"Back in the day DOs could also do musculoskeletal manipulation."
In 1993 I was in a pretty nasty car crash. Got rear ended. I hit the seat hard enough that I sheared off the seat back adjuster and had a really nice seat belt bruise from my shoulder down to my hip.
I got the first available appointment with the practice I was going to at the time; my MD couldn't see me, but his partner, a DO, could, and he took me through that several week recovery period, including doing a number of adjustment on my neck, back, and shoulder.
Matter of fact, he's still practicing. I'll be damned. Unfortunately it's not at all convenient for me to see him.