Native American stretching exercise?

A few years ago, I had just finished playing a gig with a band, and a man introduced himself as a Native American healer. He offered to do a stretching exercise to relax my arms, and after seeing him do it with a friend, I agreed. He gripped my arm tightly with both hands up near the shoulder, and then gradually pulled his hands down towards my wrists while twisting his hands left and right in a "wringing out" motion. It was a unique sensation, and did sort of feel like something fundamental in my arm--like a tendon or nerve--was being gently stretched. I suspect my 'funny bone' nerve may have been involved, since there was a mild tingling or vibrating sensation from my shoulder all the way down to my fingertips.

I've always wondered exactly what he did. I think the 'Native American' aspect helped it stand out in my memory--ancient secrets and all!-- but it may have been just a standard massage or chiropractor technique. Obviously there was nothing magical going on, but it was a unique experience and I'm curious if anyone can make an educated guess as to what he was doing.