One of the major problems facing female athletes is the risk of tearing their anterior cruciate ligament. Non-contact ALC injuries occur in women at a rate 4-6 times that of males. In addition to the personal costs, the financial costs of surgery and rehabilitation have been conservatively estimated at $1.7 billion annually. The exact reasons why women are so much more susceptible to ACL injuries than are men are still being debated. However, one issue that is clear is that something needs to be done to lower the risk of injury. One solution is the development of various neuromuscular training programs designed to prevent ACL injuries. In general, these programs use strengthening, plyometric, flexibility and balance exercises to enhance knee stability. But, do they really work? Do they actually reduce the risk of injuries in women?
A group of Korean researchers recently addressed these questions. To do this, they examined all of the available research studies involving women, ACL injuries and ACL injury prevention programs. Using these studies, this they performed a meta-analysis of the results. A meta-analysis is a statistical tool whereby the results of many studies are “pooled” and analyzed simultaneously. The goal is to come up with a “consensus” result. This process provides a more comprehensive look at whether or not these programs are effective in lowering the incidence of ACL injury.
Seven key studies were analyzed. All were similar in that they used young female subjects. Some subjects were under the age of 18 while a few studies used college-aged girls. In all, more than 11,000 subjects were included in the seven studies. The seven studies also used what is termed a “randomized control trial”. This means that each study compared a treatment group (received ACL injury prevention training) to a control group (received no prevention training). Also, the subjects were randomly assigned to one of the two groups.
The researchers found that the use of neuromuscular training was very effective in preventing ACL injuries in female athletes. The meta-analysis revealed that the neuromuscular training programs reduced the odds of suffering an ACL injury by 60%. These programs were more effective in young athletes. In adolescents, the odds of injury were cut by 73%.
The researchers also found that using a neuromuscular training both before and during the season was more effective than using the program only during pre- or in-season. The intensity of the program seemed to be an important factor. Programs conducted at practice and supervised by a coach were more effective than a home-based program. Lastly, plyometrics and strength training seems to be a bit more important than balance training. It seems that starting early in a players career may be more effective that beginning later.
Back to the original question; does ACL injury prevention really work? Based on this paper, the answer is a definitive yes. By including neuromuscular training as a part of both pre-season and in-season practice, the risk of suffering an ACL injury can be substantially reduced.
It is important to point out that this study shows that training can reduce the risk of injury. It does not indicate that this type of training will prevent injuries from occurring. Some injuries will occur despite the best training efforts. However, lowing risk will reduce the overall number of injuries that occur on a single team or within an individual club. Thus, improving the odds of avoiding ACL injuries will help a large number of players stay healthy and increase the chances of a successful season.
Yoo JH, Lim BO, Ha M, Lee SW, Oh SJ, Lee YS, Kim JG (2009) A meta-analysis of the effect of neuromuscular training on the prevention of the anterior cruciate ligament injury in female athletes. Knee Surgery, Sports Traumatology and Arthroscopy, DOI: 10.1007/s00167-009-0901-2.
For more info on neuromuscular training programs, follow these links:
Santa Monica Orthopedic and Sports Medicine Group PEP Program