By Staff
Coaching Management, 9.9, December 2001, http://www.momentummedia.com/articles/cm/cm0909/bbacl.htm
A recent study linking hormones to anterior cruciate ligament (ACL) injuries has been getting a lot of attention. The research showed that women may be at greater risk of tearing their ACL (perhaps the most significant ligament in the knee) during the ovulatory phase of their menstrual cycle. The study won the prestigious O'Donoghue Sports Injury Research Award when it was presented at the annual meeting of the American Orthopaedic Society for Sports Medicine (AOSSM) in June.
The significance of the findings is unclear, however. Just a few days before the research was presented, the results of another study were given at the National Athletic Trainers' Association meeting that also linked hormones to ACL injuries. But those researchers found that women were more prone to the injury at a different time in their cycle. These two studies have fueled a long-standing debate over how large a factor hormones play in ACL injuries--and what to do about it.
It has been known for years that women are much more likely than men to tear their ACLs--a devastating injury that is becoming all too common among volleyball players. Researchers have been trying to explain the discrepancies between the men's and women's rates, with three theories gaining prominence: anatomical differences, neuromuscular differences, and hormonal fluctuation differences.
The study presented at the AOSSM meeting was led by Dr. Edward Wojtys, Medical Director of the University of Michigan's MedSports Program. He and his colleagues found that women have a significantly greater chance of ACL injury during the ovulatory phase of their menstrual cycle (days 10 to 14, when estrogen levels peak) than during other times of their cycle. The study also found that women not taking oral contraceptives had a greater number of ACL injuries than those on birth control pills.
The other recent study, headed by Dr. James Slauterbeck, Vice Chairman of Orthopedics at Texas Tech Medical Center and a Team Physician for the Red Raiders, looked at injuries during two phases, the follicular (first half) and luteal (second half) phases of the menstrual cycle. He found most injuries occurred during the final days of the luteal phase and the first days of the follicular phase, around the time of menses.
The theory that hormones may play a role in increasing a woman's risk of ACL injury surfaced more than a decade ago. Both studies presented this summer, however, used much more reliable methods of matching a woman's place in her menstrual cycle to the time of her injury than those used in past studies, and thus have garnered the attention of team physicians and athletic trainers.
But experts emphasize that such studies are only a first step toward developing any possible new strategies for preventing the injury. There are still more questions than answers at this point, and female athletes should be reassured that proper training is still the best bet for prevention.
"Based on the knowledge we have, it would be a mistake to say that female athletes are more or less susceptible to injury at particular points in their cycle, or that just because their ligaments are more lax, they are more at-risk or less at-risk of injury," says Dr. Sandra Shultz, Assistant Professor and Interim Coordinator of Graduate Programs in Athletic Training and Sports Medicine at the University of Virginia. "So, I don't think we can make any recommendations to athletes based on their menstrual cycles, hormones, or birth control pills related to ACL injury."
Athletic trainers, researchers, and team physicians agree that the main thing to focus on at this point are those things that are known to benefit athletes. "I think what you have to focus on are factors that we can make a change in," says Shultz. "Studies show that doing some kind of preventative training program that works on landing, on cutting with good technique, and on hamstring strength does appear to lead to a reduction in injury rate."
Dr. Carol Otis, Primary Care Physician in Women's Sportsmedicine at the Kerlan-Jobe Clinic in Los Angeles and a former team physician for UCLA, agrees: "There are differences [between men and women] in landing and in hamstring and quad activation. So, the most important thing athletes can do is to work on their technique, particularly landing and taking off. They also need to make sure they have the proper footwear for the surfaces they're going to be playing on."
A more comprehensive article on this topic is running in the November issue of our sister publication for athletic trainers, Training & Conditioning. This and other articles on preventing ACL injuries can be found on our Web site, www.AthleticSearch.com, by typing "ACL" into the search field.