And, as hinted elsewhere, it's a rare surgeon who maintains absolute silence and does *not* listen to music in his O.R. Simply because you saw Callie drilling into a knee with heavy metal blasting 3 episodes ago doesn't mean that only orthopaedic surgeons listen to music, or that it's even a bad idea. One of the txplant surgeons here listens to jazz whereas the plastic surgery department prefers classic rock; incidentally two of the orthopaedic surgeries I've scrubbed in on had classical music as the soundtrack and the only place I've heard anything that approached heavy metal was in a liver resection.
As a sidenote, there are plenty of articles out there that have shown an increase in productivity and efficiency with music playing in the business field; why would the OR be any different?