How so? As far as I know, the toes have the same names as the fingers on the hands. So on your feet, too: thumb, index finger, middle finger, ring finger, little finger. Yes, it's not very logical with the index finger, because they certainly can't point at anything. You just can't do the same thing with your toes that you can do with your fingers when you point at something. All other finger names do not cause this discrepancy.

By the way, in medicine, as far as I know, the numbering of fingers is simply used: 1-thumb … 5-little finger

How so? As far as I know, the toes have the same names as the fingers on the hands. So on your feet, too: thumb, index finger, middle finger, ring finger, little finger. Yes, it's not very logical with the index finger, because they certainly can't point at anything. You just can't do the same thing with your toes that you can do with your fingers when you point at something. All other finger names do not cause this discrepancy.

By the way, in medicine, as far as I know, the numbering of fingers is simply used: 1-thumb … 5-little finger