pat.......
First of all, if the back pain is making your life difficult and unpleasant compared to the pain from your other joints, then I would certainly go for the operation.
The results of this operation are at best good and at worst, satisfactory for the patient.
Go for a Neurosurgeon rather than an Orthopaedic surgeon.....in my opinion.
Spire Hospitals have a good reputation and of course the NHS has private beds. I wouldn't have thought that Intensive Care would be an issue with your type of operation but even the simplest of operation might need intensive care for many reasons.
The choice of hospital is yours my love but I don't consider it a big deal.