of acute knee injuries in adolescent female football players: cluster
randomized controlled trial.

M, Atroshi I, Magnusson H, Wagner P, Hägglund M. BMJ. 2012
May 3;344:e3042. doi: 10.1136/bmj.e3042.
(full text available for free)

is a popular sport throughout the world; however, female soccer athletes are
much more prone to anterior cruciate ligament (ACL) injury than their male
counterparts.  One theory why female
athletes are more prone to ACL injuries involves the different firing patterns
of the muscles in the lower extremity in women compared to men, which leads to
increased valgus load at the knee in females.  Considering this hypothesis, is there a short,
effective, and applicable intervention that could be implemented on a large
scale to help prevent ACL injuries?  The
aim of this randomized clinical trial was to evaluate the effectiveness of a
neuromuscular warm-up program to reduce acute knee injuries, and more
specifically ACL injuries, among adolescent female soccer players.  In this study, 4564 female soccer players
between the ages of 12 and 17 years (in 309 soccer clubs) were randomly divided
based on their teams into two parallel study groups: control group (2085
athletes in 155 clubs) and intervention (2479 athletes in 154 clubs).  A neuromuscular
warm-up program
was designed focusing on knee control and core stability
and was comprised of 6 exercises, further subdivided into four steps with
progressive difficulty.  The program took
about 15 minutes to complete and was implemented in the intervention group and
maintained through the entire duration of the soccer season.  The study staff taught the program to the
coach and one player on each team.  Compliance
was monitored by coaches during each training session in addition to random
spot checks by physiotherapists
throughout the study duration.  Coaches also notified the physiotherapists of
any knee injuries and the clinician then conducted an evaluation.  Severe knee injuries were defined as an absence
from play for more than four weeks.  The
authors noted that the intervention group had less ACL injuries (7 injuries,
0.28%) than the control group (14 injuries, 0.67%); a 64% reduction.  However, there were no differences between
the groups in regards to the additional end points of severe knee injuries or
any acute knee injury.  The authors
provided some evidence that severe knee injuries or any acute knee injuries may
have been lower among those considered compliant with the intervention program
compared to the control group.

findings of the study suggest that a structured 15-minute neuromuscular warm-up
program can help reduce the number of ACL injuries in adolescent female soccer
players.  One advantage of such warm-up
program is that it is monitored and implemented by the coaching staff and only
requires minimal outside intervention. 
Therefore, it can serve as a preventive tool for ACL injuries in female
adolescent players.  The impact on ACL
injury prevention by a neuromuscular warm-up program was also echoed in a previous
study by
Mandelbaum et al.  It demonstrated that a neuromuscular and
proprioception training program may help reduce the occurrence of ACL injuries
over the long-term.  In summary, more research
is needed to establish the validity and clinical benefit of neuromuscular
warm-up programs to prevent ACL injuries specifically and all knee injuries in
general.  The biggest limitation of this
study is that it was neither designed nor powered to look at the rate of injury
reduction during contact vs. non-contact ACL injuries with and without a
neuromuscular warm up.  Do you
incorporate a neuromuscular training program with your adolescent females?  Do you think these findings may be applied to
other female sports as well as male sports?

by: Christian Glaser, DO and Marc I. Harwood, MD reviewed
by: Jeffrey Driban


Waldén M, Atroshi I, Magnusson H, Wagner P, & Hägglund M (2012). Prevention of acute knee injuries in adolescent female football players: cluster randomised controlled trial. BMJ (Clinical research ed.), 344 PMID: 22556050