It is a movement based diagnostic system which systematically finds the cause of pain - not just the source - by logically breaking down dysfunctional movement patterns in a structured, repeatable assessment.
Look at it this way. When you head to the hospital for shooting arm pain, the immediate course of action is to check your heart, not your arm. The symptoms down your arm are just a result of a problem elsewhere in the body. Similarly, the SFMA focuses on underlying dysfunctional movement to find the cause of pain, not just the source. This concept is better known as regional interdependence - how seemingly unrelated problems are actually driving the dysfunction.