what kind of doctor would you see for sacrum joint problems? Just a Chiropractor or a more specified doctor?

you see your family doctor and go from their

orthopedic specialist or even physical therapist that can teach one proper mechanics and proper exercises. I have issue with L4 and below, chiropractor only made things worse, frigging asshole. You got bone issue, seek an ortho, one that specializes in that particular area. My shoulder/ankle/knee guy won't go near my back. My back guy won't go near my hip, even though at one time it was his specialty. Sucks to have to have so many but that is just how it works now a days.

An orthopedic doctor or spine specialist may be able to help you, but you could also consult with a rheumatologist. A chiropractor is not always helpful when you have joint issues, and in some cases they can make the situation much worse if they irritate the pre-existing condition through manipulation. Avoid a chiropractor until you get some x-rays or an MRI done and are cleared by a orthopedist or rheumatologist.

Never a chiropractor. They are total quacks.

I would start with my GP then if indicated, I would get referral to an orthopedic specialist. Physical therapy may be in order too once a proper diagnosis has been made.