YOUR HEALTH: How you can prevent ACL injuries

DURHAM, North Carolina – Hattie Cutcliffe has loved gymnastics since she was a little girl.

"I was one of those kids who was rough and tumble just bouncing around everywhere."

That was until one day on the balance beam.

"I was doing a skill called an aerial cartwheel, which is essentially a cartwheel with no hands."

She landed off balance and tore her anterior cruciate ligament or ACL.

"There are over 400,000 ACL tears in the US each year," said researcher Dr. Louis DeFrate.

Many people may hear or feel a "pop" in the knee when the injury occurs.  They may also feel unstable, see swelling of the knee, and find it too painful to put any weight on it.   Depending on the severity of the injury, treatment may include rest and rehabilitation exercises to help regain strength and stability.

DeFrate and his research team at Duke University are studying the causes of ACL tears.

Hoping to prevent this type of injury, DeFrate and his team created a "stress test", combining MRIs of the knee with high tech X-ray imaging.

"We can see which positions the ACL is stretched the most and when it's most likely to fail," explained Dr. DeFrate.

Which can lead to better training programs for athletes and weekend warriors.

WOMEN AT RISK:  Women are more likely than men to have an ACL injury than men who participate in the same sports.  Studies have suggested some reasons for this.  Women athletes overall exhibit a strength imbalance in their thighs; with the muscle with the front being stronger than those in the back.  The hamstrings help prevent the shinbone from moving too far forward, a movement that can cause an overextension of the ACL.

"Perhaps working certain muscle groups to prevent the injury from happening," added Dr. DeFrate.

Hattie now coaches young girls gymnastics and teaches them the proper way to land and keeping young athletes active and their knees safe from injury.

COMPLICATIONS: People who experience an ACL injury may be at higher risk of developing knee osteoarthritis, which occurs when the joint cartilage deteriorates and its smooth surface becomes rough. Arthritis may occur even if someone has surgery to reconstruct the ligament. Multiple factors can influence the likelihood or risk of arthritis, such as the severity of the original knee injury, the presence of another related injury in the knee, or the level of activity after treatment.  (Source:

If this story has impacted your life or prompted you or someone you know to seek or change treatments, please let us know by contacting Jim Mertens at or Marjorie Bekaert Thomas at