Appendectomy
An appendectomy was the surgical removal of the vermiform appendix. It was not considered a major surgery.

Elias Sandoval underwent an appendectomy some time prior to 2264. The appendix later grew back when Sandoval was exposed to the Omicron spores. ()

In 2372, The Doctor mentioned that he had performed three appendectomies since his activation the previous year. ()

In 2377, B'Elanna Torres compared performing gene re-sequencing on her unborn daughter (which would lead to the non-development of, among other things, a third lung) to a prophylactic appendectomy. ()

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Medical procedures