Brief Answer:
would cause abnormal sensations and possibly affect organ function

Detailed Answer:
Hi,

The nerves in the back supply specific areas of the skin and organs in an area. EG the nerves in the lower spine (lumbar area) exit the spinal cord and then exit the back to supply the lower limbs and nerves are also sent to help with bladder and bowel function

Therefore shingles in the spine would therefore affect supply to these areas. It presents in the areas of the body that are supplied by the specific nerves.

So if there is shingles in the thoracic spine, there would be issues (such as numbness, tingling,burning, sticking/sharp pain, weakness) of the skin in the thorax/chest and also issues with the organs in the abdomen since these nerves supply these organs (stomach, liver etc)

If there is a infection involving the lumbar area then there would be tingling/numbness/burning etc in the skin of the lower limb as well as possible problems controlling the bladder or bowel.

If there are any other problems with the spine such as arthritis or stenosis (narrowing), then this would also present in this way. The way to tell the difference would be the changes on imaging (x ray or MRI).

Summary- would depend on the part of the spine involved

In general would cause tingling or numbness or sticking or abnormal pain or burning etc in the area that the nerve supplies

May also affect the organs that the particular nerve supplies

I hope this helps, feel free to ask any other questions

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