We Have An Answer
Last Wednesday I braved driving over Snoqualmie Pass with horse in tow to get a second vet opinion to hopefully find out what was going on with Prevost's leg. Thank goodness I have some great friends that met me there and came along for support! I couldn't do it without you! We met Dr. Schneider (Dr. S) at the Emerald Downs vet clinic in Auburn, WA, barely on time, our drive over the pass was slow and careful, weather was not ideal! (Ahem, 20mph!!!!!!!! - Never again will I do this unless emergency!)
We started with a lameness exam, trotting up and down the pavement and doing a few flexion tests. Dr. S was able to identify very mild lameness on the right front. There is no head bob to this lameness, but he was able to hear how the foot falls were unevenly weighted. Prevost was not weighting the right equal to his left, with putting more weight into his left front. Flexion tests did not make the lameness better or worse.
At this point, there is was no swelling in that leg, I had wrapped them for the trailer ride and they were nice and tight. Dr. S was hoping to be able to see what the swelling looks like, so I suggested we just go lunge Prevost for 10 minutes or so. So that's what we did. While we lunged in the rain on the black top, Dr. S thought the lameness was getting a little worse - I saw this too.
After lunging and generating the swelling, Dr. S was pretty positive this was swelling in the Carpal Canal. The carpal canal is a sheath that protects and holds several tendons at the back of the knee. For some reason it was being irritated and swelling up with movement. We also noted the enlarged vein running down over the inside of the knee. So up to this point everything was accurate as to what I would get at home, thank goodness, because you know when you take your horse to a lameness vet they don't swell up and won't show the symptoms! lol
So next we went back in side and Dr. S looked at the X-rays I had done back in August. All of those Xrays focused on the lower leg. Dr. S wanted to take a look at the knee so here we go prepping for a few more x-rays a little higher up.
The x-rays found a bone spike on the back of the right front knee. Prominent enough that Dr. S was pretty positive that this was the issue. He believed the bone spike was rubbing on the carpal canal and even possibly tendons! He also took x-rays of the left front for comparison. Left front also had mild bone formation... I was worried about this but Dr. S said, knock on wood, he has never seen this type of modelling of the growth plates to affect both legs... Good news I guess?
We next prepped for ultra sound to see if we could notice irritation of any tendons or ligaments. The ultra sound came back clear, but Dr. S made sure to tell me ultrasounds are not 100% and only an MRI would be able to look at the area behind the knee more accurately. As some may know, and MRI runs $1800, money I don't have to spend and since Dr. S found the bone spike in x-ray, I wasn't too concerned we needed the MRI.
Next we decided to do some blocking just to make positive it was the carpal canal swelling causing lameness. First we nerve blocked the right front hoof, just to make sure it wasn't something lower before just jumping up the leg. Let the numbness set in, go for a trot out, and no difference in gait or lameness. So we got back inside and Dr. S starts prepping to inject the carpal canal.
This was kinda cool part. The carpal canal is not an easy spot to pin point, so to make sure we got the needle in the right place, he first injected with just saline solution. He then called me over to feel the leg. "Does this feel like the swelling you would normally feel after riding?" OMG yes, even worse! So he then filled another syringe with the blocking agent to numb things up.
After about 30 minutes we took him back out for trot out on the pavement. HE WAS NOT LAME!!!! So this confirmed it, the carpal canal swelling was causing him discomfort. Finally have an answer!
Dr. Schneider considered this a performance limiting injury, not a performance ending, which is good. He suggested a few types of treatment. First one is to rest Prevost for tendon injury, on stall rest for 6 months and see if that heals it. Second would be to inject steroids into the sheath and see if that limits the swelling, or third, preform surgery to remove bone spike (recovery of 1 month surprisingly) and combine with 6 month stall rest to heal from surgery and allow possible damaged tendons to heal.
Dr. Schneider said he sees things like this on the track with the thoroughbreds quite a bit and believes the main cause of lameness is the bone spike. He said if we do surgery, prognosis is very good for him to return to endurance riding.
So as much as I am happy to have an answer, I sure wish I would have figured this out last August when we first started investigating. It is what it is, and at this point it will be over a year that Prevost has had off from any work. I am now trying to weigh the idea of paying for surgery and how that will affect my home life. I always said I would never pay for surgery on any of my horses, but because this one seems to have a good chance of full recovery, I feel its not worth just turning Prevost out for the rest of his life.
It will take me a while to make the decision, but right now my lovely husband is working on building a stall door and lining the shelter with rubber mats in preparation of starting his 6 months stall rest. I am prepping myself for the intensive care that comes with having a horse on stall rest and making sure I have several ideas lined up to keep him occupied. He has some stereotypes that worry me once he's put in the stall, so I am trying to be ready to help him curve the nerve. Self Mutilation is what he does when confined, that's another post entirely, but look it up if you want to know more about it. Anyways, I will keep the blog updated when things start to happen! :)