Figuring out a NQR horse is like peeling an onion. Buckle up! (another good update post #32 MFM diagnosis)

[Junebuggie]

I’ve learned so much from these threads, especially over the last year as I’ve had setback after setback with my wonderful mare, So to start: 10 yo KWPN I’ve had her since she was five. Last summer we earned our bronze medal, She is my love, and I absolutely adore her. Late last summer, she also developed a weird swelling in her left front fetlock, no heat, no soreness. Through the fall she was perfectly sound but every once in awhile, she would take a funny step, changing direction. As we got to December, this got worse, so I contacted my local vet who blocked to her fetlock and suggested an MRI. MRI revealed synovial herniation, slight suspensory desmitis. Surgeon recommended surgery. He removed a fairly large ’ ganglion cyst’ and was pretty sure that was the cause of the front left lameness. She came home and started rehab…hand walking to tack walking etc. She handled it all like the princess she is and she was perfect.

Fast forward to March, 2 months out from surgery, the sport horse vet pays a visit to take a look (it’s so much easier when they come to you:)). She looks awful, still completely lame on the left front. Decide to do PRP on the fetlock and see if that can provide some relief. It doesn’t help, so we decide on a bone scan. The bone scan is pretty inconclusive, blocking and imaging don’t give any definite answers but based on what we see in the ridden exam we decide to inject her neck. This seems to give some relief when we get back to tack/hand walking but she is still off the LF. Should also mention both fronts ultrasounded with no findings.

Then we get to May. Sport horse vet back to the barn and she’s actually looking ok. Not perfect. The more she works during the exam, the better she gets. Vet recommends putting her back into ‘get into shape work’. Some days are better than others, and then we have a brief time where things feel pretty darn good…THEN she starts to look off on the RF. UGH! Sporthorse vet out; she looks terrible. He recommends getting another horse. Well that’s not going to happen so decide to MRI the RF.

RF MRI is inconclusive. But she does have elevated insulin levels. When she is at the clinic she is managed as IR and loses quite a bit of weight—all for the good. All of this of course is a big UGH! The vet from the clinic where we had the bone scan and the RF MRI comes up for a ridden lameness exam. The high 4 block makes her completely sound. After this… ultrasounded all 4 legs, spine, SI, neck with nothing jumping out. What did jump out was her extreme sensitivity to palpations.

Decided to do a muscle biopsy for PSSM. Positive for PSSM2 and still waiting on the genetic PSSM1 test results. Without going into a ton of detail, this does explain so many things about her over the whole time I’ve had her. She is now currently on soaked hay, low NSC feed etc. I also added a tri amino but waiting on full management instructions.

In the meantime, I am tack walking and trotting her a tiny bit 6 days a week. She is still short/gimpy on that RF, especially tracking left, and that has everyone, including the very good and renowned lameness vet, completely stumped. It does get a bit better but is not perfect after some warmup and time, which tracks with the PSSM diagnosis. I know this all sounds nuts, and probably all over the place, and I’ve probably missed a few key details, but it has been a very thorough and systematic progression, so please feel free to ask further questions. Thoughts are welcome, and I know you’ll want video, but I am hesitant. Anyway, Thanks in advance!!

[seabreeze]

No thoughts, really. Just compassion. Really hope you can get her sound again so you can ride and further enjoy your mare. Best wishes!

[Dr_Doolittle]

I’m with @seabreeze - no advice, but my heart goes out to you. This is so frustrating!, and hope you will eventually get to the bottom of it.

Just a thought (a pretty common one on COTH), have you considered Dr. Green?

Hang in there.

[vxf111]

I’m as puzzled as you about the lameness but FYI that feeding regimen you started is more in line with PSSM1 than PSSM2 and at this juncture PSSM2 is what you know she has (and as a warmblood, PSSM1 is less likely though not impossible). So in terms of the PSSM2 that’s not really the way to manage the condition through feed.

[IPEsq]

How high up was the MRI imaging on the RF?

[Junebuggie]

Thank you! I apppreciate any good thoughts sent my way.

[Junebuggie]

Thank you! I have considered Dr. G. but not quite ready to throw in the towel yet. That scenario is also further complicated by my location (northern NE). There are not a lot of places around here for that, and I would want her to be close.

[Junebuggie]

Hi thanks for chiming in…I forgot to mention that on top of everything else, her insulin levels were through the roof when she was down for the RF MRI, so now we are managing her for that as well, hence the soaked hay etc. She has thankfully lost quite a bit of weight since starting that regimen, and I am hoping that can only help the whole of things.

[Junebuggie]

Hi - to her knee. I have wondered if there is something higher up, but vet doesn’t think so. Any thoughts welcome.

[vxf111]

Okay, understood. Boy just with what you’ve diagnosed you have so much going on and then the undiagnosed lameness on top of it. I don’t even know what to say?! Did you block bit by bit going up the leg to at least isolate specifically where the lameness is?

[Junebuggie]

Hi - Yes we started with the hoof and worked our way up…not sound until the high 4 block.

I will mention, for those of you playing along, something that also hangs in my mind. Last August I got on for a lesson and started to walk, and she was very clearly lame on the RF, jogged her on the lunge definitely very lame on that RF. Thought maybe absess. Have the farrier come out the next day. Right before he arrives, we put her on the lunge, and she is completely sound. Farrier ends up pulling the shoe just to see if anything is visible and hoof test her. Nothing at all, so we carry on with our business until fall when the wheels come off with the LF. I have wondered if there was something small that day that has turned into something big. I would assume a bone scan, MRI, US, X-ray, and blocking would have pointed to something if that were the case, but horses, so you never know.

We are going to try a different shoe week after next, no idea if it will help but at this point why not.

[vxf111]

Could it be pelvis? This is an unusual presentation for that. Have you tried injecting the stifles? Is she ever hitchy or locky? I’m stabbing in the dark.

[Junebuggie]

I guess it could be…at this point, I swear anything could be possible!! :// Bone scan did not light up that area and she hasn’t been sticky or locked up. We discussed hocks/stifles this last go round but decided to wait and try not to do too many things at once.

[vxf111]

It seems extremely unlikely to me but you ruled out everything I can think of that does seem likely

[4horses]

How’s her canter when she does canter?

I have a mare that is insulin resistant. Conformation wise she has crooked back legs that should cause all sorts of issues. When I brought her home I tried really hard not to fall in love with her. I didn’t want her. She’s the same age as my other horse and she would probably go lame because of her conformation… She was the most obese horse I had ever seen. But, I brought her home and immediately put her on a diet and in work. Once I had her for a few months, I realized she was never leaving me. She was just about perfect. This year she had abscesses in both front feet… but she never even went lame which was weird but the farrier confirmed she had it. Anyway I cut way back on her pasture and hay access and she seems fine.

Contrast her to my other mare. Conformation wise, she’s just about perfect, but she’s exercise intolerant. About 2 miles under saddle is the maximum she can do without having a muscle episode. As she’s aged, it’s gotten worse. If you worked her hard 7 days a week, as a younger horse, she would improve. Now she’s not sound and not rideable except for short hacks. As a young horse, she could do 15 miles, easily. I’ve started wondering about sarcocystis fayeri or whether this is age related degeneration. I suppose I’ll have to get a muscle biopsy to find out. She’s just not right. Her muscles are tight, she’s lost her topline despite all efforts to build topline muscles, she trips, and some days it seems like it’s hard for her to pick up her feet. I always thought she had pssm type 2, but I can’t help but wonder if there’s something else we are missing. Vitamin E and Selenium supplements did not help. She’s pssm 1 negative and negative for everything else on genetic testing. Maybe Cushing’s is aggravating whatever is wrong with her? I just don’t know. EPM can present as lameness, but does not really match… Pssm 2 should respond to exercise and diet and hers doesn’t. She’s not neurological…

Does pssm type 2 always progress? Perhaps this is sarcocystis and I need to treat with antiprotozoal drugs? I’m not certain a muscle biopsy will rule that out… maybe she has the horse form of muscular dystrophy and this is degenerative.

I’ve seen horses tie up with severe muscle fasicilations. She doesn’t do that.

If your horse has pssm type 2, I would want that horse on a 7 day exercise schedule, with 20 minutes or less of exercise at a time. After doing that for at least a month, then evaluate for lameness issues. Any time off, probably will aggravate the condition.

[Elouise]

So, I am going to throw out a few thoughts. Maybe? Maybe not? You probably have already addressed the below, but thought I’d ask anyway.

So, I knew a horse that had EPM and it showed up initially in/with issues the front legs; developed big splints, wouldn’t pick up one lead (down the road prior to diagnosis). That one was seen by multiple vets and had various tests. It wasn’t until it went a tad neurological that it was diagnosed and treated. Have you done an EPM test?

Also, with your horse’s high insulin levels; could she be having reoccurring bouts of slight laminitis that are so mild to not really be detected other than her feet are uncomfortable and the legs/ligaments/muscles are having a tough time dealing with her feet being sore.

And since I endured this…do you really think your farrier has your horse balanced and well shod?

Have you done a bute and robaxin test?

And I presume you have run a Lyme test?

Have you run a regular blood test? Blood levels?

Hopefully the collective minds of COTH can help you and your horse out.

[IPEsq]

Where did she palpate sore?

You’d think MRI to the knee would catch something that blocked out with a 4 point block.

[Junebuggie]

How’s her canter when she does canter?

Her canter is a highlight, and she’s a flying change machine. The couple of times we have cantered lately, she’s happy to do it but does feel choppy/short strided. definitely more so than she has in the past. We have not had any issues with the canter at all. Our PSSM symptoms have been lethargy, stiffness, looking terrible/lame all around starting out, cranky holding up her hind legs for the farrier, and sensitivity to palpation. Interestingly enough, she does get so much better once she warms up and has not shown any signs of exercise intolerance, tying up, or severe muscle tightness. She has, well, at least until the last few months out of full work, been well muscled with a beautiful topline.

I am just entering my crash course about PSSM 2/MIM but from what I understand, it does progress but can be managed. What I am coming to see is that there are so many variations and every horse is different and what works for each individual horse can take some hit or misses figuring it out. We are currently tack walking/tiny bit of trot 6 days a week.

Thank you for sharing your horses stories. I find these so helpful and interesing.

[Junebuggie]

Hi - yes many of these bases covered.

EPM - negative
Lyme - negative as of now but we have battled chronic infection in the past, and minocycline has been our go-to.

The recurring mild laminitis is certainly on the table, but it seems that if her feet were bothering her, blocking would make her sound. Rads taken of the hooves after the RF MRI showed nothing of interest. But maybe it could be so subtle. This is where I am wondering if a different shoeing set up will help. That will happen week after next. I am totally confident in my farrier.

We did a bute trial early last winter for the LF lameness with no change. Nothing since but have been thinking about a robaxin trial once we get the PSSM situation sorted out. Trying not to do som many things at once!

Oh, and yes, regular blood tests are OK.

Thank you for chiming in!

[Junebuggie]

Palpation especially sore over SI and lower lumbar. US in those areas looked fine.

You would think that about the MRI/blocks/ultrasound, this is what is so incredibly frustrating. It doesn’t make any sense, even vet says so.

I am very anxious to see if our shoeing changes next week make any difference.