Anterior Cruciate Ligament injury prevention – Part 2
Last post, we discussed the anatomy and mechanics of the ACL, as well as what predisposes it to tears. This post is going to consider the more important, practical, part: how do we reduce ACL injury risk?
What can we do to reduce risk?
- Basic exercises:
We can most certainly work on improving strength or flexibility deficits that we see in a thorough physical examination. These are easy things to work on – a no-brainer! We even have research to help us decide on the best exercises for these issues. However, basic exercises alone are not enough.
- Neuromuscular control:
We need strength and flexibility, but the application of these is even more important. Recent research has focused on the neuromuscular control of the lower extremity. In other words, how are the joints controlled and kept in optimal positions when they are under load and stress? The key word here is “neuro”, in that there is a component of injury risk reduction which is reliant on the brain or is learned. A recent systematic review1 out of Australia found that the available data suggests that 26% of non-contact injuries could be prevented with neuromuscular programs. Although there are not yet enough studies with enough participants to make this finding statistically significant, it does suggest that the most useful application of neuromuscular programs would be in high-risk sports such as soccer.
So, what is an example of a neuromuscular program?
A good example of an injury prevention program that employs a high level of neuromuscular exercises is one developed for soccer: the FIFA 11 plus:
Fifa 11 plus manual
(Check out the sidebar (desktop) or below the article (mobile) for other Fifa 11 links)
This training program focuses on dynamic drills and exercises that not only build strength, but require neurological engagement. For example, rather than just doing static leg raises or planks, it calls for lateral jumping drills or single-leg squats. A recent systematic review2 found that this program does improve neuromuscular control and significantly reduce the number of injuries in male and female amateur soccer players. While not specifically focused on ACL injury prevention, the overall effect of increasing strength and neuromuscular control will be expected to reduce ACL injuries. The program is generic so that it can be applied to a whole team, but as our previous post showed, some people are at greater injury risk than others, so a neuromuscular program may be even more important for this high-risk population.
Is there a way to screen people for injury risk/poor neuromuscular control?
The Landing Error Scoring System (LESS) is a tool for identifying high-risk movement patterns. The tool has good measurement reliability and has recently been shown3 to be effective in predicting ACL injury in soccer players. With this measure, the athlete stands on top of a 30cm box, placed half their height from the landing area. They jump forward to the landing area and immediately jump for maximal height straight upwards. The task is recorded on video from the front and the side. The video is then replayed and scored against the LESS. A higher LESS score indicates a greater number of landing errors and therefore a poorer technique. This way, the high-risk individuals in a team or group of players can be identified. While all athletes can benefit from a neuromuscular program, those in the higher risk category may benefit from closer follow-up and re-testing. The study suggests a score of 6 or higher as being high risk in soccer players. The videos below show the test in action and the footage we collect:
In this example we identified three small faults:
- Not enough knee flexion on initial landing
- Too much rotation at the foot
- Knees falling inside of the medial foot
These faults thankfully only put her in the low risk category! Even so, we can work to reduce her injury risk further by correcting these small faults. In this patients’ particular case, the faults seen correlate with physical findings of over-pronation, which can be corrected with appropriate footwear. The knees falling inside of the medial foot is a very common finding in young female athletes, and can also be caused by weak gluteal muscles. This underscores the need for a thorough physical exam in coordination with the video analysis – the video alone showing the knees falling is not enough to determine the underlying cause of the fault.
Understanding the anatomy and mechanics that leads to injury is important. A Physical Therapist has the training to do this. However, keeping up with the growing evidence base is equally important. That is why PhysioWorks, Sports and Wellness, Inc has focused on the sporting population, particularly with respect to injury prevention. We are devoted to staying up-to-date with the latest sports-science research. We have also invested in professional-grade equipment to perform LESS in the clinic or on the field. We hope to be able to work with local soccer clubs, teams, individual players, and parents to introduce this to our local community. By doing this, I hope that we can reduce our athletes’ risk, so that we will not have to conduct as much rehab on surgically-reconstructed ligaments! Following this link to the page about our ACL injury prevention screening service.
2) Barengo NC, Meneses-echávez JF, Ramírez-vélez R, Cohen DD, Tovar G, Bautista JE. The impact of the FIFA 11+ training program on injury prevention in football players: a systematic review. Int J Environ Res Public Health. 2014;11(11):11986-2000.
3) Padua DA, Distefano LJ, Beutler AI, De la motte SJ, Distefano MJ, Marshall SW. The Landing Error Scoring System as a Screening Tool for an Anterior Cruciate Ligament Injury-Prevention Program in Elite-Youth Soccer Athletes. J Athl Train. 2015;