You may present as a freewill offering an ox or sheep that has a deformed or stunted limb, but it is not acceptable in fulfillment of a vow.

Exodus 35:29
So all the men and women of the Israelites whose hearts prompted them brought a freewill offering to the LORD for all the work that the LORD through Moses had commanded them to do.

Leviticus 21:18
No man who has any defect may approach--no man who is blind, lame, disfigured, or deformed;

Leviticus 22:22
You are not to present to the LORD any animal that is blind, injured, or maimed, or anything with a running sore, a festering rash, or a scab; you must not put any of these on the altar as an offering made by fire to the LORD.

Leviticus 22:24
You are not to present to the LORD an animal whose testicles are bruised, crushed, torn, or cut; you are not to sacrifice them in your land.

Either a bullock or a lamb that has any thing superfluous or lacking in his parts, that may you offer for a freewill offering; but for a vow it shall not be accepted.