70% of athletes that present with a swollen knee have a torn ACL. Learn about Anterior Cruciate Ligament (ACL) injuries, treatment and prevention.

1. Anterior Cruciate Ligament
(ACL) Injuries:
Treatment & Prevention
David A. Abrutyn, M.D.
Sports Medicine
Shoulder & Knee Surgery

2. What Are We Talking About?

3. Anatomy
• Two Bundles:

Anteromedial (AM)
• Proximal/Posterior
• Anterior/Medial

Posterolateral (PL)

4. Significance

5. What Does the ACL Do?
• Functions to resist anterior
translation of the tibia on
the femur
– AM bundle
– Provides 85% of resistance to the
anterior drawer in 90o of flexion
• Resists tibial rotation
– PL bundle
• Helps provide varusvalgus stability when the
knee is in full extension

6. Why Are We Talking About It?

7. Background
• Second most commonly
injured ligament in the knee
• Estimated to occur in 1 in
3000 people in the U.S.
• Resulting in an estimated
100,000 reconstructions a
year
• 6th most common orthopaedic
procedure performed in the
U.S.

8. Gender Differences
• Female:Male Ratio 9:1


Collegiate Basketball 3.5x
Soccer 2.67x
• Recreational Alpine
Skiers

9. How Does It Happen?
• The majority of ACL injuries
occur from non-contact injuries
(70%)
– Pivot shift injury
– Individual decelerates
– Try to change
directions abruptly or
lands from a jump
– Females are 6-9 times
more likely to suffer an ACL
tear

10. What Causes ACL tears?
• Position of body during
landing, cutting, pivoting
Hips & Knees are straight
Landing on flat feet
Puts ACL at risk
• Versus
Hips & Knees bent
Landing on toes
Risk of ACL injury
minimized
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11. Risk Factors
• Muscle Imbalance
Hamstring/Quadriceps
Poor Hamstring Strength
• Hamstring protect
ACL
• Quadriceps
stretch/stress ACL
• Slow activation of
hamstring with
pivot/landing



12. Risk Factors
• Anatomic Factors

13. Risk Factors
• Environmental Factors

14. Risk Factors
• Hormonal Factors


ACL estrogen receptors
Estrogen
• Ligament looseness
• Increased in girls vs. boys
• Increased @ specific times during menstrual
cycle

Studies VERY inconsistent

15. Goals of ACL Reconstruction
• Provide stable & painfree knee under
physiologic loads
• Expedient return to
previous level of function
• Help prevent future injury
to meniscus & cartilage
• Prevent future
degenerative arthritis?

16. Are We Successful?
• Risk of re-tearing after ACL
reconstruction 6%
Range 3-30%
• Risk of re-tearing opposite
side 12%
• 50% return to competing at
same level
80% return to competitive
level



17. What is the Problem?
• Surgical Technique
Tunnel position
Fixation
Graft choice
• Rehab program
• Patient factors
Concomitant injuries
Not all ACL injuries are the same
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18. Principles ACL Reconstruction
• Anatomic
Approach

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
Restore knee
mechanics
Improves
Rotatory stability
Tunnels drilled
independently
• Sadoghi P et al
Arthroscopy 2011

19. Trans-Tibial Approach

20. Rehab Principles
• Immediate Post-Op



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Bracing
Cold Modalities
Quad isometrics
SLR
Heel Slides
• Week 1-2
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Minimal Swelling
Increase ROM (0-90)
Closed Kinetic Chain Activities

21. Rehab Principles
• 4 weeks
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ROM (0-120)
Increase Strength
Cardiovascular training
Aquatic Therapy
• Weeks 5-12
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Increase flexibility
Continue Strengthening
Neuromuscular control
Running

22. Return To Play Criteria
• Increase strength, power and endurance

90% uninvolved leg
• Increase running & cutting to meet
demands of individual sport
• Increase cardiovascular demands
• Progress to partial or full sport activities

6-9 months
• RTP < 7 months--15.3% retear
• RTP > 7 months--5.2%
– Laboute et al, Ann Phys Med Rehab 2010

23. We Can’t Rush Biology
• ACL Graft


Undergoes necrosis &
remodeling
Revascularizes @ 8-10 weeks
• Completed in 16 weeks

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Cellular Proliferation 4-8
weeks
Graft firmly attach to bone @
8 weeks
1 year before graft appears
histologically normal

24. Can We Prevent It?
• Biomechanical factors
critical
• Neuromuscular/Proprioce
ptive programs
• Dramatic reduction in ACL
tears
• Plyometric/jump training

Balance drills

25. Principles
• Emphasize proper
jump/landing techniques
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Land on balls of feet
Soft landing
Toe-to-heel rocking of the foot
• Decrease ground reactive
forces
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Knee flexed
Knee forward
Discourage inward buckling
Chest over knees

26. Studies
• PEP program
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80% reduction over 2 years in girls playing
soccer ages 14-18
Mandelbaum
aclprevent.com
• Balance Drills

Carraffa
• Jumping Drills
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Hewett

28. Summary
•
•
•
•
ACL tears continues to increase
Not all ACL tears are the same
Anatomic Reconstruction is important
Return to play
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Need to be realistic
Appropriate expectations
• ACL Prevention
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Neuromuscular training is effective
aclprevent.com

29. Questions?