How to spot warning signs of ACL injuries
Updated On: Jun 04 2013 03:53:00 PM CDT
COLUMBUS, Ohio – From professional athletes who lack proper conditioning because of a lockout to high-school girls who are more prone to injury, specific groups are statistically more likely to injure their anterior cruciate ligaments (ACL) while playing sports. The Ohio State University Wexner Medical Center is helping to identify and prevent injury for athletes most susceptible to ACL injuries.
Dr. Timothy Hewett, director of research at Ohio State University Sports Medicine, predicted in 2011 that NBA players would have 2-4 times higher rate of ACL injury after the lockout, and was correct in his prediction, with 3-4 times more ACL injuries in the NBA this year than usual.
“When training is delayed because of negotiations, and conditioning time is compromised, we risk our athletes becoming more seriously injured down the road,” said Hewett.
Hewett was recently invited to speak at the 2013 NBA Physician's meeting about how to prevent further ACL injuries in professional athletes, and will continue to work with their athletic trainers and strength coaches to focus on prevention techniques.
Using high-tech, infrared cameras and a gym floor tiled with motion-activated sensors, Hewett and other researchers at Ohio State’s Sports Medicine put athletes through various tests to track and animate their bodies using a 3-D computer program. Researchers analyze everything from an athlete’s body structure to their pattern of movement to predict how likely they are to injure their ACLs.
Once researchers identify these high-risk patients, they develop personalized exercise programs to strengthen an athlete, or help them correct their form in order to avoid injury.
“We use neuromuscular training, which teaches greater core control, better hip and knee control, and we do that in very challenging, sports-like environments to mimic conditions from the soccer field to the basketball court,” said Hewett.
Athletic trainers are teaching the same techniques to professional athletes as to high school girls and other at-risk athletes.
“We used to think these types of injuries were a result of body type or simply couldn’t be helped,” said Hewett. “But by teaching athletes to move differently while they are mimicking then playing their sports, we can prevent ACL injuries in groups with disparities.”
It was previously thought that females had a higher risk for ACL injury because of genetics or hormones, but Hewett says the way they control their core muscles, hips and knee joints causes the increased relative risk for injury.
“For high-school girls who are 4 to 10 times more likely to injure their ACLs than boys, you can actually reduce relative risk in women and girls to equal to that of men and boys,” said Hewett. “We have shown reductions in relative risk in the range of 60 to 65 percent, which is enormous.”
In this case, relative risk is the ratio of the chance of an injury developing among female athletes who complete the personalized exercise program compared to those who don’t, Hewett said.
“We make our female athletes aware of their movement and teach them to square up their knees properly to keep them from falling in,” sad Hewett. “We also measure their quadricep-hamstring strength. If their hamstrings are 50 percent or less as strong as their quadriceps, that means the back of their thighs are less than half the strength of the front and the risk for injury is high. Through our personalized training program, we can start rebalancing this strength.”
Researchers now know enough about ACL injuries that identifying those at risk can be done in a high-tech laboratory or at home. To determine if a child might be at risk, have her drop down off a foot-tall box and then immediately go into a high vertical jump. If right before she lands, her knees go together for half of her landing or more, she may have a higher-risk for injury.
Hewett says core strength can be determined using a simple exercise with an “X” of tape on the floor. The athlete hops on one foot between the four quadrants, counting the number of touchdowns on the right versus the left foot for 30 second. If there is a lot of using only one foot, the athletes needs to work on a more symmetric distribution of core strength to help prevent ACL injury.
“When a woman has torn one ACL, her relative risk of tearing it again is up to 16 times a person who has not torn their ACL,” said Hewett. “Once a female tears her ACL, not only does she have up to a year loss of the physical activity and benefit of her sport, but she also has between a 50 and 100 percent chance of developing osteoarthritis, which is a disabling knee condition. In a couple decades, that could mean a full knee replacement, which we want to avoid at all costs.”
Women basketball players have the highest sex-disparity relative risk and soccer has the most ACL injuries overall. Sports like skiing, handball and volleyball also put girls at risk for ACL injuries, according to Hewett.
“There are more than 120,000 ACL injuries a year in the United States, but we have the potential to reduce that by more than half, and prevent further even more serious injuries, which is key,” said Hewett.
Distributed by Internet Broadcasting. This material may not be published, broadcast, rewritten or redistributed.