Well, I've finally gotten the nessissary materials and I've made one up for my son.
According to him, the coil does indeed work, to an extent. It takes a way some of the pain so he can now actually move around and shift possitions on his bed. I'm very glad to hear that. However, just by the expression on his face, I can tell that he's still in a lot of pain. In addition to that, he's unable to wear the coil when trying to sleep since he claims it's far too uncomfortable.
Unfortunately, he's been in pain for over two year now, and due to not being able to work out, he's gained a lot of weight. (which I find odd, considering he rarely even eats one meal a day, tending to just snack on something) The coil seems to dig into him and leave impressions on his skin, even when I loosen it up. But I suppose that's not too big of a problem. The fact is, it's working to help ease some of his pain. Thank you very much for recommending this. I hope that if he continues to use it, it will take away even more of his pain so he can actually get up and walk again.
Would using more than one coil at a time have a cumulative effect on his body, or would that not help him any? I'd gladly make him several more if wearing more than one at a time would ease his pain even more.