knee injection

If a patient was sent as a referral for knee pain and the physician ended up doing an injection to the knee, would you code just the injection or the e/m and the injection?

Knee injection

Since the pt was sent to you on a referral for knee pain not for the injection I would code the appropriate level of e/m with modifier 25 appended and then code the procedure as long as the doctor did the required components to meet an e/m code requirements.

knee injection

Thank you. So, is the only other time you can use an e/m with a procedure? I know that you can do this on an established patient if the physician does an e/m that is separate from the procedure. Do you know of a written rule that refers to this?