An asana question

I do legs circles to help loosen up the pelvic region, as part of my sequence. I do this by laying flat on my back, legs pointed up to the sky, and rotate them 30 times in each direction. When doing this there is one tiny part in the motion that is not completely smooth but I have never had a major trauma in my pelvis that I now of. It is not uncomfortable, nor any type of pain after. Kind of hard to descibe the glitch that happens when doing this. I could say it feels like a little pop, which it kind of does, but its not like it pops out of place. any insight on how to smooth this out?
thanks
brother Neil

It is normal. This is the way humans are designed:) me, my friend, all my students pop during hip rotation, and it will never go smooth.

Thanks, did not know if there was some inner/outer spiral issues going on.