Objectives
  1. Brief understanding of prevalence and risks 
     of ACL injuries
  2. Understand knee mechanics and importance 
     in  protecting the ACL
  3. Familiar with the components of ACL 
     prevention program 
        What is the ACL anyway?
  ACL – anterior    1 of 4 ligaments in 
   cruciate ligament   the knee joint
                     Provide stability by 
                       limiting the tibia 
                       (lower leg bone) from 
                       moving forward in 
                       relation to the femur 
                       (upper leg bone)
                     Limits rotation of the 
                       knee joint
                  ACL injuries/tears
   
     Contact vs. non-contact
      ~80% non-contact (soccer, basketball, skiing, etc.)
      ~20% contact (football, ice hockey)
   
     Non-contact – usually with landing, rapidly 
     stopping, cutting or change in direction
      Altered biomechanical and neuromuscular patterns
   
     Female athletes have 3.5 x risk of non-contact 
     injury compared to males
                              Figure 1b. Pivot shift injury.
             Sanders T G et al. Radiographics 2000;20:S135-S151
 ©2000 by Radiological Society of North America
            Prevalence of ACL injury
   
     Roughly 250,000 ACL Tears per year in the 
     U.S. 
       $20,000+ per reconstruction + rehabilitation
   
     $5 billion annual cost 
   
     6-12 months away from sport 
      High rate of re-injury upon return