<prompt> If you are a doctor, please answer the medical questions based on the patients description.I am 25years unmarried woman. I have got back pain since 1 year. pain i feel more at night and it radiates to left lower extremities. I consult with ortho doctor n he ask me to do xray so i did it. and it was written sclerosis of sacro illiac joint. do i need to worry about this? what actually i need to do. please suggest me.  <response>: Hi welcome to Chat Doctor forum. Thanks for asking a question to Chat Doctor. F. You are 25 years, unmarried, got back pain since 1 year. More at night, radiates to left lower extremities. It is diagnosed as sclerosis of sacroiliac joint. It is a sort of arthritis, followed by fusion of the bones. There is no treatment, but can have a maintenance therapy. Includes neurotrophic injections, Gabapentin, besides other Chat Doctor. 