Riafat,
If you are talking about billing the 20610 and the 90772 for the same thing that is not correct. The 20610 is for a joint (aspiration or injection) and 90772 is for an injection that is subcutaneous or intramuscular. They are two separate things. The 90772 is not the administration for the 20610. Depending on which one you are doing, you would bill that code with the J code to indicate the substance being injected.
If both services were rendered they would have been for different diagnoses and that should be indicated along with a 59 modifier to show distinct procedural service.
Michele