So it seems losing weight has left me with a bony butt. So bony that I have a large, increasingly painful, rock hard lump near my tailbone.

It's not a cyst, and an MRI indicates that it is not a bone problem. It is just swollen soft tissue. Naturally the doctor won't discuss it over the phone, and my next appointment is almost 4 weeks away.

It's hurt since December, and it's getting worse even though I use a coccyx cushion.

Has anyone else had this problem since losing weight, and if so, what made it go away (if it went away)?

It's painful to the point I'm going to have to cancel a vacation if it doesn't get better. I can't sit on a plane for 1 hour, let alone 9. It's even limiting what I can do in the gym because lying down on it feels like murder.

I'm so sorry to hear that. I wish I had more to share. My father had a similar problem after some health complucations and used a memory foam pad to sit on. He then gained some weight back and things returned to normal.

Sitting on a pillow or cushion sounds like a good idea.

Something that might help is exercising the glut. muscles. If those muscles can get bigger, maybe they'll help pad the area.

Good luck! If you find something that helps, let us know!

I know you said it's not a cyst, but it sure sounds like a pilonidal cyst - its location, that level of pain... Can you go to your primary doctor? (Not sure if you meant bariatric surgeon when you said "doctor")

Thanks. A colo-rectal surgeon said it's not a cyst, after a doctor referred me to him to have the "cyst" removed.

In the mid 90's I had the same problem. I went from 215 to 145 pounds in a short period of time. Mine was at the base of my tailbone and got so large it finally burst (in the middle of class and I was wearing white shorts O_o). Since that time it occasionally flares up, but nothing like it was. I have never had it looked at by a doctor or surgeon, but I do remember the pain very, very clearly. Sorry you have to deal with this, I would be very upset if the doctor made me wait 4 weeks to talk to me.