English Expression: Go under the knife
Nobody wants to go under the knife, which is a euphemism for having an operation, but sometimes it is a necessary evil that must be endured.
It’s one of the miracles of modern medicine that a person who is exceptionally sick can have an operation, and be perfectly healthy within a few weeks.
The outcome is something to look forward to but going under the knife, especially if you are not going to be put under, is one of the necessary evils of which people are afraid.