In the past two blogs we have outlined the statistical risk of not only suffering an ACL injury, but also the risks of sustaining a recurrence of ACL rupture following ACL reconstruction (ACLR). We also delved into the risk to females, the inexact time frame to return to sport, and talked about whether you actually need to have a reconstruction! And in the final part of Blog 2 the take home message was a rigorous and progressive rehabilitation program, based around specific functional testing criteria, and performed for a minimum of 6 months, is essential to reduce the risk of recurrence of ACL rupture following reconstructive surgery.
But what about preventing ACL injuries in the first place? We are lucky to have some great information that came out of research based on soccer injuries: The medical research centre of FIFA (Federation Internationale de Football Association – the global governing body of football, or soccer) developed a soccer specific prevention program (called the FIFA 11+ program: http://www.footballfedvic.com.au/fifa-11plus/) that has been scientifically proven to reduce the incidence of injuries in soccer. The program includes some key exercises that are critical in injury prevention programs – core stability, strengthening of thigh muscles, balance, dynamic stabilisation and plyometric or jumping type drills. This warm up program takes only about 10 -15 minutes, needs no equipment, and is designed to replace the normal warm up session, so if anything it saves time.
Due to the success of the FIFA 11+ program, other sport specific injury prevention programs have been adapted from this original one and we now have programs specific to Australian Rules Football (http://www.aflcommunityclub.com.au/index.php?id=906 ), Netball (https://knee.netball.com.au/), and junior soccer.
The importance of these Injury Prevention programs cannot be under stated – research indicates that utilising these programs can reduce the incidence of all ACL injuries by as much as 65%, and can reduce non contact ACL injuries in females by 66%. These programs are also showing reduction in all lower limb injuries by 22%.
So … why aren’t these programs a standard part of all our warm up sessions? It would seem that purely a lack of awareness is the problem, because the research shows us they are incredibly effective in injury prevention (and performance enhancement for that matter), they only takes 10-15 minutes to complete, and anyone can supervise the warm up once the exercises are learnt! So get clicking on those links and start implementing the program for next season!
And finally, as promised, here’s a bit on how kangaroos may hold the key to the ACL future!
Over time, there has been a wide variety of different methods used to try and improve the outcomes of ACLR. Time frames have been discussed in our earlier blog – what is interesting to note is that we are actually pretty conservative in Australia with our time frames, taking on average 10-12 months until return to sport, and even longer for many of our adolescents. In the English Premier League players return at around the 6 to 8 month mark, and in the NFL it’s even quicker than that (3-5 months). So it would seem that time isn’t our greatest problem.
Another variable over time has been the type of graft used – in a reconstruction, surgeons take a graft from another part of our body and transplant it to act as a new ACL. Originally, the patella tendon (below the kneecap) was the preferred graft tissue (but this seemed to cause a lot of problems with knee pain in jumping athletes, especially basketballers and netballers). Most recently the hamstring has become the graft of choice for many surgeons, but losing a part of the hamstring muscle group has left athletes (especially in kicking and sprinting sports), very vulnerable to chronic hamstring strains. In between there has been artificial grafts (LARS) and donor grafts (from dead bodies) but the most recent trend sees a shift towards using the quadriceps tendon (just above the patella) due to the thickness of the tendon (and therefore graft) that can be obtained. No matter what, it just seems that a human tendon cannot function quite as well as the original ligament itself.
So here’s where the kangaroo may come in and save our ACL’s! It has been shown in recent research from Sydney University, that kangaroo tendons from the tail or hind leg are about 6 times stronger than a human tendon. Even the weakest kangaroo tendons were 2-3 times stronger than our own! Not only are the roo tendons so much stronger, but they’re also longer which is critical in ACL reconstructions, as the tendon tissue, if long enough, can be looped into bundles for even greater strength.
But the kangaroos are probably pretty safe for now – to progress from idea to implementation can take many years, and reality tells us that many ideas don’t survive past early testing procedures anyway. Just being able to transplant a foreign body from an animal into a human will be a major hurdle due to infection and rejection risks. But … you never know!
What we do know, and the take home messages from our 3 part blog series are:
- ACL injuries do happen in sport, and type of sport/genetics/sex all play a role in risk. However we do have some great Injury Prevention Programs that should become a standard component of all our sporting warm sessions.
- When you do have an ACL reconstruction, keep in mind:
- For most people, there is rarely the need to return to sport in under 10-12 months.
- Your rehabilitation is critical and should be performed under a physio/strength & conditioning trainer who uses a criteria based rehabilitation program (achieving functional goals and passing ACL specific tests), not one who purely uses time frames.
- Rehab should continue vigorously for a minimum 6 months (and in reality a bit more).