Getting an edge on a very common youth sport injury

By Christina Camilli-Whisenhunt

- U-M researchers to focus on components of prevention training
programs that reduce ACL injury risk.
- New study will measure joint movements and the force of movements
performed on the athletic field.
- Results hope to give young athletes tools needed to play sports more
safely and improve performance.

Watch the video: http://www.youtube.com/watch?v=fwHT_GLNAvI

Research at the Bone & Joint Injury Prevention & Rehabilitation Center
(the Center) is moving a step closer to solving a problem that affects
at least 400,000 young athletes every year and causes them to sit on
the sideline for months.

Injuries to the knee anterior cruciate ligament (ACL)—one of four
major ligaments in the knee—is one of the most common youth sport
injuries, and the injury frequency has been steadily climbing over the
last decade. With kids becoming increasing active and competitive,
the rate of ACL injury has dramatically risen. These injuries also
have a steep price—nearly 70 percent of ACL injuries will lead to an
early onset of painful osteoarthritis.

The new study, led by Center members and Kinesiology Professors Riann
Palmieri-Smith and Scott McLean, will determine which components of
current ACL prevention training programs work best to reduce injuries.

Mclean noted this study is a critical step to help prevent ACL
injuries and osteoarthritis—a significant long-term consequence of
tearing the ACL. Osteoarthritis can reduce quality of life, and it is
well known that 5-14 years after an ACL tear, osteoarthritis can
develop. Within the coming decades we may have many young men, and in
particular young women, requiring knee replacements by the time they
are in their 30s.

Current ACL prevention programs have athletes training three times per
week at 90 minutes per session. Palmieri-Smith said, "While these
programs are showing significant promise, what we tend to see are kids
getting overwhelmed because these programs are extra training on top
of what they are already doing. We see a lot of kids drop these
training programs completely, because they think they are too much
work and cut into their practice time."

The study's main focus is to uncover the key components from the
typical 90-minute prevention program that reduce the risk of injury.
To test any type of prevention program, you first have to know if it
improves something. To do this, Palmieri-Smith and McLean are
bringing in 120 females between the ages of 10 and 18 to the Center's
lab. They will measure their joint movements and forces typically
performed on the athletic field, such as landing on one leg or
pivoting to the side.

Once all subjects are pre-tested, they will be placed into one of four
different, six-week prevention training programs: Core stability and
balance, plyometrics, neuromuscular training, or a control group. At
the end of the six-week program, the subjects will come back to the
lab and U-M researchers will assess the differences between movements
performed before the training program and compare them to the
movements after the training. They will evaluate the success of each
of the training program components (including the control group) in
being able to modify otherwise hazardous landing maneuvers.

McLean says there are known movements that increase ACL injury—like
landing with a knee too straight or even landing knocked-knee. He and
his colleagues want to find out if any one of the isolated components
of current ACL training will successfully modify an at-risk movement,
for example, the way a person lands—with knees more bent or aligned
straight versus knock-kneed. Once the team analyzes all the data,
they hope to come up with an improved and far more efficient
prevention program that coaches, parents, and kids will be more
inclined to incorporate into an athletic routine.

U-M researchers anticipate that by changing the way people move and by
making them more aware of how their bodies move, ACL injuries will
finally begin to decline. Palmieri-Smith added, "We hope to give
young athletes the tools needed to play their sport safer and at the
same time improve their performance in both strength and speed on the
field."

About the Center
The University of Michigan Bone & Joint Injury Prevention &
Rehabilitation Center is a collaborative effort between the Medical
School, the College of Engineering, the School of Kinesiology and the
School of Public Health. The Center's mission is to excel in the
creation of new knowledge in all areas relevant to the prevention,
treatment, and rehabilitation of musculoskeletal injury and arthritis.
The Center is dedicated to conduct mission-driven research, train the
next generation of multi-disciplinary researchers, provide leadership
for local, national, and international collaborations and
partnerships, promote the effective translation, use, and exchange of
knowledge and develop organizational excellence.