@magnus34, I have been searching for relief of a SI joint pain in one buttock; a dull deep pain that has kept me from walking around the block with my dog, at it's worst.
I sought SI joint orthopedic specialist in my area; I had to have a 1st injection of lidocaine, that was of little help, followed by a steroidal injection...which was negative help also. Frustrated, I started doing PT exercises and they have helped me to the point of 50-70% improvement. But I have to be vigilant (and have only been doing PT for 15 days).
I've read and watched a lot of chiropractors and what they say they can do and what you should avoid from them, in terms of "manipulating" the SI joint. It's a joint, they say, that needs little manipulation. I had a hip replaced on that side 10 years ago and wonder if that can create an issue. The orthopedic offices say if I want to MRI my lower lumbar, they might be able to find the cause of the pain...