I've had like over 20 blocks, the ones i had for my left arm never worked, i think i had them too far after i initially got hurt... when i broke my foot i had a few lumbar blocks right away and they did help with my swelling and keep the pain from getting super intense... and when i started to spread to my right arm i got them right away for that too... just cuz i knew they needed to be done like asap. its pretty much a hit or miss i think with blocks... they've never gotten rid of my pain or other symptoms... just kinda kept them from getting super bad when done early enough.