I have to confess my ignorance. I've never heard the name. I'm curious, though, and want to look into it.
Birba: Otto Ortmann was a Johns Hopkins guy, director for a time at Peabody Conservatory, who obsessed on piano mechanics, sitting for years in his laboratory measuring, taking X-rays, studying visiting virtuosi, trying to come up with basic rules of piano technique and hand physiology during 1917-1942. His 400-page book, Physiological Techniques of Piano Playing (1929) is out of print, and, as thalbergmad suggests, pretty dry stuff.
As far as I can tell, some people love him, others think he was a fool. Most probably, the value of his work lies somewhere in between.
I'm not aware of any physiologists duplicating his work (the gold standard of the scientific method), although it's possible. Whenever I read of those enthralled by his scientific approach to art, I think of what Hans von Bulow (the guy married to Cosima Liszt and cuckolded by Wagner, a conductor who made his orchestra memorize their parts--another odd duck) said to a member of his audience at a concert who complained there were not enough seats on the left of the auditorium, allowing visualization of the pianist's technique:
"One plays the piano, madam, with the brain, not with the hands."
Glenn
P.S. After enjoying your Kabelevsky and Ginastera, I don't think your technique needs much help from Ortmann.