Angie Harmon's doctor had an interesting explanation for the actress' back pain: she has no butt.

Harmon explained her doctor's diagnosis on "Conan."

"I was told that you had a back injury recently and I was worried about you," the late night host told the actress.

"I recently got an injection…into the spine…I mean they go in there!" Harmon revealed.

"Oh my God! That's serious," Conan responded when Harmon showed an X-ray of her spine.

Harmon said that her doctor told her, "I don’t see a butt" and she "just went, 'Really, you’re looking at that and all you see is I have no butt?"

"The doctor said the problem you have with your back is you have no butt?" Conan laughed.

"I used to but after 3 children in life it just went..."