in my experience of what Dan and others are doing, it has as much to do with the mental state, as the musculoskeletal condition/ing. As for these things being separate from a spiritual component, how can you have spiritual, without mind and body and vice versa?
That's a bit like saying "How can you have a sandwich without mayonnaise?" It's not on me to prove that; that's a whole separate discussion, and not one that I care to engage in in current company (in other company, I might, but this one? hell no). I'm simply pointing out that when you're using two similar (but not the same) terms that are composed of words that have multiple meanings, it's a mistake to assume or assert that the two parties using them mean the same thing.