when coding SI joint injections without guidance, the book instructs you to use 20552 & 20553. I am not understanding how the SI JOINT can be coded with a code which clearly states trigger point "muscle" . The SI is a joint and not a muscle. I have been told by employer that the correct coding is 20610. Could someone please help me understand which code is used for a patient who has received SI joint injections without guidance.

Thank you, in advance, for any help with this matter.