I had kidner procedure and after 6 months on the same place i have an even bigger bone sticking out now,it doesnt hurt but its huge...x rays says its not an acessory navicular anymore but its still huge bone and sticking out...is that normal oor??

If you're concerned ask your surgeon who removed this unnecessary, extra bone to recheck your foot and explain the apparent deformity.

Good question. Sounds like you had the congenital accessory bone removed and developed a post operative heterotopic ossification. One doesn’t re-develop a congenital accessory bone (os naviculare in your case). Since as u stated the new bone formation is not symptomatic, it should be ignored by you. An ossification like this should not be removed unless it’s symptomatic and only when it’s matured