Knee injury in child: Injuries rising among young athletes

I’ve written frequently about the numerous benefits of youth sports. Physical conditioning, decreasing obesity, socialization and camaraderie with friends and teammates, and so many other positive outcomes from sports make them important parts of the lives of our nation’s youth. But unfortunately there can be risks as well. A new study presented at The American Academy of Pediatrics annual meeting shows that knee injuries related to sports in kids are increasing at an alarming rate.

Researchers at The Children’s Hospital of Philadelphia presented the results of a review of the medical records from that institution from 1999 to 2011. Examining knee injuries that resulted from sports treated there revealed that not only have knee injuries in athletes under the age of 18 skyrocketed, but also the types of knee injuries have changed in recent years.

Knee injury in child a more common occurrence in sports

During that time period, 914 anterior cruciate ligament (ACL) injuries and 996 meniscal tears were seen, while 155 tibial spine fractures were seen. Tibial spine fractures increased approximately 1% per year, while ACL tears increased by over 11% and meniscal tears by nearly 14% over that time.

What I find interesting is the shift to more ACL tears from tibial spine fractures. Essentially tibial spine fractures are a variation of an ACL tear where instead of the ligament failing in its midsubstance, the ligament pulls the bony attachment off of the tibia. It has always been thought that young kids, especially before puberty and skeletal maturity, suffer tibial spine fractures, while high school and college athletes and adults suffer ACL tears.

Does a young athlete risk further damage by delaying ACL surgery?

ACL tears in kids increasing

This data suggests that younger kids are getting the injury traditionally seen in mature athletes. “Since tibial spine fractures were once thought to be the pediatric equivalent of an ACL tear, this continued rise in ACL tears in children suggests that injury patterns are changing and that the true incidence of these injuries is increasing,” notes J. Todd Lawrence, MD, PhD, the orthopaedic surgeon leading the study.

What is hard for me to know without seeing the actual data and just relying on the press release is the age breakdown of the injuries. One would expect ACL tears in high-school aged athletes, so looking at all knee injuries in patients under age 18 could be skewed toward a rise in injuries among patients aged 14 to 18. So whether the shift from tibial spine fractures to ACL tears is real is hard for me to know, but regardless, the rate that knee injuries from sports increased is still worrisome.

Should kids have ACL surgery?

There has been a lot of attention lately focused on ACL tears and surgery for skeletally immature athletes. It has been somewhat conventional wisdom over the years that delaying surgery to reconstruct the ACL in skeletally immature athletes was a good option, if not the preferred one, to avoid the risk of creating a leg length discrepancy or angular deformity of the knee by drilling holes in the growth plate. But that approach has been questioned in recent years, as several studies have shown a significantly higher incidence of meniscal tears and articular cartilage damage in kids who waited to have surgery.

In fact, a study published in the American Journal of Sports Medicine by the same authors at The Children’s Hospital of Philadelphia showed that meniscal tears that were no longer repairable and damage to the articular cartilage in the lateral compartment (outside) and patellofemoral compartment (under the kneecap) were much more common in kids who waited 12 weeks or more from the time of injury to ACL surgery. That suggests that the continued knee instability from the ACL injury will continue to tear up the young athlete’s knee, especially if the parents wait years. Plus, in my experience, it is really hard to keep kids out of sports for years, and often they are still too active just with playing with their friends to completely avoid the risk of further damage.

Knee injury in child

Take home points

So while these studies are certainly worrisome, I would caution against any urge to keep kids from playing sports. Again, in my opinion, the benefits far outweigh the risks. But there are two points I would emphasize. First, consider signing your young athlete up for an injury prevention class with a sports medicine group. Learning proper ways to land from a jump and ways to turn, as well as spending time with coaches learning proper techniques for the activities of that sport, might have a dramatic effect in reducing some of these knee injuries.

Second, I would encourage parents to take these injuries seriously. I know very well how much parents and coaches (and the kids themselves) want to play. But if a knee injury is keeping your son or daughter off the field or court or even just keeping him or her from playing as well as usual, it is worth seeing a sports medicine doctor and having it examined. Knowing that the athlete won’t make an injury worse or treating it appropriately from the beginning is crucial to keep kids in sports and healthy for many years to come.