Cortisone works well if the problem is properly diagnosed and the injection technique is good. You have to diagnose the correct cause of the pain in order to know where to inject the cortisone. Even if you know the right tissue you want to treat, if you're technique sucks you won't get the cortisone to the right area. If you inject the cortisone around the area, but close to it, this gets the best result. If you inject directly into the tissue, the cortisone can weaken it and result in a rupture. That's likely what happened to Trickytiger.
Finally, even if the injection is a good one, if you don't eliminate the stress that caused the inflammation in the first place, the pain will come back and any relief you have from the cortisone will most likely be temporary.
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