I think one thing that people underestimate is that doctors induce damage every time you have an invasive procedure or take an RX drug.

In your case, baba, I see:
1) use of a fluoroquinolone drug implicated in PN

2) MRI for spine, and other things (more than one?) before the surgery? The spinal one was with contrast? Any MRIs with contrast may cause side effects. (doctors minimize this, but it happens).

3) Endoscopes? before your surgery (surgeries)? Endoscopes have been shown to be poorly cleaned and suspected of transmitting disease organisms in up to 30% of patients.
You can search Google for this data as it is mounting.

4) add to this any vaccines you may be getting on top of all the diagnostic work, that is a known nerve stressor.

5) then there are lifestyle stressors, which when changed are slow to help, so patience is needed for that. (going gluten free and/or eliminating other foods that cause intolerance like nightshades), and reducing/eliminating sugars and junk carbs.

6) fixing any nutrient deficiencies

7) avoid heating pads and hot tubs

And I am sure there are lots of other things like toxins, and autoimmune issues which develop in people over time. We cannot control the genetics of autoimmune liability, and only hope to avoid triggers, like vaccines and illnesses for that.

8) developing bone marrow disorders leads to PN, as well as cancer.