Sorry to hear that, Mike.
Two motor bike crashes in the 70s did some damage to my lower spine (as well as breaking both arms, smashing my front teeth which finally came out this year as well as cutting off my lower lip!). Physo, acupuncture, ibuprofen, lumbar support only ever gave a little relief, except that acupuncture was the best of them.
But the last 20 years have been office based and swivel chairs do my back in.
I bought one of these a couple of years ago---
https://www.amazon.co.uk/Office-Fitness-Exercise-Chair-Black/dp/B0050Q1SAAfor about 8 quid and am sitting on it now typing to you.
For the life of me I cannot find any anywhere near that price now! But the back is better that in a swivel chair.