This article appears in October Family magazine.

ACL injuries are on the rise, but injury prevention programs that include strength and conditioning can lessen the risk.

The rate of anterior cruciate ligament tears among children and teens has been increasing about 2.3 percent per year for the past two decades, according to the American Academy of Pediatrics’ 2017 study “ACL Tears in School-Aged Children and Adolescents Over 20 Years.” The peak age for injury is 16 for girls and 17 for boys, the study found.

“ACL injuries in young athletes continue to occur with increasing frequency. This is likely due to increased sports participation and more extensive training, including year-round sports participation,” said Dr. Paul Sherbondy, an orthopedic surgeon with Penn State Medical Group in State College.

The sports with the highest risk of ACL injury are football, soccer, basketball and lacrosse, Sherbondy said.

How it happens

The ACL is one of the four major ligaments in the knee and the most commonly injured. It connects the thigh bone to the shin bone and helps stabilize the knee joint. Primary causes of ACL damage during sports or fitness activities include:

— Pivoting on one firmly planted foot.

— Suddenly changing direction.

— Landing from a jump.

— Quickly stopping and starting.

“Females are more likely to tear their ACL compared to men. The reasons for this are not fully understood. It may be due to biomechanical differences in cutting, landing and pivoting,” Sherbondy said.

While collegiate athletes are usually provided with strength and condition programs to lessen their risk of ACL injuries, high school players may not be, often because of funding and coach awareness.

According to Sherbondy a reputable athletic program should include:

— Evaluating the individual athlete for strengths and imbalances.

— Exercises to strengthen leg muscles in a balanced manner.

— Exercises to strengthen abdominal and other core muscles.

— Training for proper techniques in jumping, landing, pivoting and cutting.

— Warm-up routine for injury prevention.

Athletes should always wear the proper protective gear, including sport-specific footwear.


When minor knee pain occurs, athletes should seek evaluation and treatment to prevent a small injury from advancing to a full ACL tear, Sherbondy said.

If a school doesn’t provide a strength and conditioning program, parents should seek assistance from a physical therapist or sports center to prevent injuries.

“There are numerous ACL injury prevention programs in existence,” Sherbondy said. “These programs seek to lower the incidence of ACL tears by addressing known risk factors. Part of the programs usually involve conditioning, jumping and strengthening exercises. There is particular attention to core muscle strength for body control, hip strengthening and knee positioning for proper landing mechanics.”

ACL injuries can range from a mild overextension to a full tear.

“Once an ACL is torn the risk of retear is about 10 percent. There is also an increased risk of tearing the ACL in your opposite knee,” Sherbondy said.

It’s a misconception that wearing a brace offers protection.

“Wearing a brace does not prevent ACL injuries. Sometimes a brace is worn as part of the rehabilitation process after the ACL has been fixed, but there is no science that says bracing prevents a retear, either,” Sherbondy said.