Brief Answer:
Simple causes may explain it.

Detailed Answer:
Hello and welcome to Ask a Doctor" service.

I have read your query.

The heels may get numb on occasions because of prolonged standing up (after a long day for example).

Certain body positions may affect the blood flow to the legs that also may cause numbness.

Small bone spurs of the heels also may contribute to such symptoms.

All these possible causes are of concern and don't point towards any neurological condition.

So, I think you should not be worried much more than necessary.

Hope you found the answer helpful.

Let me know if I can assist you further.

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