Everyone who works in sports medicine knows it; female athletes tear their anterior cruciate ligaments (ACL) more often than do their male counterparts. In fact studies have shown that women are 8 times more likely to sustain a rupture of the ACL than men. With the cost of surgical reconstruction and rehabilitation over $25,000 researchers are trying to find ways to decrease the frequency of these injuries.
In order to develop an injury prevention program, it is necessary to understand why females are more likely to injure their ACL. Many factors have been proposed including a narrower femoral notch, increased laxity during phases of the menstrual cycle, a wider pelvis and larger "Q" angle, greater hip varus, knee valgus and foot pronation.
Obviously, these are structural issues and can't be addressed through training, however some other factors have been observed that are addressable. These include a smaller hamstring to quadriceps strength ratio, poor recruitment of the hamstrings during landing, inappropriate jumping mechanics and weak hip abductors.
Now we have the advantage of knowing that training programs to address these issues work, they actually reduce the incidence of ACL injuries. At the Cincinnati Sports Medicine Research and Human Performance Laboratory, Tim Hewett, PhD has designed a prevention program to teach proper landing techniques.
In a recent study Dr. Hewett reported two non-contact ACL tears among 366 women who participated in a six-week training program. In the non-training group of 463 women, there were 10 ACL injuries.
Soccer players have been a focus of researchers. Bert Mandelbaum, MD of the Santa Monica Orthopedic and Sports Medicine Research Foundation designed a program that was implemented as part of the warm-up before practice.
Over two years his girls participating in the training (1,885) sustained 6 ACL injuries while the control group (2,994) sustained 67 ACL injuries.
ACL Injury Prevention Program
One of the keys to a successful ACL injury prevention program is the ability to teach jumping and landing mechanics. The athlete needs to learn to land with weight distributed along the midfoot. They should not land on the toes or ball of the foot. With the weight more evenly distributed, the athlete can take advantage of the elasticity of the muscles and ligaments.
Vern Gambetta has indicated that an easy way to teach this is to practice landing barefoot on a forgiving surface. He recommends a verbal cue of a "quiet landing" rather than a "soft landing". He feels that encouraging a soft landing leads to a mushy, weak landing, where a quiet landing implies strength and control.
My next article will address the strength training component of an ACL injury prevention program, followed by part 3 that will illustrate jump training and part 4 that will cover in-season training.
Gambetta, Vern. Bettering The Odds. Training and Conditioning. July/August 2003.
Vescovi, J & Brown, T. Decelerating Injuries. Training and Conditioning. March 2002
About The Author
Eric Wheeler, MSPT, MPE, CSCS
Eric is a staff physical therapist at Cape Cod Rehabilitation, an out-patient orthopedic and sports physical therapy clinic with offices in Mashpee, Hyannis and Osterville, Massachusetts. He is also the sports medicine consultant to the Cape Cod Crusaders of the PDL soccer league.
A graduate of Springfield College he holds Masters Degrees in Physical Therapy and Physical Education, is a Certified Strength and Conditioning Specialist (NSCA) and a member of the National Academy of Sports Medicine. He can be reached at firstname.lastname@example.org.
Note: This is part one, click here for part two.