No not isolated. I started using those "expandable" leg rings 3 years ago and I have constantly had hens limping, or swollen or the leg grown into the ring. They are horrid.
They should make sure people know only to use them on broilers or something that does not grow or live long.
I saw a hen limping this morning and her band looked fine but I know enough now to know that is it. So I tried to turn her band and sure enough it was stuck. So I tried to stretch it out so there would be more room to see if maybe I should have been doing that in the beginning. But it just broke into pieces. Thankfully it is about the last of those rings I have left.
In the beginning if they were too loose the hens would peck them off. So its just not a good product for hens you will keep a year or more.
I am using multi colored zip ties now. That way I date my purchase purchase and can identify each bird if I want. Blue for one date, Red for another, left or right leg or no band, or long or short tail on the zip, or two zips, but I seldom use 2 zips.
The real tiny ones for electronics are best but hard to find multicolored batches, so a little bigger wire bundlers are ok.
Or one color for each bird all on right leg for one date, and all on the other leg for another date. Which ever you prefer.
Some say not to use zips because they can get caught. I have never got a hen caught and I leave them real loose so that they have room to grow and they never get tight and they don't get dirt stuck behind them and nothing gets caught. The hens don't peck them for long.
Haven't had a problem with any bird I have purchased with zips or the ones I have put on over the years. Except one I put on too tight that I could see was as she grew was getting tight on a big Gold star so I cut it off and put on a new one.