I have a small patch of skin on the top of my foot on my fourth toe that is numb when i touch it but looks normal and there are no problems with moving the toe and the underside of the toe isn't numb either. why could this be?

It is possible it might be some scar tissue but the numb aspect of it suggests some form of nerve involvement. Might be a good idea to see the Skin Doctor (Dermatologist) first and then move on from there until the issue is resolved.

Symptoms are not typical of nerve damage but yet you have numbness. I would see a podiatrist and they can provide a complete evaluation and treatment if necessary. It could be as simple as your shoe irritating a nerve.