I love being the provocateur!
In the past we used to follow this model:
1. Make a diagnosis (eg plantar fasciitis)
2. Do a gait analysis to look for the abnormal function that might be causing the diagnosis (eg excessive foot pronation)
3. Do a weightbearing and non-weightbearing assessment to:
a. Explain the abnormal function seen in the gait analysis (eg tight calf muscles)
b. Derive a foot orthotic prescription, if foot orthotics indicated.
The world seemed to work pretty well when doing it this way. At least that was the way we taught the students to do it.
Now we know that abnormal function, alignment and posture are not a problem. The problem is the forces behind the function and someone can have still have normal function, but the forces may be abnormally high. It these forces that do the damage to tissues that hurt. Abnormal motion is not painful.
So the question is now, how can you see these abnormal forces as part of a gait analysis? The answer is you can’t.
I also challenge you to think about what information you get from a gait analysis? What do you do with this information? Does this information change your foot orthotic prescription? What is the ethics of doing any clinical testing, if the outcome of that clinical testing has no potential to change your treatment? ... think about it!