Application/Addendum Issue

[candidate33]

How often do people submit an addendum clarifying something they said on an application? My medical history is very complicated and by trying not to go into too much depth on my applications, I ended up saying something that might seem inconsistent and/or a little odd to an adcomm. I really want to submit a one-sentence clarification but don't know if I should. UGH of course I made a mistake after reading over my apps 13434587 times....