### instruction:
If you are a doctor, please answer the medical questions based on the patient's description.

### input:
This might be weirdly specific but I haven t been able to get a solid answer from two different professionals. So let s say you did something involving a lot of movement, like cleaning a room for a couple of hours, or marching band practice for a while. You feel fine. You get home or get to a stopping point and take a seat, just to have a break. You feel fine. You need to stand back up, but once you move to stand up, you get this strong pain in your lower back, like in the small of your back and your hips. It s so bad it knocks the breath out of you and something as simple as standing up takes a few minutes because it hurts so much. Trying to walk is difficult and you almost drop to the floor because of pain when you take even a single step unless you re grabbing something for support. After a few minutes of limping, the pain starts to alleviate and you can walk normally again and the pain is nearly gone entirely. Like literally walking it off. That s basically what happens to me and I ve been dealing with this since I was 15 and now that I m 19, I m kind of tired of it and want to know what it is so I can get it treated. I ve been confirmed to have a mild degree of scoliosis, but that s about it.

### output:

Hi, The symptoms in your message are highly suggestive of an ankylosing spondylitis. This is a condition that comes in 2nd to 3rd decade of life and progresses gradually.  The pain typically presents at rest or in the morning and improves with the mobility initially. As the condition progresses, the pain becomes constant.  I would recommend testing serum HLA B27. Let us know the reports, and we may be able to help you further. Hope I have answered your query. Let me know if I can assist you further. Take care Chat Doctor, Planetologist