An odd rules abstraction people often forget is that the main type of healing spell in D&D doesn’t technically heal *real* actual damage and injuries like lost limbs and such, it only recovers “HP”. You need more specialized, much healer spells to do that. Or rules loophole it by just murdering the person and then rezing them because that spell just so happens to fix all sorts of conditions that would normally be unfixable at that level. Hell, 4th edition took this to such a stupid extreme that by the rules as they were written it was easier to raise a person back from the dead than than to actually try to cure most poison effects.