
Scratches appear in the heels and back pastern area — which is probably why it is also called “greasy heel”. It is usually a bacterial infection, caused by Dermatophilus congolensis and Staphylococcus spp but sometimes can be caused by fungal organisms. It appears more often on white legs.
What causes Scratches to appear?
Scratches can occur when the skin is irritated or when a horse is kept in a muddy environment. In Freedom’s case, it started after he abscessed on his left hind (the one with a white sock). I bandaged the pastern area of his leg and put a hoof boot on but the boot/vet wrap rubbed and left his skin chapped. Add some mud to the equation, and we got mud fever.
Scratches appear as scabby lesions which can look like dried on mud. If you try to get them off, they reveal a red, oozing sore that is painful to the touch. As it progresses, the hair on the leg becomes crusty and matted and the sores may ooze.
The area may also become hot and swollen and in some cases, your horse is lame. Freedom showed some slight swelling in his pastern/ankle area although thankfully he was never lame.
How do you treat it?

One of the first things to do is to clean the area using an anti-microbrial wash. Your goal is to remove the scabs and it is often necessary to soak the affected area to soften them — otherwise removing them is quite painful. It’s a good idea to wear gloves and to sweep up and remove any of the scabs as it is possible to transfer the infection to other horses.
Once the affected area is clean, you want to soak in Betadine for up 10 minutes.
The first time I have the leg cleaned I also dry it and clip the entire area to remove any hair that could get matted.
Once the leg is clean and dry, you should apply a hydro-cortisone treatment such as Hydro-plus. Your vet may also prescribe antibiotics (my horse had a full course). I also used a topical anti-fungal cream from Zephyr’s Garden.
I soaked it every day in Betadine to help keep it clean — because this is caused by moisture, you don’t want to wrap the leg.
Although I’d tried some “home remedies” such as diaper ointment and tea-tree oil, my vet said that it was best to use a hydro-cortisone cream once the scratches appear; diaper ointment can be used as a preventative to help protect sensitive legs.