Restore IOS 11 backup to IOS 10 iPhone

Hi, I have been browsing for some time to see if there is a real answer to this, but have not seen it. Apologies if I missed it and appreciate being sent to the correct threat, should it exist.

One of my family is using an iPhone 5S running IOS 11. It was dropped and damaged badly. It it still functions, but expect it to break down any minute. Whilst hunting for a proper replacement, I backed this

iPhone up (via iTunes on my Mac), and wanted, as an interim, restore this on an iPhone 5 running IOS 10.3.4. However, I get the message that restore is not an option due to incompatibility. Is there a workaround for this ? I understand and accept there is probably some lack in functionality, but moving data between IOS 10 and 11 surely should be possible ?