1.5 The Law of One Cause

Many seemingly unrelated injuries can be caused by one underlying element. To help illustrated this idea see Figure 9. Here we see how dynamic valgus is correlated or linked with many injuries. This idea, where many injuries are caused by one cause is the Law of One Cause.

Figure 15: Law of One Cause (Example Dynamic Valgus or inward movement of the knee – CMD3)

1.5.1 Signs Vs. Symptoms

Our research indicates that over 90% of developing athletes have some level of dynamic valgus above a depth position 3 (See FITS Depth Standards in Unit 2). Many of these athletes are asymptomatic or they don’t feel any discomfort, yet when they land, run, squat and play sports they do so with non-ideal knee control. How are these athlete’s not in pain? Shouldn’t they feel something?

Figure 16: Signs Vs. Symptoms Graph A) Sign, B) Asymptomatic Period, C) Symptom Threshold, D) Tissue Aggravation Level, E) Symptom

The answer has to do with the difference between signs and symptoms and the asymptomatic period. See Figure 10.
Signs are something observable that is a concern. A symptom is something the athlete themselves feel. For example, dynamic knee valgus is a Common Movement Problem that is a sign. It’s a concern because we know that it leads to a laundry list of problems – See the LAW OF ONE CAUSE. The period where there are no symptoms with a sign is called the Asymptomatic Period. Once the athlete feels something there are now symptomatic.
It is important to realize that it takes time for a sign to become symptomatic. That’s because our tissues’ are resilient. They can tolerate a lot and they heal when there is enough recovery time or rest. More importantly, the reason why they are symptomatic is because they have a sign or a Common Movement Problem. If we fix the Common Movement Problem so they don’t show a sign, their symptoms will likely disappear. Note, once there is pain, it’s important to see a health care professional to rule out other possible causes.