ACL stats

The anterior cruciate ligament, or ACL, is one of the most commonly injured ligaments in the knee.

About 150,000 ACL injuries occur each year.

Female athletes playing basketball or soccer are two to eight times more likely to suffer from an ACL injury.

ACL injuries account for an estimated $500 million in health care costs each year.

Research suggests that half of the patients with an ACL injury will develop degenerative knee osteoarthritis in 10 to 20 years.

Female athletes between the ages of 15 and 20 years old account for the largest number of ACL injuries. At the high school level, girls soccer has the most ACL injuries, followed by boys football, girls basketball, girls gymnastics, and boys and girls lacrosse.

Research demonstrates that specific types of physical training, such as strength training, core stability training and plyometrics, can reduce the risk of ACL injury as much as 72 percent, especially in young women. American Academy of Pediatrics encourages coaches and school sports programs to learn about the benefits of this kind of "neuromuscular" training.

SOURCES: American Academy of Pediatrics and American Orthopaedic Society of Sports Medicine.

Like so many ambitious teenage girls today, Lindsay Manning loves to play sports.

The Cane Bay High School senior who will be attending Clemson University in the fall has run cross-country and track and played basketball and volleyball.

But in December 2012, when Manning was a junior playing in the third game of the basketball season, she leaped to save a ball from going out of bounds, landed on her right leg and heard the dreaded "pop!"

She had torn the anterior cruciate ligament, or ACL, in her right knee.

"I had been taking a sports medicine class and immediately knew what happened," says Manning.

What ensued was a period of letting the swelling go down, doing some pre-surgery strengthening or "pre-hab" of her quadriceps and then, in mid-January, having surgery, and then nearly seven months of recovery.

Manning was cleared just in time to play volleyball and enjoyed full seasons of both volleyball and basketball, though she wore a brace on her knee. And while she does not plan to play varsity sports at Clemson, she does look forward to playing intramural sports in college and enjoying a lifetime of athletic activities.

Preventing injuries

Manning's case is far from unusual.

As more youth, especially girls, participate in organized sports, doctors are seeing increasing numbers of ACL tears, particularly in the high school sports of soccer, basketball, volleyball and gymnastics.

Dr. George Pappas, an orthopedic surgeon at South Carolina Sports Medicine & Orthopaedic Center in North Charleston, was the surgeon who performed Manning's surgery and suspects the increase in ACL injuries is "likely due to a combination of increased participation in high-demand sports at an earlier age as well as improved diagnosis of ACL injuries, including the more common use of MRI scans to identify tears."

The statistics are enough that the American Academy of Pediatrics recently came out with a new guide to prevent, diagnose and treat ACL injuries in young athletes. The report, "Anterior Cruciate Ligament Injuries: Diagnosis, Treatment, and Prevention," is published in this month's edition of the journal, "Pediatrics."

The report outlines the approach to treating ACL injuries, including less invasive surgical techniques that protect the developing growth plates in young athletes.

More importantly, the report recommends proven ways athletes can reduce their risk of injury in the first place. Research demonstrates that specific types of physical training can reduce the risk of ACL injury as much as 72 percent, especially in young women.

"Neuromuscular training programs strengthen lower extremity muscles, improve core stability, and teach athletes how to avoid unsafe knee positions," says Dr. Cynthia LaBella, lead author of the report and a member of the academy's Council on Sports Medicine and Fitness.

The academy recommends plyometric and strengthening exercises to reduce athletes' risks of being injured, and encourages coaches and school sports programs to learn about the benefits of this kind of neuromuscular training.

Girls vs. boys

Those preventive measures may be more important for girls. The report says female athletes between the ages of 15 and 20 years old account for the largest number of ACL injuries. At the high school level, girls soccer has the most ACL injuries, followed by boys football, girls basketball, girls gymnastics, and boys and girls lacrosse.

Timothy Hewett, co-author of the report, says the reason for that is that girls after puberty have a "machine motor mismatch," in which neuromuscular strength and coordination lags behind growth.

"In contrast, boys get even more powerful relative to their body size after their growth spurt. The good news is that we've shown that with neuromuscular training, we can boost the power of girls' neuromuscular engine, and reduce their risk of ACL injuries," says Hewitt.

Among high school and college athletes, females have two to six times higher ACL injury rates than males in similar sports. Compared with boys, girls are more likely to have surgery and less likely to return to sports after an ACL injury.

Pappas says risk factors that predispose girls to non-contact sport ACL injuries, which represent 70 percent of the injuries, include "weaker hamstrings, higher-risk mechanics such as a tendency to land with a straighter knee, joint laxity and tendency to be more knock-kneed due to a wider pelvis."

"So it's reasonable to conclude that programs that improve strength and mechanics, such as landing on a flexed knee, rounding turns and taking multistep deceleration, may be more beneficial to girls. Studies, however, have shown that these programs are certainly beneficial for male athletes as well," says Pappas.

Pappas stresses that even though the rate of ACL injury is higher in girls than in boys, the overall number of ACL injuries is still higher in boys.

Important step

Cane Bay High's athletic trainer Laren "Doc" Siefken says the recommendations for strength and balance training to prevent knee injuries is not new for trainers but will hopefully convince athletes, their parents and coaches of the need for it.

Siefken adds that it also underscores the need for female athletes to have proper training, as well as time in the weight room, often dominated by football players.

Both he and Pappas applauded the report and new guidelines, particularly the urging of using plyometric and strength training to prevent injury in the first place.

"This training strengthens lower extremity muscles, improves core stability, and teaches young athletes how to avoid unsafe knee positions," says Pappas.

"This is especially critical because ACL injuries increase the risk of developing knee osteoarthritis down the road, and we have not been able to demonstrate that surgical intervention (ACL reconstruction) decreases this risk of developing arthritis."

Pappas says that preventing an ACL injury in a high school athlete will help them avoid the long-term consequences of developing a painful, arthritic knee in their 20s or 30s.

He adds that athletes with an ACL injury are up to 10 times more like to develop degenerative arthritis, regardless of whether they have an ACL reconstruction or are treated without an operation. Long-term studies suggest the rate of degenerative knee osteoarthritis 10 to 20 years after an ACL injury is more than 50 percent.

"For these reasons, I believe ACL tears in youth athletes are a growing problem, not just because we're seeing these injuries more frequently, but also because they can have significant consequences, that are both immediate and potentially long-term," says Pappas.

Life after surgery

For those who do require ACL reconstructive surgery, Pappas says it usually takes six to nine months to return to play.

For the first three months after surgery, the focus is on improving range of motion and strength. After four to six months, straight line "jogging" and sport specific exercises are added.

"So return to sport can occur as soon as 6 months, but depends on the motivation and compliance of the athlete. And having a dedicated and knowledgeable trainer or physical therapist is critical.

"This prolonged recovery time of at least six months also allows for more complete healing of the ACL," says Pappas.

He adds that a process known as "ligamentization," in which the body forms a new ACL ligament using the implanted graft as a scaffold), can take up to three years.

Reach David Quick at 937-5516.