Vanessa, I would suggest that you remove the fish from the pond and put it in an isolation tank/container then treat the effected area with Melafix.

I have had wonderful results treating wounds etc, with it by initially pouring a teaspoonful of Melafix directly onto the wound.
If you have your fish in a container with just enough water to cover it. Wear a cotton glove and hold the fish up, so the abrasion/wound is out of the water and pour the Melafix directly onto the area.
Add more water to the container and treat it as directed, in the Melafix bottle instructions.
You should see a dramatic difference in the wound, in just a day or so. In a week it should be almost gone and you can return the fish to the pond. The Melafix stops any farther infection of the wound area.
"Horton"

Thanks Horton. I'll see how quickly I can get some Melafix. Problem with rural living, I have to mail order just about everything.
Vanessa

Vanessa, since it could be a time before you have Melafix at hand, you could treat the wound with a salt paste as described in a KoiVet article.
Again you should isolate your fish from the pond before treating.
Because you are going to use table salt be sure you have lots of water in the isolation container for the fish to swim in. Use water from your pond to fill the container, as it will keep the temperature the same.

Mix one part water with three parts table salt.
Wearing a cotton glove, lift the fish up out of the water enough to treat the wound.
Apply to the wound area with a small soft brush.
Repeat salt treatment in one week.
You should see a marked difference in the wound in about a week.
"Horton"

Well, whatdayaknow? Melafix at walmart. I'm saving the salt paste instructions just in case. Thanks, Horton!

Shouldn't the salt be "Pond Salt", i thought the iodine in the table salt was poisionus to fish?

It isn't being used to treat a pond Groundbeef, it is being used as an antiseptic on a specific wound.
I doubt KoiVet would suggest using table salt for this particular purpose, if it was going to create a problem.
With such a small amount of iodine in that much table salt, at a ratio of one part salt to three parts water,I very much doubt it is not going to cause any problems to the water quality.
But your question has validity, as table salt should not be used to treat a whole pond, because of it's iodine content.
Rock salt or water softener salt is used for that purpose.
That been said, there are differing opinions on the value of adding salt to pond water.
Disclaimer.
I make no claims, either way, to the merits of adding salt to a pond.
"Horton".

I might point out that a ratio of 1 part salt to 3 parts water is 25% iodized salt. That's pretty high.

And I only question because I sadly killed a fish early in my ponding career by "treating" a sick fish with idodized table salt.

Better safe than sorry.