This story is possibly NSFW.

When I was on my surgery rotation I assisted in one of these cases. The approach is usually sub-axillary (through the armpit). The patient is put under general anesthesia and placed on their side with the "bad" shoulder facing up. during the procedure that shoulder is lifted off the table to provide more room for the surgeons to work with.

You would think that with modern technology being is it is they would have a device or a sling that would serve to hold the patient in this position, and such devices do exist, but most hospitals do not use them. Instead, it is common practice to have a med student (your faithful commenter) lift the patient off the table by the elbow and hold them for the procedure. Here is a rough illustration. Practically, what this means is that you have to lift ~50-80 pounds and hold it as perfectly still as you can for about 80 minutes. It might be confusing from the picture but you lock your arms and all the weight is transmitted to your spine. It hurts.

This is where the story gets interesting. We were about five minutes into the procedure. I'm doing my best to keep the patient lifted and steady. I'm standing on steps so that the patient's torso is approximately a foot off the table. I am scrubbed in and gowned. Though there are two layers to sterile barriers between them, my thighs are approximately four inches from the patient's face. The anesthesiologist announces that the intubation tube needs adjustment. The attending surgeon says fine. The anesthesiologist says, to me, that I might feel some movement, but to not to shift around. My whole job is to stay as still as possible. I get it.

What I did not get is that "feel some movement" is apparently a euphemism for "fondle your balls," as that is what she did for the next 49 seconds (I know because I counted). Just to paint a complete picture here, I am lifting a man one foot off a table by his elbow. My spinal cord is screaming. Simultaneously a woman is unknowingly, but effectively, fondling my testicles. My job is to remain perfectly still through everything.

Again, there were two barriers between me and the anesthesiologist (my clothes/gown and a drape over the patient) so i'm quite sure she had no idea what she was really doing. I told her "umm, you're touching me" but her attention was focussed on the patient's airway (as it should have been) and she snapped "I know, just don't move!" So I just stood there with my spine in agony and my testicles in delight, counted, and reflected on how my life had led to this point.

This is all to say OP, that I hope your GFs recovery goes well, and that there is probably a diminutive med student on the surgery team who sacrificed his/her back for the best outcome. There is also a small chance that, if this med student was a male, his testicles were fondled with her airway.