Normal healthy horses rarely stands for any significant length of time with their hind limbs crossed. It is a vulnerable stance, and a horse usually quickly rights itself after a brief moment in this position. This reflexive response relies on long nerve tracts that run through the spinal cord to the brain and back to the muscles that control posture and limb placement.

This observation is commonly associated with a neurlogic deficit or spinal cord injury. It is also an uncommon stereotypical behavior. I have seen horses that crossed the hind limbs and a few that crossed the forelimbs. As with many stereotypical behaviors, it seems to intensify when the horse is anxious or distressed.