I also wanted to ask if you definitely need the surgery. I'm hoping that perhaps with weight loss and therapy maybe the back pain can resolve itself?

I knew someone who ate the post-gastric diet and successfully lost enough weight that he did not need weight loss surgery.

Sensitivity to salicylate can actually cause pain. Not many medics seem to know this and keep prescribing higher doses. I would hope this is not you because you need pain relief. There are aspirin free pain relievers available on prescription. Little regard is given to salicylate being in foods, its the means many plants protect themselves from molds and mildews. Most household cleaning and personal hygiene products contain the stuff too. Please take a look at SalicylateSensitivity.com. There are other sites which relate to it, Asprin and salicylate sensitivity, "Food can make you ill", looks at other possible toxic reactions people can have to "foods". SS can be implicated in Autism and many other health problems. The principal food lists were devised by an Australian dietitian, Ann Swain and colleagues many years ago. Increasingly products are being made without the stuff.

For me I react to even low levels in food, and perfumes/smells in general. After a week when a teenage granddaughter stayed I was on crutches with joint pain. It all resolved quite quickly drinking plenty of water and going extremely low in the stuff. Avoiding it as much as I can I'm pain free. Went out to look at a camper van, to take some of my life back and had to say, I'll come back masked up to take it for a test drive! There are air cleaners and bicarb which will take the smell out of it for me if I want it. I was loosing the ability to think.