Dear,
Thank you for asking your query.

I'm sure by now you have learnt a lot about Ankylosing Spondilitis. In layman terms one can describe it as a condition affecting the joints of spine by bridging new bone between them. This differs it from flexibility hence the restricted range of motion. Over a period one has to go through anti inflammatory, disease modifying medications along with exercises and physiotherapy.

You must be having pain relapses once in a while. It may be related to your unaccustomed activity or posture. So I would advise you to take rest and improve posture till the pain subsides. The trick is not to do things that you fear would aggravate your symptoms, like excessive walking, working out, bending/leaning forward/backward or twisting back etc. You seem to have relief in forward bending which stretches your paraspinal muscles. That’s a good thing since it relieves muscle spasm.

The new bone formation if extends into canal carrying spinal cord may lead to stenosis. The pressure is taken by either the cord itself or the traversing or exiting spinal nerve. If you have symptoms like tingling numbness in one/both legs or pain radiating from behind your thighs up to toes, then lumbar canal stenosis is a possibility. Let me know if you have those.

Meanwhile, till you see your rheumatologist, refrain from any major physical activity, take adequate rest and use hot fomentation. Use medications under your physician’s guidance.

Hope this answer was informative. If you need more advice, I'm available for follow up.
Good day.

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