Hi Marley, I found this great article on windpuffs that I think will help answer your question. Many times these are just cosmetic and do not require treatment. However, when treatment is needed, some suggestions are:
- Ice and bandaging
- Topical anti-inflammatory medication such as Surpass (diclofenac sodium)
- If the problem does not respond to rest and wrapping or support boots, you can inject windpuffs with steroids and hyaluronic acid, similar to how you'd inject a joint, trying to reestablish a normal environment in the sheath and, ideally, preserve tendon function.
Many windpuffs respond favorably to ice or some bandage support between competitions and don't need medication. It's different for every horse, and the most important thing to do is watch them for changes in size and symmetry among the affected legs, and observe whether your horse is uncomfortable. Discomfort and/or heat and swelling could be a sign of acute injury, so call your veterinarian in these scenarios.
Here's the article with a lot more info and context: http://www.thehorse.com/articles/22897/windpuffs-in-horses