Tag Archives: tie back

Veterinary Nerding

Yesterday I left work early to go meet the vet for a couple of coggins tests and to scope white-nose face.  This is something that has been on the schedule for ages but has taken us a while to get done – typical communication glitches with answering services (“well, you said it wasn’t an emergency!”) and stuff has meant some delays.  Either way, it’s about time. 

So here’s the horse I call Noseface:

"topper" or "haagen dazs" or "Wheezy McSnoresalot"

He’s cute right? So cute we actually get a reasonable amount of mail about him, although he will not be available until after his surgery to repair his respiratory issues.  Scoping him yesterday was the first step in getting him fixed up – getting an idea of the extent of the problem so we can find out what kind of surgery is best (less expensive and faster recuperating laser surgery vs. the more invasive scalpel), and what kind of prognosis he has for recovery, etc.

As a warning, I sort of live for this stuff.  I find veterinary technology amazing, love playing with the equipment, and usually have a lot of fun assisting where necessary.  Even after my first euthanasia last fall, I stuck around to watch the dissection of the bad hoof, because I really wanted to get a good feel and understanding of what was going on.  While scoping a horse is hardly that invasive or oogy, I’d never watched it before and was very curious.

So after a couple hits of sedative and a steroid shot, out came the scope and we went in to see what was going on.

What we kind of already knew:  Topper has had previous tie back surgery.  You can see the scar on the left side of his throat, and through the scope you could see where the one flap had been pulled back.  However scar tissue in the area has impeded the airflow probably as much as the paralyzed flap did to begin with.

What we didn’t know:  The flap on his right side is also fully paralyzed.  So the total obstructed area of his windpipe is pretty large.  Like, if his airway is supposed to be the width of my clenched fist, the actual space he’s breathing through right now is about the size of one of my fingernails.

Additionally there is an area of his throat where there seems to be some pretty extreme muscle wasting.  Which led the vet and I to theorize about possible nerve damage to the area from the original surgery – this is especially noticeable on his right side – which is not the side that had the initial tie back (and where it’s actually pretty rare to encounter this problem).

So, for nerdery’s sake, here’s some images to try and describe what we saw.  Be warned that people who are walking by may not understand that these are pictures of a horse’s larynx, as they look somewhat similar to, um, something else which shall remain nameless.

From the Merck Veterinary Manual Online

Above is a horse whose left flap (the right when looking at the picture) is paralyzed (I use the word flap, they are actually called arytenoids but that’s a big word).  Usually, if anything is paralyzed or problematic, it is on the horse’s left side.  Apparently this is due to the odd configuration of the major nerve running through that area, which is situated in a different way than the left one and making it more prone to damage.  At least, if I read this page correctly (and I do recommend going to that link – they do laryngeal scoping while galloping horses under saddle, and have lots of neat information).

Here’s another image from the above link – a normal larynx vs. one with paralysis on the left (the abnormal pic is zoomed in quite a bit from the normal pic, if you’re wondering):

Normal vs. Left Side Paralysis

Now, imagine the above picture with the OTHER flap also in the same obstructive position.  If anything, in Topper, that right flap is almost more in the way as it wasn’t pulled/tied back in his previous surgery.  If I had to come up with a number I would say about 85% of his airway is obstructed just by the arytenoids.  (I know I’m botching this all up, not being up on my technical wording, but there you go).

In addition, Topper Wheezerface has some scar tissue and stuff in there further obstructing things.  As well as lymphoid hyperplasia (I had to have the vet spell that.  heh).  Basically, if I’m reading the Merck site properly, this is essentially inflammation of the scattered lymphoid follicles (instead of a mass of centrally located lymphoid tissue like people have with tonsils, horses have these follicles essentially scattered about their throat), a sort of immune system “event.”  Apparently it’s relatively normal in young horses, but in a 5 year old maybe not so much.  But as it might represent a response to irritation, etc, it would make sense if it was contributing to the worsening in Topper’s symptoms, as it’s spring, it’s suddenly gotten quite hot, and there’s a lot of allergens and irritants in the air right now.  Steroid shots can help with this, but it’s pretty much the most minor of his problems.

I’ve been trying to find pictures of a post-op tie back operation, and one that has developed scar tissue, but no luck there. 

Either way the next step is surgical consult, and then actually getting it done.  We should be able to help him out tons with surgery, the only real question is the level of improvement we’ll get, and what his future as a riding horse holds.

This is definitely the kind of thing that those interested in purchasing horses off the track need to be aware of.  As tie back surgery is relatively common, later complications from that surgery can also be somewhat common.  If you’re going to look at a horse at the track, always remember to ask about any breathing issues, and if you are getting a prepurchase veterinary exam, make sure the vet is paying attention to that area as well (if you are really serious about that prepurchase go ahead and spring for a quick scope).  Make sure to find out if the horse has had prior tie back surgery, how long ago it was, and if he’s had any other problems since.  Look up the horse’s race records and read the comments.  Often, horses we’ve run into with breathing issues are described as having “stopped” at some point in their last few races.  That said, the vast majority of amateur owners looking for pleasure horses and low level show horses don’t need to worry too much about this stuff.  Most horses with past tie back are pretty much fine for everything you’d want to do, until you start talking about high level competition, or disciplines where breathing noise is considered an “unsoundness.”  It’s just good to know – information to file away in case something comes up later.

This is also where it pays to pay attention to the racing industry a bit.  There’s one race owner in particular who goes ahead and gets throat surgery done pretty much on every horse in the operation, whether they need it or not.  This is the myectomy, not the tie-back surgery, which is done for different reasons (the epiglottis being entrapped by the soft palate – here’s an article from the Thoroughbred Times that goes into more detail).  The reason myectomy is important?  A lot of the effects are unknown, and there seeems to be evidence that it can sometimes result in problems in others parts of the upper respiratory tract. 

Either way, it pays to look over a horse’s racing history and ask these questions when you’re going to look.  None of the above mentioned stuff would stop me from buying a horse, but it’s just really good stuff to be aware of.  Most of us are not going to be pushing a horse to the limits of his physical capability, so even some breathing obstructions are unlikely to become a problem for us.  But it’s always good to know as much about your horse’s history as possible.

As a quick side note, dear friend of CANTER Mid-Atlantic Lynn Reardon, of LOPE in Texas, got the spotlight in the New York Times’s “Rail Blog” – go check it out and give her a little comment of support 🙂  And if you haven’t already, run, don’t walk, to your neighborhood bookseller and get a copy of her “Beyond The Homestretch.”

In other tidbits, keep your fingers crossed – two of our harder to place mares may be going to a new home this weekend.  If this works out it will be like hitting the lottery! 

Also, please continue to vote for us daily at the Pepsi Refresh Project.  I know it’s sort of a pain but it’s a super easy way to help us help more horses.  You also get ten votes daily and there are plenty of other worthy projects on there (my favorites?  Helping hospice patients keep their pets, Baltimore after-school projects, and a project to convert boring old lawns into usable and productive gardens)