I have a 6yr old mare that when she trots sometimes holds up her rt back leg for about 5 sec. what causes this

Question

it is almost like she is a male dog urinating. very strange but it does not seem to hurt her

Answer 1

It's more common in miniatures, but she could have a locking patella.

In order to sleep standing up, horses can use a ligament in their stifle (which corresponds to the human knee) to lock their legs in place without thinking about it.  In some horses, this ligament can get stuck over a bump on the joint and lock up their leg without them intending too.

THe best treatment is conditioning, which I've heard helps, but other than that, I don't think there's a good treatment for it.  Usually it doesn't hurt, but may make her awkward to ride.  Good luck.

Here's a website to look at:

http://thehorsedoctor.blogspot.com/2005/...

Edit:  Stringhalt, IIRC, happens on every stride, and is more of an exaggerated movement with a pause than an occasional 5 second event.  The locking patella (also called locking stifle) is more of an isolated event and lasts more like 5 seconds, across several strides.

Answer 2

Yup, that was my thought Stringhalt. It has to do with the tendons or hock action in the leg where they lift the leg very high and a hesitation.  We have a horse at the barn that has that also...in his left rear.  It does not appear to have any negative effects on him..he is sound.

Answer 3

could be string halt

Answer 4

get the vet to come out and look at her, something might be painful for her

even if you dont think it hurts her you should make absolutely sure