Hi Catriona
I developed chronic bowel problems after epidural steroid injections, which includes muscle damage, colitis and scarring (granulomas). I was diagnosed as having total spine arachnoiditis 7 years later! From the literature I've read, it does appear that many sufferers get bowel and bladder problems.
Sorry not to have better news - if you need a good gastric specialist in the UK, let me know.
Best Wishes Helen