Injury Prevention: A Systemic Approach to Test Selection
Bottom Line Up Front: The individual tests selected for an injury prevention system are important and should certainly possess basic psychometric properties (reliability, predictive and discriminant validity, etc.). However, it is important to use a systematic approach for injury risk factor identification and management to ensure that a comprehensive and effective plan is provided for each individual under your care.
What to Test
Which tests should be used in an injury prevention system? It boils down to identifying and managing the known risk factors for injury. What are the most common neuromuscular risk factors for injury? They can be summed up in three categories:
- Previous injury
- Abnormal motor control (due to abnormalities in ROM, stability, coordination, balance, etc.)
Let’s look at how a successful injury prevention program, the FIFA 11+ , addresses these risk factors. There is good research showing that the FIFA 11+ successfully reduces injury rates. The researchers who developed the FIFA 11+ program address many of the neuromuscular factors related to injury, including core and leg strength, balance, and plyometrics/agility. Thus, a soccer player who has poor core strength gets a little dose of core strengthening to address his deficit (plus the other stuff he may or may not need). This a program that I highly recommend, particularly if the alternative is doing nothing. But the problem with this ‘one size fits all’ approach is that it doesn’t test any of the factors it is attempting to mitigate. There are no feedback loops and ironically, it is inefficient because of its efficiency of quickly addressing many factors in a warm up session. It gives everyone a small dose of the same thing.
Let’s consider a school that has identified children who are not reading at their grade level. A program is implemented requiring all students to spend 30 additional minutes per day performing phonics and reading. Sure, a program has been implemented to address the problem, but what about the kids with dyslexia, vision problems, or those who struggle with the alphabet? Much like the FIFA 11+, this program will help those who are ripe for it, but will not affect those who have risk factors which exclude them from benefiting. Again, the research is clear, group programs work for those athletes that they work for….but not everyone.
With regard to injury in soccer, which tests would you perform to identify all the different root causes of all the different potential injuries? This is the current dilemma in injury prevention research.
What is the solution? Systematic injury reduction requires a level of individualization. Let’s consider the Lehr et al study. Prior to the season, athletes were given a questionnaire, Functional Movement Screen and Y Balance Test. The move2perform algorithm was used, which looks at the interplay of several risk factors. For example, having pain on a test trumps movement and Y Balance Test scores. Individuals with pain land in the highest risk category. If someone has a previous injury AND motor control dysfunction, as identified by the Y Balance Test or Functional Movement Screen, they are in the second highest category. If they have no previous injury or discernible motor control dysfunction, they are in the lowest level risk category. For someone in the lowest risk category, I would proceed to higher demand screening for power, energy storing, and postural integrity under load (Fundamental Capacity Screen). However, the path would be different for those in the other risk categories.
One of the biggest mistakes I see when choosing screens is honing in on the predictive validity of a test in isolation and trying to find a single, best screen. In reality, musculoskeletal injury is multifactorial and incredibly complex. While the screen(s) you choose should be reliable, modifiable, have discriminant validity (i.e., distinguish between those with and without the disorder), and be predictive of the outcome desired outcome (e.g. injury prediction, performance improvement, identifying the barriers to skill development), it is vital to recognize that having a system that directs to multiple intervention paths is crucial. I cannot foresee a day when one screen or test will be sufficient to predict musculoskeletal injury.
An injury prevention system must be based on principles and procedures using an organized, algorithmic approach that is rooted in research. Using the Functional Movement System for injury prevention considers the interplay of the tests being used, the hierarchy of how the tests are administered and how the results are addressed. Further, it contains vital feedback loops and gives individualized action steps based on the results. As test results change, so do the action steps.
A comprehensive injury prevention system protects you from selecting isolated tests designed to identify only a certain risk factor or from attempting to manage risk factors with an injury prevention program for individuals who will not benefit.
What risk factors do we look at in our injury prevention system?
Pain with movement
Y Balance Test Composite risk cut score based on gender, sport, and competition level
Y Balance Test Asymmetry
Functional Movement Screen 0’s and 1’s
Remember, these are used to identify AND manage the most common risk factors for future injury of pain, previous injury, and abnormal motor control.
In upcoming posts we will discuss how to physically accomplish getting these risk factors tested and what to do with the results.