Boxer mix skin condition

Question
We rescued a boxer mix about 3-4 months ago, he had been hit by a car with severe damage to his hind legs and feet, since we brought him home we have noticed that he had progressively started to lose his hair.  I brought him to the vet and they ran test to determine if it were mange or not - it came back negative.  she had given us some vitamins (oil to put in food) and a medicated bath. It has cleared up some, but where he and our other dog play he seems to lose his hair.  All around his neck and back he itches and has a lot of "flakes" or dry skin. Is there any kind of powder or something else to help him not itch so much?  Also, is there a vitamin (oil) that can be purchased in a retail store or online that is less expensive that will work just as well?
Thank you for your time,
Paula

Answer
Any time a dog is injured and there is tissue repair, they will lose hair and their skin condition will deteriorate.  When the healing is complete, the skin will again get nutrition.  YOu can bathe the dog frequently to remove the dead skin scale and hairs and you can use Omega3 fatty acids in the food to help the skin and coat regrow.