Download ACL INJURIES IN SOCCER

ACL INJURIES IN
SOCCER
Allis Kim, MD
Orthopedic Affiliates
Background
  250,000 ACL injuries/yr in USA
 50% are in athletes15-25 years old
 Require reconstructive ACL surgery
 6-9 month recovery
  80 - 90% return to previous level of
play
Overview
  Knee Anatomy
 Function ACL
  ACL injuries
 Mechanism
 Risk factors
 Prevention
Knee Anatomy
Ligaments
  MCL-medial collateral ligament
  LCL-lateral collateral ligament
  PCL-posterior cruciate ligament
  ACL-anterior cruciate ligament
Menisus
  Medial and lateral
Articular Cartilage
ACL: Function
  Keep tibia from sliding forward on the femur
ACL Tear
Mechanism
  Direct contact with another
player-30%
  Non-contact 70%
Mechanism: Contact
  Hit on outside of leg
  Twisting of knee
Mechanism: Non-Contact
  Deceleration & pivoting
  Landings
Mechanism: Non-contact
PIVOT
  Deceleration, planting foot, then change directions
  Causes twisting injury of knee (Pivot)
  Traction at shoe/playing surface interface
  One step stop
ACL
Mechanism: Non-Contact
LANDING
  Stiff Knee on landing
  Quad pulls tibia forward
Risk Factors
  Shoe surface interactions
  Uneven playing surfaces
  Biomechanical factors
  Female
  Anatomic
  Biomechanical
Risk Factors: Shoe surface
interactions
  Footwear
  High level of friction between shoes and playing
surface increases strain on the ACL
  Cleats on artificial turf have 45% higher strain on
ACL than cleats on grass
Risk Factor
  Uneven playing surface
  Unexpected foot position may change
muscle activation patterns
  Balance thrown off
Risk Factors
  Biomechanical
  Neuromuscular control
Complex interplay between the
neurologic system and the muscles that
cross the knee joint
  How you landing & pivoting
  Muscle imbalance
  Proprioception
  Sense of balance
Risk Factors
  Landing / Pivoting with only a little bend in the knee
  Places ACL in vulnerable position
  Additional torsion/twisting can → injury
Risk Factors
  Hamstring/Quadriceps imbalance
  Poor hamstring strength
  Hamstrings protect ACL
  Quads stretch/stress ACL
  Slow activation of hamstring muscles with
pivot / landing
Risk Factors: Females
  Female
  2-8 times the risk
  Anatomic
  Biomechanical
Female Gender
  Anatomy
  Smaller intercondylar notch
  ACL may get stretched
across bone and torn
  ACL thickness
  Hormonal risk factors
  Insufficient data
Female Gender
  Lower extremity alignment
  Increase hip angle
  Women are more knock kneed.
(Increase Q angle)
  Increase rotation of shin bone
  Excessive foot pronation (flat
foot)
  Increase laxity in ligaments
  Data not great
Risk Factors
  Female Gender: Biomechanical
  Land in a more upright position
  Boys lands with knees more bent
  Poor hamstring: quadriceps strength
  Activate hamstring more slowly
Prevention
  Bracing
  Shoewear
  Neuromuscular Training program
  Does it work?
Bracing
  Several studies
  Inconclusive results
  No change in muscle
activation patterns
  No ↓ ACL shown in any study
  Loads placed on brace during
play exceeds brace
  BUT, many athletes who have had
ACL surgery FEEL more stable in
brace
Prevention: shoe wear
  Shoes with lower ACL injury risk:
  Cleats flat, all the same size on forefoot
  Screw in cleats with 0.5 in ht/diameter cleats
  Pivot disk: 10-cm circular edge on sole of forefoot
  Flat shoes on artificial turf
  Balance of too much / too little traction
Prevention
  Neuromuscular Training Program
  Body control
  Increase strength, muscle activation
& endurance
  Change landing/pivoting patterns
Program Goals
  Emphasize proper jump/land
techniques
  Land on balls of feet
  Soft landing
  Toe-to-heel rocking of the foot
  Knees flexed & forward
  Discourage inward buckling of
  knees (knock-kneed landing)
  Chest over knees
  Stop over several steps instead of
one
  Improve hamstring strength and
activation
Program Goals
Proper landing
  Before Training
  After training
Performance Enhancement
  ↑ Vertical jump
  ↑ 10%
  ↑ Strength
  ↑ hamstring strength 44%
  ↑ Sprint speed
  Improved power endurance
Prevention
  Does it work?
  Division 1 Basketball players
  ↓ ACL injury rate by 89% over 2 years
  Soccer players
  1.15 ACL per team per year to 0.15 injury per
team (300 soccer players)
  1,263 volleyball, soccer & basketball athletes
  ↓rate by 3.6X
Summary
  ACL Injury
 Devastating injury
 Requires surgery & prolonged
rehabilitation
 Females and higher risk 2-8 times
  Prevent ACL injuries
 Proper shoewear
 Neuromuscular training
  Improves athletic
  performance
Questions?
Thank You