It's called "Seven Spine Surgeons on Implant Reps in the Operating Room."
Here's part of one of the seven responses (don't want to publish an entire probably copyrighted article):
Sometimes there are issues with case sterilization, or even with instrument failure, and the rep is able to get the needed implants to the room (usually faster) than the OR nurse.
Especially with new technologies, the OR staff is probably not accustomed to the implants or hardware. The rep is able to instruct the team in steps required.
As a surgeon, I do not depend on having a rep in the room. But as far as ensuring quality care, I feel that there is an important role for the instrument rep in helping the scrub tech prepare for the intraoperative requirements of the surgery.
The rest of the article is here.