I would imagine they meant the skill of plastic surgery, though I'm not sure either way if that's true either. I suspect not, depending on the definition.
So I could well imagine ancients doing things that would count as "plastic surgery". I rather doubt they "perfected" it, though...
[1] Wikipedia says so, must be true :-) https://en.m.wikipedia.org/wiki/Plastic_surgery
However, the Romans had enough patients over a continuing period of time to perfect plastic surgery.
So I think you're confusing emergency surgery and piercings with the art of plastic surgery.
If you think anatomical knowledge was universal, that's not true either. Japanese doctors were ashamed when they saw the first anatomy book - they had known nothing beforehand.
The US had to dig up bodies from graves at night for decades to draw those books.