Problems throughout spine : cervical, thoracic and lumbar

I have already had an ACDF of C3/4 and C4/5 done about 4 and a half years ago.
I have also had a lumbar fusion of L4/5 for grade 2 spondylolisthesis done 7 years ago.

I saw my neurosurgeon yesterday, and there are no plans to do surgery in the near future, which is good.
However, some of the things I was told during the appointment have left me with some concerns.

He showed me where the two levels above my lumbar fusion have herniated and are compressing nerves. I am recognising some of the symptoms I am getting from before. My right leg pain is the worst side, but the left does have pain sometimes. The pain is often on the outside of my hip, running down the front of my thigh to the kneed. Some times it continues from the outside of my knee to the shin. The neurosurgeon showed me the two disc herniations and explained that with a surgery he would have to fuse both these levels. He said he would have to extend the fusion I already have to include these two other levels. He said it would be an invasive surgery. My husband, who was at the appointment with me, assumed that the surgeon would have to remove the rods I already have to extend the titanium hardware. We have discussed how this would be possible if there is bone grown all around it. We wondered if this is what the surgeon meant when he said it would be an invasive surgery. He is afraid that if he included these two levels in the fusion, the strain on other levels would make it likely for them to need surgery later and a domino effect to go right up my spine. I think this is because I have so much degneration throughout my spine will all thin, black discs and many osteophytes.

Looking at the 3 worst thoracic discs in a line that are herniated and compressing the cord but only just onto the actual central cord. The surgeon said that to do surgery on these levels would prove difficult because of the problems with accessing the discs. He said he would have to deflate a lung or remove a rib (or possibly both, I’m not sure). He said that it would be a very long and painful recovery and I would be in much worse pain that I am at the moment.

He then looked at my neck where the two levels below those fused have almost completely lost the discs. There are very large osteophytes and he feels the vertebrae will fuse themselves. I asked if this would be a good thing or a bad thing. He said that if they fused if a good position it would be a good thing because it would stabilise the vertebrae which would stop more osteophytes growing. He is happy that there is just enough room for the spinal fluid to flow around the cord.

I asked him what the prognosis was for these different levels and he said he couldn’t say. I realise that he can’t be sure, but I am wondering how likely it is that I may need more surgery in the future. I feel rather like a ticking time bomb, and wish I could just forget about my spine. Pain is a strong reminder that all is not well!

I would really value your opinion on this Dr Corenman. I am in the UK where we wait a long time for our appointments and then they are very short, so not enough time to ask all the questions we have.