You may be able to deduct part of the cost of the shoes, if the special shoes cost more than a similar shoe that would not accept the orthotic device.
The best guidance on this issue comes from IRS Pub. 502 Medical and Dental
Expenses:
"You can't include in medical expenses the cost of an item
ordinarily used for personal, living, or family purposes unless it is used primarily to prevent or alleviate a physical or
mental defect or illness. For example, the cost of a toothbrush and toothpaste is a nondeductible personal expense.
In order to accommodate an individual with a physical
defect, you may have to purchase an item ordinarily used
as a personal, living, or family item in a special form. You
can include the excess of the cost of the item in a special
form over the cost of the item in normal form as a medical
expense."
