Hi Ted,
Welcome. I respectfully disagree with the statement the reason you didn't obtain relief from the steroid injection proves you are "negative for that problem." Obviously I am not an expert and I don't know everything. Please don't take it that way. I just have not found that to be the case.
It's my opinion that because you have pain relief with the numbing agent they had the "right spot" ..... or your pain would not have ceased. However the steroid simply wasn't effective. .... Why? Sorry, I can't say for certain. Hopefully your treating medical professional will be able to answer that question.
I have had steroid injections too. The numbing agent relieved 99% of my pain, meaning they had the right spot..... and indeed I have SIJD. However the steroid was not effective in reducing my pain to any great degree.... the second time it actually made the pain worse once the "caine" wore off. It doesn't mean the diagnosis was wrong.... it was right on. It just meant the steroid was ineffective in my particular case. It happens.
Again I encourage you to discuss this with your Physician. He/She should have better answers for you. Hang in... a second injection may prove beneficial. I know many ppl that have had your same or very similar experience. In some instances a repeated injection was effective, in other situations it simply wasn't.
I wish you the best and hope you will share with us how you are doing. We'll look forward to hearing from you again.
Take Care,
~Tuck
Since the test was diagnostic it means it was negative for that problem. The pain went away as you said due to the lidocaine (which is short acting) and there was not inflammation so the cortisone didn't work.
mkh9