Q. My 20-year-old off-track Thoroughbred was lying down when I went to feed and turn him out this morning. When I brought his breakfast into his stall, he reached around and started scratching one of his hind legs with his teeth, still lying down. Then he grabbed his hind fetlock with his teeth and started yanking his leg around … I’ve never seen him do anything like that. I don’t think it’s pain-related; his veterinarian was just out for a wellness check the previous day, he ate all his breakfast that morning, and he ran around the paddock like he always does when I turned him out. Why might a horse to do something like that?

—Adam, via e-mail

A. If you have never seen it before and not again since, one possible explanation for a combination of leg scratching and dragging would be simply what humans know as the limb “falling asleep.” This situation results from nerve compression, which can result in temporarily ­numbness, weakness, and/or paralysis, as well as that momentary peculiar sensation and, in some cases, pain. So the scratching could have been to relieve the discomfort, while the yanking of the limb around may have been a natural frustration-driven response to temporary limb paralysis.

If this happens repeatedly or frequently, I would recommend discussing it with your veterinarian, who might want to do a more detailed neurologic exam