Will I need another assessment if my impairment worsens and I need a wheelchair?

Hello @lilydj and welcome to the forum.

Short answer is you will probably need to be reassessed after recovering from the surgery, either because your condition has improved or as mentioned you end up in a wheelchair.

I do not envy your choice and not sure if I feel comfortable offering advice on whether or not to take the operation. I assume the pain you are in is because the spurs are trapping the nerves, and one of the dangers in having the operation is some form of paralysis?

Without doubt if the operation significantly reduces or removes the pain your quality of life will be far better, but this has to be balanced by what the likely results will be if things go wrong and how much you are prepared to risk for the improvement in your quality of life. Only you can make that decision, but it has to be based on a realistic understanding of the consequence if things do go wrong, along with the long term prognosis if you don't take the operation, ie will it likely worsen over time?

Do you know the type of surgery being recommended by the neurosurgeon? Interspinous spacers are less invasive, other types of operations in spinal fusion or decompression are more traditional.