Is It Safe To Get Trigger Point Injections On Buttock Instead Of ST Joint?

Are trigger point injections safe in pregnancy? I have severe sciatica due to a degenerative joint at L5&S1. My disc is also bulging. I am seeing a chiropractor but the pain in my right buttock is so severe at times I cannot stand up. I've had trigger point injections in my shoulder blade before and it was simple. Can I just get trigger point injections in my buttock and not the SI joint that requires x-ray? Would it be safe?