I have a chocolate girl who has something strange going on with her legs. There is a rectangular patch of hair missing on the outside of the bottom portion of her leg below the knee. I seen it happen to her once before. Its as if the hair was scraped off with a razor. No redness or bleeding just a bald patch. She has good coat and skin and is not itchy. This is so strange. Could it be anything other than roughhousing?
Is she by any chance in whelp? Do you have a dog door or does her kennel run have a dog door? I had a bitch who had to adjust her entry through the dog door as her belly dropped and she scraped the front of her rear legs as she ducked down to get through and back up, if that makes sense at all. I couldn't figure it out until I watched her manuever through one day and from then on I took her out on all potty breaks. Since then, we've installed an xl door and no more scraping!
I think you may have something here with the doggie door idea. The bald spot is about 2 inches long and 1 inch wide. Nowhere else on her body. Just that one scrape. It could have very well been the doggie door. Thank you!