I was wondering what are some medical reasons that require plastic surgery?

Function: Many plastic surgery procedures impact both form (appearance) and function (like reduced nasal breathing, hooded eyelids causing loss of visual fields, etc.). Those interfering with function are often considered as medical necessity to repair. Usually improvement or restoration of appearance does not fall in this category, and therefore not eligible for insurance reimbursement or coverage.

Most common is post-cancer reconstruction such as post-mastectomy breast reconstruction, head and neck cancer, skin cancer reconstruction, hand surgery, repair of congenital deformity like cleft lip and palate, etc.