This document summarizes a presentation on AC joint and distal clavicle injuries. It discusses the classification of AC joint injuries, controversies around treatment of type III injuries, surgical techniques for repair and reconstruction, and recent biomechanical studies. While the literature is limited, current evidence suggests conservative treatment may be adequate for many type III injuries, with surgical intervention favored for more active patients or overhead athletes. Surgical techniques like the tightrope and anatomic reconstruction show promise but further research is still needed.

1. AC Joint Injury Update
Cherry Blossom Seminar
April 6, 2013
J.R. Rudzki, MD
Washington Orthopaedics & Sports Medicine
Clinical Assistant Professor
Dept. of Orthopaedic Surgery
George Washington University School of Medicine
Washington, DC

2. Disclosure
Previous direct & indirect funding & support for
research & education from:
• Philips Medical Imaging
• Bristol-Myers-Squib
• Smith & Nephew
• NIH (CT Chen)
• HSS Institute for Sports Medicine Research
• Major League Baseball
Arthrex – Consultant
AJSM, JBJS – Reviewer
AAOS – Evaluation Committee

3. Introduction Background
High incidence of distal clavicular & A-C injuries in contact
sports at all levels.
Flik et al., AJSM 2005
Frequently amenable to
conservative management
Controversy regarding operative indications for
Type III AC Separations & Distal Clavicle Fractures
Potentially significant cause of
missed time from play
Emery et al., AJSM 2006
AC Separation & Dislocation:
- up to 40% of shoulder injuries in
elite athletes participating in
competitive contact sports
Mazzocca et al., AJSM 2007

4. • Resist 90% of A-P translation
& joint distraction
Fukuda et al., JBJS 1986; Klimkiewicz et al., JSES 1999
• Horizontal Stabilizer
• At large displacements, Trapezoid resists ~75% of AC joint
compression & Conoid is primary restraint to superior translation
• Vertical Stabilizer
Ligamentous Anatomy Background
• Posterior & Superior AC capsular
ligaments provide greatest stability
- clinically impt for distal clavicle resection

5. Newer Studies
Better Data
Enhanced Understanding of
Anatomy & Biomechanics
2013
Broader Array of Repair
& Reconstructive Options
Technological
Advances
More impt than ever to be clear on
indications for surgery & best approach
for each patient

6. Radiographic Assessment
 AP
– 1.1-1.3 cm from
coracoid to clavicle
 Zanca
– 10-15° cephalad
– AC joint 0.5-3mm
 Axillary
– Anterior or posterior
displacement
Tauber & Resch et al., AJSM 2010

7. A-C Joint Injury Classification
Nuber & Bowen, JAAOS 1997
Williams GR, Nguyen VD, Rockwood CA Jr.
Classification and radiographic analysis of
acromioclavicular dislocations. Appl Radiol. 1989;12:29-34
Type I - AC ligament complex sprain
without ligamentous disruption
Type II - disruption of AC ligament
complex & capsule, up to 50%
vertical subluxation of distal clavicle
Type III - both AC & CC ligaments
disrupted, complete dislocation of
AC joint
Type IV - distal clavicle displaced
Posteriorly
Type V - extreme superior
displacement of clavicle (100%-300%)
complete disruption of delto-trapezial
fascia distally
Type VI - distal clavicle displaced
Subcoracoid or Subacromial

8. Types I & II
Conservative
Mgmnt
Sling x 1-2 wks
Passive Supine FE, ER
Gradual Progression to
AAROM
Return to Play ~2-6wks
AC Separation / Dislocation
Type III
Acute
*** Index of Suspicion
for Concomitant Intra-
articular Pathology ***
Berg et al.,
Arthroscopy 1997
Gladstone & Wilk et al.,
Oper Tech Sports Med, 1997
Role of
NSAIDs?

9. Types IV-VI
AC Separation / Dislocation
• Mod Weaver-Dunn +/- Graft
• Open Anatomic Reconstruction
• (Mazzocca Technique)
• Arthroscopic Reconstruction
Operative
Treatment
Type III
Chronic
&
Symptomatic

10. Treatment trends:
Schlegel T, et al.
Grade III acromioclavicular
separations in NFL quarterbacks.
NFL Physicians Annual Meeting.
Indianapolis; 2000.
–8 professional quarterbacks
over 10 yr period
–5 returned to play in 5 wks
treated conservatively
–3 required surgical treatment
Controversy Regarding Type III Outcomes

11. Controversy Regarding Type III Outcomes
Study Design: 20 pts with Grade III injuries followed for one
year with strength assessment & subjective questionnaire
•17 men, 3 women; Avg Age =36
• Variable age, work, & recreational activity levels
• Compared to 10 uninjured “controls”
Schlegel et al., AJSM 2001
• 16/20 pts (80%): “acceptable” outcome at one year
• 4/20 (20%): poor outcome; did not warrant surgical intervention
Results:
• 17% weaker on injured extremity 1 year after injury (Bench Press)
• But No difference in Rotational Strength

12. Controversy Regarding Type III Outcomes
Literature Review –
Swinging Pendulum
• Powers, CORR, 1974: 82% of Residency
Chairman treat Type III injuries operatively
• McFarland, Am J Orth, 1997: 69% of 42 MLB Team Physicians
Conservative Tx for professional throwers; 31% Operative Tx
• 80% of 20 Pitchers treated non-operatively – Full Fxn & Pain-Free
• 92% of 12 Pitchers treated operatively – Full Fxn & Pain-Free
• Phillips, CORR, 1998: 1172 pts studied in Meta Analysis
• 88% Operative
• 87% Conservative
Satisfactory Outcomes

13. Controversy Regarding Type III Outcomes
Literature Review
• Tibone, AJSM, 1992: 20 pts, Nonop Tx for Grade III
• No strength difference btwn injured/noninjuried UE’s
• 31% reported mild pain but “did not limit participation”
• Wojtys & Nelson, CORR, 1991: 22 pts,
Nonop Tx for Grade III
• No strength difference btwn injured/noninjuried UE’s
• 50% rated outcome as fair or poor
• Larsen, JBJS, 1986: 41 pts, Prospective Randomized
• No clinical difference in outcome
• Non-surgical patients returned to work earlier

14. Is there a single “right” answer?

15. Limitations of Literature
Difficult to define optimal management of these
injuries based on currently available literature
Numerous
• Small sample sizes; variable inclusion/exclusion criteria
• Short Follow-Up
• Retrospective Reviews, Case Series, Surveys…
• Recall Bias • Selection Bias
• Non-validated Outcomes Instruments
• Detection Bias
• Susceptibility Bias

16. Only 9 of 469 articles compare
Operative vs. Non-Operative Tx:
• 3 Prospective, Randomized Studies (Level II)
• 6 Retrospective Studies
CORR, 2006
Current Consensus:
While the treatment of Type III injuries remains controversial, the
data currently available indicate that the two treatments may be
equivalent, but non-operative management may be favorable for
its decreased risk of complications

17. Types I & II Types IV-VI
Conservative
Mgmnt
Sling x 1-2 wks
Passive Supine FE, ER
Gradual Progression to
AAROM
Return to Play ~2-6wks
AC Separation / Dislocation
• Mod Weaver-Dunn +/- Graft
• Open Anatomic Reconstruction
• (Mazzocca Technique)
• Arthroscopic Reconstruction
Operative
Treatment
Type III
Chronic
&
Symptomatic
Acute

18. Mark Stuart

19. AAOS, 2013

20. AC Injury Summary
Key Take-Home Points
• Some advocate surgical intervention for
Type III & V in:
• Types I-III, V: Good-Excellent Results in
majority of players at all levels
• Minimal Functional Deficit, if any
• Relatively Rapid Return to Play
• Delayed reconstruction available if symptomatic
• Types IV & VI: Surgical intervention indicated
• Overhead athletes
• Laborers
• High-demand individuals

21. Growing body of evidence to support move away
from Modified Weaver-Dunn
Prospective cohort study of 24 pts
Mean F/U: 37 months
ASES & Constant Scores better in ST Graft Group (P<0.05)
Stress-loading more favorable in ST Group (P<0.05)
Non-anatomic
Less stable reduction
AJSM, 2009
Semitendinosus graft resulted in significantly superior clinical
& radiologic outcomes compared to modified Weaver-Dunn

22. In this study, better results were achieved by surgical treatment
with the hook plate.
Retrospective case-control study, 50 pts (82% follow-up @ 34 mos.)
24 pts – Hook Plate vs. 17 pts – Conservative Mgmt
Oxford & Constant Scores, SST
Stress Radiographs
Hook Plate Non-operative
Constant
Score
90.4 80.7
Mean CC
Distance
(stress XR)
12.1 mm 15.9 mm
(P <.05, Mann-Whitney U test & Student’s t test)
Gstettner & Resch et al., JSES 2008
Conclusions:

23. “pts were told that there were no evidence-based medical guidelines for treatment of
Rockwood type III injuries on the whole but that,
in the international literature, surgery was
recommended in young, active patients with high
demands on shoulder function.”
Retrospective case-control study, 50 pts (82% follow-up @ 34 mos.)
24 pts – Hook Plate vs. 17 pts – Conservative Mgmt
Oxford & Constant Scores, SST & Stress Radiographs
Gstettner & Resch et al., JSES 2008
Complications: 1 Hematoma
2 Infections (1 superficial)
1 Acromial Osteolysis
17%

24. Cadaveric Study, 2 Groups
- 60 matched pairs (Hamann-Todd)
- 19 fresh-frozen shoulders
Distance from lateral clavicle to medial
conoid tuberosity: ~45 mm (P < .05)
Distance to center of trapezoid
tuberosity: ~ 25 mm (P < .05)
Mazzocca et al., AJSM 2007
Background

25. JSES, 2009
Ligamentous Anatomy & Reconstruction
Resection of distal clavicle may be detrimental
Repair of AC Capsule appears to be beneficial
Biomechanical study, 6 matched pairs
Measurement of AC Joint Translation: AP & Superior-Inferior
- Compressive & Translational Loading
- AC & CC Ligament transection
Compression significantly decreased translation (P<0.05)

26. Biomechanical study, 5 cadaveric shoulders
Static loads (80 & 210 N) applied to
clavicle in 5 directions:
anterior, anterosuperior, superior,
posterosuperior, & posterior
in situ graft force measured:
1) intact AC ligaments
2) sectioned AC ligaments
3) distal clavicle excision
AJSM, 2010

27. Biomechanical study, 5 cadaveric shoulders
Static loads (80 & 210 N) applied to
clavicle in 5 directions:
anterior, anterosuperior, superior,
posterosuperior, & posterior
Distal clavicle excision
did not further increase
in situ graft forces
Distal clavicle excision
increased in situ
graft forces
For both magnitudes of load, in all directions,in situ graft
force with intact AC ligaments was significantly less (P<.001)
AJSM, 2010
Reconstruction of AC ligaments may serve impt role in
decreasing in situ graft force during healing

28. Surgical Techniques - Tightrope
Salzmann et al., AJSM 2010
Consecutive case series, 23 pts
Type III-V AC Injuries
Mean F/U: 31 months Mean Age: 38
VAS, Constant Score, SST, SF-36
VAS & Constant score showed significant
improvements from preoperative 4.5 +/- 1.9
and 34.3+/- 6.9 to postoperative 0.25 +/-
0.5 and 94.3 +/- 3.2 at 24 months,
respectively.
Postop radiographic AC alignment was
unsatisfactory in 8 cases with no different
clinical outcome when compared with the
remaining patients

29. Surgical Techniques - Tightrope
Salzmann et al., AJSM 2010
Consecutive case series, 23 pts
Mean F/U: 31 months Mean Age: 38
Tunnel and button placement are of utmost importance
to avoid postoperative failure or loss of reduction.
Immediate anatomical reduction of an acute AC
separation with flip-button devices provides
satisfactory clinical results at intermediate-term
follow-up.
1 Infection
1 Coracoid Fracture
1 Implant Failure
(?non-compliance)

30. Surgical Techniques - Graftrope
Preliminary Study
•10 Cases, 6 month F/U
• No infxn, hardware/graft failure,
or loss of reduction
Deberardino et al., JSES 2010

31. Surgical Techniques - Graftrope

32. Surgical Techniques - Graftrope

34. Surgical Techniques – Anatomic Reconstruction
Biomechanical Study; 30 Cadaveric Specimens
• Modified Weaver-Dunn
• Nonanatomic allograft
• Anatomic allograft
• Anatomic suture
• GraftRope
5 Groups + Control:
AJSM, 2011
Conclusion:
The anatomic allograft reconstruction has superior initial
biomechanical properties by comparison
Highest
load to failure
(P < 0.05)
2nd Highest
load to failure (646 N vs. 948 N)

35. Surgical Techniques – Anatomic
Reconstruction
• Anatomic Studies
• Biomechanical Data
• Limited Clinical Data
Current Data:

36. Not Currently a Clear Choice
AJSM, 2012
Level IV Case Series – 27 cases: 10 = Coracoid Tunnel & 17 = Loop
8 complications (80%) in Coracoid Tunnel Group:
- 2 coracoid fractures (20%)
- 5 pts with loss of reduction (> 5-mm increased CC interval displacement
on subsequent postop radiographs) (50%)
- 1 pt with an intraoperative failure of the coracoid button (10%).
6 pts developed complications in Coracoid Loop Group (35%):
- 3 clavicle fractures (18% within group, 11% overall)
- 2 pts with loss of reduction (12%)
- 1 infection (6%)
- 1 pt with adhesive capsulitis

37. AJSM, 2012
Level IV Case Series – 28 cases: 14 = Open & 14 = Scope-Assisted
Overall failure rate was 28.6% (8/28) at avg of 7.4 wks postop
Medialized bone tunnels were a significant predictor for early loss of reduction

38. Biomechanical Study; 6 Cadaveric Pairs
Mean AP translation of CC/AC reconstruction
50% or less than that of the CC reconstruction
in all loading conditions (P < .05)
No Difference for:
Mean superior-inferior translation
Overall load-to-failure testing
Intramedullary AC complex reconstruction utilizing free-tissue graft
for both CC & AC ligaments demonstrates significantly greater
initial horizontal stability & is similar to intact specimens
Conclusions:
AJSM, 2010

39. Future Questions
• Graft Fixation
• Tunnel Size & Placement
• Coracoid Fracture Risk
• AC Capsular Reconstruction

40. AC & Distal Clavicle Injury Update
Cherry Blossom Seminar
April 6, 2013
J.R. Rudzki, MD
Washington Orthopaedics & Sports Medicine
Clinical Assistant Professor
Dept. of Orthopaedic Surgery
George Washington University School of Medicine
Washington, DC
Thank
You