Mick: So you've also got an interest in ACL prevention. What's the literature currently telling us about ACL injury prevention programs, in terms of reducing injuries, and what are the key components of a successful program?
Brooke: So there's a lot of strong literature around ACL injury prevention. Recently, there was a meta-analysis of meta-analyses - so you can't really get much stronger evidence than that – that reported ACL injury prevention programs reduce all types of ACL injuries by 50%. This research also showed that ACL injury prevention programs can decrease non-contact ACL injuries in females by 67%.
In regards to what are the key components? At the moment we don't really know what component of these evidence based programs is having the greatest effect. And it's likely that it's probably a combination of things that include some lower limb strengthening, core strengthening, balance/proprioception and movement drills that looks at jumping and landing and changes of direction.
Then there's the big picture things that we often forget about which are sometimes under-rated: ie. your general health and well-being, recovery practices, sleeping, eating, hydration, sport-specific skills and load management. All of these things play a role and should form part of the education of an injury reduction program. These aspects are historically hard to measure, monitor and implement, and the current evidence is very much focused on that 10-15 minute warm-up prior to training and games.
Mick: Excellent points Brooke! So despite the solid evidence of the success of those injury prevention programs, not all clubs, coaches, and players adopt them right? So what are these barriers as to why some coaches, clubs, and players aren't adopting these programs?
Brooke: There's definitely plenty of barriers in the real-world situation. I guess it's all great when there's a research trial, and you're getting monitored, and there might be external motivation to do the program, but as soon as that stops we know there's low uptake of the injury reduction programs.
Alex Donaldson and colleagues have done a lot research into why that is. One reason is that coaches don't know if they have the knowledge or skills to implement the programs without the support of research or allied health staff.
Research has also shown us that some coaches don’t believe that the program is related to their sport or they have the time to allocate the activities into their program. So, if we're talking about football, they don't believe the exercises in the injury prevention program are helpful or related to football. Combine that with the fact that their time at training is often limited, they don't want to spend 15 minutes doing these warm up exercises and strengthening exercises when they've only got an hour with their athletes.
Mick: Is there anything that can be done to overcome these barriers?
Brooke: Design of programs needs inclusion of education to rationalise why things like jumping and landing technique, change of direction technique will also improve football performance – i.e. studies have shown these programs improve vertical jump, speed and agility testing. The design and implementation of a program should also consider the sport specific skills (i.e. evading or tackling) the activities (i.e. change of direction) relate to and incorporate them into the warm-up. Programs should also be concept based, not prescriptive, so coaches can adapt them to their setting, in fun and creative ways.
Mick: Now even when there is successful implementation of ACL injury prevention programs, injuries can still occur, and I think that that's a big thing that people need to understand. Are there certain groups that are more likely to get injured despite the program being there in the first place?
Brooke: So if we're talking about groups of people that are specifically at a higher risk of sustaining an ACL injury, we know the biggest risk factor is “exposure”, especially in high risk sports. So here in Australia our high risk sports are netball, AFL and soccer, and you’re more likely to tear your ACL if you're participating in those sports. However, the relative risk is low, and we know the benefits of participating in sport far outweigh the risks or consequences of injury.
Research has also shown that the rate of ACL injuries are are going up in 10-14year old kids, and that kids that are more likely to sustain an ACL injury are less physically active than their peers.
The other known subgroup of higher risk is being female; largely due to the anatomical and biomechanical differences that don’t favour the female athlete. Also if you have a previous history, or family history the risk is increased. Approximately one in three under the age of 25 will sustain a second ACL injury (either limb) in the first 2-years following an ACL injury.
Mick: You're a player in the AFL Women's competition, a code that unfortunately has a well-publicised ACL problem. Do you have any insight as to why there's been such a large number of ACL injuries that have occurred in the first 2 years of its competition?
Brooke: The recent data that came out suggests that AFL women have a 9x greater risk of sustaining an ACL injury in a game compared to the men when they've accounted for exposure (i.e. shorter season). This is high compared to other female sports previous research will show that females are 2-5x more likely to sustain an ACL injury compared to their male counterparts. I think it'll gradually regress down a little bit over the upcoming seasons as we have a relatively small sample size of two 8-week seasons.
The AFL Women’s competition is also a relatively new sport for most of the athletes. Even though they've been playing other high-risk sports (e.g. netball, soccer etc) and coming across to AFL. It’s also a very unique sport in that it’s 360 degrees in nature, and very unpredictable.
Also it’s a newly formed professional competition, and the athletes have not previously been in elite pathways for football, or even in elite pathways in other sports. So I think there's a lot of different factors at play, and we need to focus on the things we can control – targeted female, sport specific strength, conditioning and movement training, and player wellness. And continue to investigate mechanisms and risk factors for injury, return to sport criteria for high risk athletes, and reinjury. I think that it will be interesting to observe the rates of ACL injuries over the next few years, as the community level and elite level competitions continue to grow.