The Female Knee Creates the MVP (Most Vulnerable Player)
Anastasia N. Fischer, MD Nationwide Childrens Hospital Dept. of
Sports Medicine Slide 2 What well cover today ACL tears are a
relatively common injury in female sports Girls are more prone to
ACL tears than boys Why? What can we do about it? Slide 3 ACL
Injuries in Girls 38,000 estimated female ACL injuries each year
Estimated 2,200 at the collegiate level Estimated 2,200 at the
collegiate level May be 4 times as high at HS level (8000-9000!!)
May be 4 times as high at HS level (8000-9000!!) Slide 4 ACL
Injuries in Girls Increased Participation in sports (Title IX)
Female basketball players are 2x more likely to suffer an ACL tear
than their male counterparts Female basketball players are 2x more
likely to suffer an ACL tear than their male counterparts Female
soccer players are 4x more likely to suffer an ACL tear than their
male counterparts Female soccer players are 4x more likely to
suffer an ACL tear than their male counterparts Slide 5 Why?
Theories To Explain Gender Differences Anatomical Differences
Biomechanical Factors Hormonal Influences Neuromuscular Differences
Slide 6 Anatomic Differences Women tend to have a more knock-kneed
leg alignment The femoral notch, in women tends to be narrower
Slide 7 Biomechanical Differences Compared with men, women: Have
less muscle mass Have less muscle mass Are slower at the rate of
muscle force development (ms) Are slower at the rate of muscle
force development (ms) Have a stronger, quicker reacting quadriceps
relative to hamstrings Have a stronger, quicker reacting quadriceps
relative to hamstrings Tend to be more upright when landing Tend to
be more upright when landing Tend to be quad dominant Tend to be
quad dominant Slide 8 Hormonal Influences? Increased risk of ACL
tears during ovulatory phase of menstrual cycle Decreased risk of
ACL tear during follicular phase of menstrual cycle Recent studies
are conflicting, these results are not widely supported Slide 9
Neuromuscular Differences Ligament Dominance Knee ligaments rather
than knee muscles absorb the landing forces during sports maneuvers
Knee ligaments rather than knee muscles absorb the landing forces
during sports maneuvers Quadriceps Dominance Quads react more
quickly to forces than the hamstrings Quads react more quickly to
forces than the hamstrings Leg Dominance The non-dominant knee is
at greater risk because its weaker The non-dominant knee is at
greater risk because its weaker Slide 10 What does this all boil
down to? 4 out of 5 ACL injuries occur from a non- contact
mechanism - very often during deceleration activities, (i.e.
landing from a jump or planting and cutting) and are due to being
in the position of no return Slide 11 Biomechanics Slide 12
Biomechanics Slide 13 How Can The Incidence of ACL Injuries Be
Reduced? ACL injury prevention programs have demonstrated a
reduction in the rate of ACL injuries in 14-18 year old girls by
74-83%!! Helping to change the position of the knee when landing or
cutting and pivoting Helping to change the position of the knee
when landing or cutting and pivoting Decreasing landing forces on
the knee when landing from a jump Decreasing landing forces on the
knee when landing from a jump Slide 14 Strategies to Avoid Injury
Avoid vulnerable positions Avoid vulnerable positions Increase
flexibility Increase flexibility Increase strength Increase
strength Increase balance through agility training Increase balance
through agility training Include sports specific exercises into the
training program Include sports specific exercises into the
training program Slide 15 Injury Prevention Protocol A 3 phase
program done three days / week beginning six to eight weeks prior
to the season Technique phase: teach proper jump technique - Learn
to stick and hold landings Technique phase: teach proper jump
technique - Learn to stick and hold landings Fundamental phase:
continue to build strength, power and agility Fundamental phase:
continue to build strength, power and agility Performance phase:
focus on increasing maximum vertical jump height and sports
specific training Performance phase: focus on increasing maximum
vertical jump height and sports specific training Slide 16
Technique Phase At the start proper landing form must be reinforced
The athletes should be taught to land on the balls of the feet with
the knees flexed and the chest over the knees Verbal cues: Sit back
Land soft toes-> heels Legs are shock absorbers (instant recoil
for next jump) Slide 17 Technique Phase Focus in this phase must be
on perfecting the technique of each exercise Athletes need
immediate feedback Wall jumps Wall jumps Squat jumps Squat jumps
Broad jump and hold Broad jump and hold Slide 18 Fundamental Phase
Training should focus on strength and balance Exercises should
include dynamic, multi-planar, sport- specific movements that are a
challenge to the proprioceptive system Slide 19 Fundamental Phase
Strength exercises must also include the core Critical for body
control Critical for body control Progression must be slow and
methodical with enough recovery time Balance activities should be
progressive Single leg passing (bounce -> chest -> OH) Single
leg passing (bounce -> chest -> OH) Single leg woodchops
Single leg woodchops Multidirectional lunges Multidirectional
lunges Single leg jump and hold Single leg jump and hold Power
skipping Power skipping Slide 20 Performance Phase Practical
application: Training skills should expose the athlete to movement
patterns that generate greater dynamic knee control Training skills
should expose the athlete to movement patterns that generate
greater dynamic knee control Agility drills should be progressed
when the athletes can maintain good static body control Agility
drills should be progressed when the athletes can maintain good
static body control Slide 21 Performance Phase Exercises should
progress from previous phases and should now focus on power and
agility Power drills include advanced plyometrics and explosive
movements 180 Deg jumps 180 Deg jumps Barrier hops Barrier hops
Scissor jumps Scissor jumps Power skipping > maximize height
Power skipping > maximize height Box drop jumps > plant and
turn Box drop jumps > plant and turn Medicine ball vertical
throws Medicine ball vertical throws Slide 22 Injury Prevention
Protocol Optimally, after the training program, the program should
be performed at least 2-3 times per week during the season Program
consists of a warm-up, stretching, strengthening, plyometrics, and
sport specific agilities Program consists of a warm-up, stretching,
strengthening, plyometrics, and sport specific agilities The
coaches and athletic trainers need to emphasize correct posture,
straight up and down jumps without excessive side-to-side movement,
and reinforce soft landings The coaches and athletic trainers need
to emphasize correct posture, straight up and down jumps without
excessive side-to-side movement, and reinforce soft landings Slide
23 Preventative Training Programs Nationwide Childrens Sports
Medicines Personal Best Injury Prevention Programs ACL Bootcamp ACL
Bootcamp Shoulder Stability/Throwing Program Shoulder
Stability/Throwing Program LEAPS and BOUNDS LEAPS and BOUNDS Age
appropriate specific to their developmental level Sport specific
Basketball Basketball Soccer Soccer Baseball/Softball
Baseball/Softball Volleyball Volleyball Slide 24 Conclusion The
research and development of training programs to prevent ACL
injuries is evolving rapidly More attention needs to be placed on
implementing these programs to younger athletes during their
developmental years Slide 25 References Gilchrist J, etal. A
Randomized Controlled Trial to Prevent NoncontactAnterior Cruciate
Ligament Injury in Female Collegiate Soccer Players. Am J Sports
Med. 2008;36(8):1476-1483. Meyer GD, Ford KR, Hewett TE. Rationale
and Clinical techniques for Anterior Cruciate Ligament Injury
Prevention Among Female Athletes. Journal of Athletic Training.
2004;39:352-363. Mandelbaum BR, Silvers HJ, et al. Effectiveness of
a Neuromuscular and Proprioceptive Training Program in Preventing
Anterior Cruciate Ligament Injuries on Female Athletes. Am J Sports
Med. 2005;33:1003-1010. Olsen OE, Myklebust, et al. Exercises to
Prevent Lower Limb Injuries in Youth Sports: Cluster Randomized
Controlled Trial. British Medical Journal. 2005;330:449-452.
