In the event you do have Piriformis Syndrome as part or all of your problem you could start treating this now by doing some simple stretches. Do an internet search and you will find these. Injections are not generally very helpful for this condition anyway. Sometimes a muscle relaxant can help keep the muscle from spasming (I take Baclofen) which is at the core of the problem. Piriformis syndrome will not appear on an x-ray or an MRI, however there is usually, another condition that sets off the Piriformis Syndrome and this may very well be identified by your diagnostic testing. In my case it is SI joint dysfunction. Best of luck to you with your quest for answers.