Healing in the House of Elrond

[Lalwendë]

I won't pretend to have extensive medical knowledge but I do know that sometimes 'foreign bodies' can be better left within the injured body than removed straight away, or even at all. Knife wounds are particularly bad news as the body receives a double blow of damage as the blade passes through the flesh twice - going in and then coming out again, unlike a bullet which tends to go in and stay in. So for Aragorn or anyone else to have attempted to remove a splinter of blade out in the field would have been very risky, medically speaking, and it was probably best to leave it alone.

On the topic of Elves having healing powers, I was thinking about this the other day. Why would they have them at all? Elves, having seemingly endless life, must not get ill or catch diseases as Men might (no fatal tuberculosis, cancers or heart disease presumably), so why would they need healing powers? These skills must surely have been limited to healing battle wounds or maybe even just to healing Men?