Yitzhak Schotten played in my father's viola section in the Boston Symphony in the late 1960s and early 70s. My father often referred to him as "Dr. Shotten," and as a child I always thought that he must have been a medical doctor as well as a musician. I wondered what would happen if he got called to perform emergency surgery during a concert. Holding a high degree in a non-musical field wasn't that unusual to me. My father sometimes got mail addressed to "Dr. Fine" (because of his Ph.D. in chemistry), and Charles Kavalovski, the principal horn at the time, had a Ph.D. in nuclear physics.
Perhaps my father's "Dr." title was an affectionate one, since Yitzhak Schotten is such a smart man.
His video about the bow arm is excellent. I'm posting it here so that I know where to find it. I hope you like it too.