June 11, 2013
Joseph C McCormick III, MD
Orthopaedic Surgeon
Affinity Medical Group
Disclosure Slide
• Nothing to disclose in terms of financial or
industry relationship.
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
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;…”
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
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
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 conoid tuberosity 4.72 cm
males/ 4.28 cm females
OKU 4 Sports Medicine
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
Mechanism
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
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
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 ??
Stress Radiographs ?
ASES Survey
81% Not in ER
91% No change in
Treatment
Stress views are costly,
painful, and don’t often
provide new info, so aren’t
routinely used anymore
Radiographs
Zanca View


Underpenetrated
view
10-15 degree
cephalic tilt
Axillary View

Assess horizontal
displacement
Biplanar
Instability/Displacement
Vertical
Horizontal
Dynamic Axillary View
Tauber et al AJSM 2010
Gleno-acromio-clavicular angle
May help detect previously
missed horizontally unstable
injuries.
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
Type I
No visible deformity
Swelling/pain over AC
joint
No pain over CC
interspace
Radiographs appear
normal
Type II
AC ligaments disrupted
Horizontally unstable
Absent or very minimal
vertical instability
Tenderness over CC
interspace
Abnormal radiographs
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
Type IV
AC joint dislocation
Clavicle displaced
posteriorly
AC joint irreducible on
exam
Occasionally associated
with SC dislocation
Type IV
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
Type V
Type VI
High energy variant
Result of
hyperabduction and
external rotation
Distal clavicle comes
to rest in subcoracoid
position
Summary
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
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
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)
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
What about Type III injuries?
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
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)
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
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
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 nonoperatively
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
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
McFarland MLB Survey Study 1997
American Journal of
Orthopedics, Nov 1997
Phillips et. al CORR 1998 Meta-analysis
Type III AC Injury
Pain absent or minimal
ROM normal/near normal
Strength normal /near normal
Subsequent surgery
OP
93%
86%
87%
59%
vs
NON-OP
95%
95%
91%
6%
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%
Types IV, V, IV
All require operative intervention
All stabilizers, static and dynamic are
injured
Treatment Old School
Not well tolerated, Dermal Complications
Surgical management
Fixation across AC joint
Fixation between coracoid and clavicle
Ligament reconstruction
Distal clavicle excision
Acromioclavicular Fixation
Pin fixation
Has been
abandoned since
reports of rare pin
migration

Heart, Lung,
Great vessels
Acromioclavicular fixation
Hook Plate
Only used for acute
injury
Requires
subsequent surgery
for removal
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
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
Ligament Reconstruction
orthoillustrated.com
Open and Arthroscopic techniques
Restore Anatomy
Anatomic Ligament
Reconstruction
Alternative technique is use of semitendinosus autograft 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
Biomechanical studies
Lee et al., 2003 – 11 cadaveric shoulders tensile tested to failure
comparing suture loop, CA transfer, and free tendon recon


Reconstructions found to have failure strengths as strong as those of
native CC ligaments
CA transfer was the weakest construct, and shows that greatest
elongation at failure
Concluded tendon graft reconstruction to be an alternative to CA lig
transfer possibly providing a permanent biologic reconstruction
Given its biomechanical properties similar to native CC ligaments,
reconstruction with tendon graft may allow for shorter post op
immobilization and accelerated rehab program
Biomechanical studies
Mazzocca et al, 2006, studied 42 cadaveric specimens
comparing stability of 3 AC joint reconstruction
techniques


Anatomic CC reconstruction with tendon graft provided ant, post,
and superior stability similar to intact state
Modified Weaver-Dunn had significantly greater laxity compared
to anatomic CC recon and arthroscopic reconstruction
Concluded that anatomic reconstruction with free tendon
graft may provide stronger, more permanent biologic
solution for AC joint dislocation
Newer proposed techniques
Grutter and Petersen 2005
AJSM (Cadaveric study)
Anatomic Reconstruction using
FCR graft to reconstruct CC
and superior AC ligament
Similar strength as native AC
joint in coronal plane
Newer Proposed Techniques
Freedman et al AJSM 2010
(Cadaveric study)
Intramedullary AC reconstruction with 5 cm
semitendinosus graft and fibertape
AP translation

Intact: 2.34 - 7.86 mm

Recon: 1.20 - 2.95 mm
Superior/Inferior translation

Intact: 2.56 - 6.16 mm

Recon: 2.42 - 4.57 mm
Did not reproduce similar stiffness, load to
failure, and energy absorption as intact AC
complex
Newer proposed techniques
AJSM 2010
Improved horizontal stability with
addition of intramedullary AC
ligament reconstruction.
-50% less AP translation
No difference in:
- Superior/inferior translation
- Load to failure
Complications
Non operative




Pain
Post traumatic arthritis/osteolysis
Possible neurologic injury
Possible strength deficit
Surgical





Same as above plus…
Clavicle or coracoid fracture
Loss of reduction
Pneumothorax
Neurovascular injury
Summary
Type I, II



restricted activity initially
Analgesic, Injection
Rehabilitation
Type III



Controversial- trends toward initial non-operative
management
Late reconstruction if symptomatic
Optimal strategy has changed and alternated over
time
Type IV,V, VI

Repair/reconstruction
Case
HPI: 21 yo R HD male college student
presents to clinic after fell off bike over the
handle bars onto his R shoulder
Exam:



Ecchymosis, Gross deformity R AC joint
TTP distal clavicle and CC interspace
Distally NVI R upper extremity
Radiographs
Post op
Acute CC repair with Fiberwire Suture Loops
References
•
Bannister, G, Wallace, W, Stableforth, P.G.: The Management f Acute Acromioclavicular Dislocation. JBJS(Br) 1989; 71-B:848 -50
•
Galpin, R, Hawkins, R, Grainger, R: A Comparative Analysis of Operative Versus Nonoperative Treatment of Grade III Acromioclavicular Separations. CORR
1985;193:150-155
•
Glick, J, Milburn, L, Haggerty, J, et al: Dislocated acromioclavicular joint. Follow-up study of 35 unreduced acromioclavicular dislocations. Am J Sports Med 1977;5: 264270
•
Lemos, M: The Evaluation and Treatment of the Injured Acromioclavicular Joint in Athletes. Am J Sports Med 1998;26:137-144
•
Lee, S, Nicholas, S, Akizui, K, et al: Reconstruction of the Coracoclavicular Ligaments with Tendon Grafts. Am J Sports Med 2003;31:648-654
•
Mazzocca, A, Santangelo, S, Johnson, S, et al: A Biomechanical Evaluation of an Anatomical Coracoclavicular Ligament Reconstruction. Am J Sports Med 2006;34:236246
•
McFarland, EG, Blivin, SJ, Doehring, CB, et al: Treatment of Grade III Acromioclavicular Separations in Professional Throwing Athletes. Am J Orthop 1997;11:771-774
•
Simovitch, R, Sander, B, Lavery, K, et al: Acromioclavicular Joint Injuries: Diagnosis and Management. JAAOS 2009;17:207-219
•
Wojtys, E, Nelson, G: Conservative Treatment of Grade III Acromioclavicular Dislocations. CORR 1991;268:112-119
•
Galatz, L, Williams, G: Acromioclavicular Joint Injuries. Rockwood and Green’s Fractures in Adults, 5th ed. 2002;1210-1244
•
Mazzocca, A. Arciero , R . Evaluation and Treatment of Acromioclavicular Joint Injuries. Am J Sports Med 2007 35: 316
•
Grutter, P. Petersen, S. Anatomical Acromioclavicular Ligament Reconstruction. Am J Sports Med 2005 33: 1723
•
Mikek, M. Long-Term Shoulder Function After Type I and II Acromioclavicular Joint Disruption. Am J Sports Med 2008 36: 2147
•
Schlegel, T et al. A Prospective Evaluation of Untreated Acute Grade III Acromioclavicular Separations. Am J Sports Med 2001 29: 699
•
Gonzalez-Lomas, G et al. Intramedullary Acromioclavicular Ligament Reconstruction Strengthens Isolated Coracoclavicular Ligament Reconstruction in Acromioclavicular
Dislocations. Am J Sports Med 2010 38: 2113
•
Tauber, M, et al. Dynamic Radiologic Evaluation of Horizontal Instability in Acute Acromioclavicular Joint Dislocations. Am J Sports Med 2010 38: 1188
•
Mouhsine E, Garofalo R, Crevoisier X, Farron A. Grade I and II acromioclavicular dislocations: results of conservative treatment. J Shoulder Elbow Surg. 2003;12:599-602
•
Phillips A, Smart C, Groom A. Acromioclavicular dislocation. Clin Orthop Relat Res. 1998;353:10-17
•
Weinstein, D et al Surgical Treatment of complete acromioclavicular dislocations. AJSM 1995 23: 324-330
•
•
Kibler, B. AAOS OKU Sports Medicine 4 2009
Google Images
Thank You
• Questions?