2 weeks for type II • Possible anesthetic injection for return to high level play • Unloading foam padding • Once acute pain has subsided rehabilitation program is instituted

29. Not So Benign? • Mouhsine et al JSES 2003 • 33 patients Grade I and II injuries treated conservatively • 27% required surgery within 36 months (6 distal clavicle excision, 3 Weaver-Dunn) • 24 pts remaining assessed 6 yrs post injury both clinically and radiographically • Only 16% patients with no radiographic degenerative changes or osteolysis evident

30. Not So Benign? • Mikek AJSM 2008 • 23 patients with Type I and II AC Disruption with 10 year Follow-up • 52% reported occasional symptoms • Constant score 70.5 injured vs 86.8 (P < .001) • UCLA score 24.1 vs 29.2 (P < .001) • Simple Shoulder Test 9.7 vs 10.9 (P < .002)

31. Rehabilitation Early focus is on passive and active ROM Once symmetric and painless ROM achieved then progress to isometric shoulder strengthening Isotonic strengthening is next with gradual escalation of strength and endurance with return to sport in mind Return to sport is not allowed until painless/full ROM is achieved and strength has returned. This may take longer for type II injuries, and some recommend contact sports/heavy lifting should be avoided for 2-3 months

32. What about Type III injuries?

33. Type III injuries • In 1974 Powers and Bach reported that 92% of 116 type III injuries were treated operatively • Of 163 ortho residency program chairmen surveyed at that time 91.5% advocated surgical treatment • In 1992 Cox surveyed 231 chairmen and 62 orthopedists participating in care of athletes • 72% of chairmen favored non-op management • 86% of team orthopedists favored no-op management • trend toward non-surgical management is well supported in the literature

34. Natural History of Type III • Schlegel et al AJSM 2001 • Prospective study non-operative treatment of 20 patients with Type III AC injuries assessed strength, ROM, subjective questionnaire • Ave Sling use: 8 days (2-25) • Ave return to work: 9 days (1-24) • 7 professionals, 8 laborers, 2 students, 3 unemployed/retired • Analgesic discontinued: 1 wk (15); 2 wk (5)

35. Natural History of Type III • Schlegel et al 1 year results • All had full, pain free, symmetric ROM • No statistical difference in dynamometer strength • A statistically significant 17% decrease in bench press strength on injured side was noted • 80% favorable subjective results • 20% unfavorable • 3 of 4 secondary gain bias • Only 1 of 4 elected to undergo surgical intervention

36. Non-op management • Galpin et al 1984, retrospective review comparing outcome in type III injuries, 21 treated non-op, 16 with surgery (Bosworth screw and ligament repair) avg 3 yr f/u • Showed overall chances of late pain or altered function were not statistically different • Surgical patients took longer to become pain free, and longer to return to work • 2.8 vs. 4.5 months, and 2.6 vs. 6.8 weeks, respectively • Numbers were limited to correlate treatment with patient demands • Glick et al 1977, retrospective review of 35 AC dislocations treated non-operatively. • 29/35 had no pain, none had disabling pain, 31/35 had no weakness, none had disabling weakness • None of the patients who had supervised rehabilitation complained • 8/10 throwers were not affected while throwing, two were professional quarterbacks and one a collegiate javelin thrower • Concluded that complete reduction not necessary for satisfactory function

37. Randomized prospective trial • Bannister et al 1989 – 60 patients with acute AC dislocations random number drawn to allocate operative vs. no-op treatment • Faster return to work for manual and clerical workers treated non-operatively • After 4 years of f/u no real difference between the two groups in terms of pain/function with one exception • In the 12 dislocations with more severe dislocation, i.e.. Type V, surgery gave better results • Concluded that younger patients with severe displacement are more likely to achieve an excellent result if stabilized early • Felt that surgical treatment created greater morbidity in the lesser grades of injury

38. Slight strength loss? • Wojtys et al, 1989, retrospective review of 22 patients with type III treated non-operatively • Showed that laborers and athletes can recover strength and endurance, return to pre-injury level of activity without surgery • Strength testing showed some statistically insignificant strength loss, indicating that the strength and endurance advantage one might expect of the dominant arm may be lessened or lost • May be a factor to consider for those requiring high levels of shoulder strength for work/athletics, or those involved in highly repetitious endurance activities such as swimming/pitching • Rarity of type III AC separation precludes study of significant numbers with controls to determine treatment that is best for athletes who rely on their elite throwing ability

39. McFarland MLB Survey Study 1997 American Journal of Orthopedics, Nov 1997

40. Phillips et. al CORR 1998 Meta-analysis Type III AC Injury OP vs NON-OP Pain absent or minimal 93% 95% ROM normal/near normal 86% 95% Strength normal /near normal 87% 91% Subsequent surgery 59% 6%

41. Operative results and Timing • Weinstein et al AJSM 1995 • 44 patients Type III Injury • 27 acute, 17 late repairs • CC nonabsorbable suture repair/recon • 15/27 and 17/17 CA transfer • 89% satisfactory results, 93% return to sports • Timing Acute (<3 wk) vs Late (> 3wk) • Satisfactory results 96% vs 77% • Loss of reduction 15% vs 29%

42. Types IV, V, IV All require operative intervention All stabilizers, static and dynamic are injured

43. Treatment Old School Not well tolerated, Dermal Complications

44. Surgical management Fixation across AC joint Fixation between coracoid and clavicle Ligament reconstruction Distal clavicle excision

45. Acromioclavicular Fixation • Pin fixation • Has been abandoned since reports of rare pin migration • Heart, Lung, Great vessels

46. Acromioclavicular fixation Hook Plate Only used for acute injury Requires subsequent surgery for removal

47. Fixation between coracoid and clavicle Bosworth popularized the use of a screw for fixation of the clavicle to the coracoid This technique initially did not include recommendation for repair or reconstruction of the CC ligaments Today the use of screws and suture loops has been described alone and in combo with ligament reconstruction Placement of synthetic loops between the coracoid and clavicle can be done arthroscopically, main advantage: doesn’t require staged screw removal

48. Ligament reconstruction Weaver and Dunn were the 1st to describe transfer for the native CA ligament to reestablish AC joint stability Their technique described excision of the distal clavicle with this ligament transfer Construct can be augmented with a suture loop for protection until the transferred ligament heals

49. Ligament Reconstruction orthoillustrated.com Open and Arthroscopic techniques Restore Anatomy

50. Anatomic Ligament Reconstruction • Alternative technique is use of semitendinosusautograft for reconstruction • Loop around or fix into coracoid, then fix through two separate clavicle bone tunnels to approximate normal anatomic location of CC ligaments • Recent biomechanical studies have demonstrated the superiority of this construct