The following is a summary of the presentation given by Dr. Richard Hinton at the 2013 US Lacrosse Sports Medicine Symposium in Philadelphia.
 

"This is a life altering injury."

Those were the sobering words that highlighted the presentation about ACL (anterior cruciate ligament) knee injuries by Dr. Richard Hinton during the 2013 US Lacrosse Sports Medicine Symposium.

	Dr. Richard Hinton

"Everybody is focused on concussion problems these days. That’s the hot-button issue," said Hinton, director of MedStar Sports Medicine in Baltimore and team physician for the U.S. Women’s National Lacrosse Team. "But ACL injuries are in fact the leading cause of game and practice missed time by lacrosse athletes. Period."

Among the statistics that Hinton shared during his presentation were that only 5-15% of the grafts performed in ACL reconstruction fail (tear in half), but still less than 60% of all athletes who sustain an ACL injury return to the same level of play following the injury.

"A more intelligent approach to research and treatment of the ACL is desperately needed," Hinton said. "We have a problem here that we don’t have a great answer for."

Hinton explained that the knee is a very complex joint and is the primary stabilizer for sports activity, but that it is designed for efficient, upright, bi-pedal gait, moderate speed, and long distance running, not the jump, cut, twist and turn sports in which humans choose to participate.

"The knee has very complex biomechanics and there are any number of places where the knee joint can fail when it is overstressed," Hinton said. "We must accept the risks that come with jump, cut, twist, turn sports."

In regards to risk assessment, Hinton explained that most of the current focus is on the athlete and his or her personal characteristics, rather than on the environment. The days of evaluating ACL risk based on artificial playing surfaces vs. natural grass fields, for example, are long past.

"We’re looking at what the athlete brings to the table, and more importantly, what, of those things, can we modify so that they don’t have a recurrence of the same injury," Hinton said.

Hinton cited landing techniques as an example, noting that athletes must be trained to "land soft and land stacked." Proper mechanics and posture allow the body to absorb energy so that it is not being transmitted to the ACL.

Hinton acknowledged that females are at higher risk than males for ACL injuries in some sports. Statistics show that female athletes in the NCAA sports of soccer and basketball have ACL injury rates 3-4 times higher than that of their male counterparts, however, occurrences of ACL injuries in women’s lacrosse are not significantly higher than in men’s lacrosse.

All told, there are approximately 200,000 ACL injuries and reconstructions in the U.S. every year, and $3 billion is spent on direct and indirect medical costs associated with these injuries. Hinton noted that in the early 1980s, only one-third of those that suffered ACL tears opted for surgery. Others simply modified their activities and had few ongoing symptoms. Conversely, almost 100% of today’s ACL tears result in surgery.

"That’s not how it has to be," Hinton said. "Some low-demand people can do very well without an ACL."

Hinton's complete presentation and notes from all the other presentations during the Symposium can be accessed here.