PSSM/head tilting/hind end lameness- Help me solve this!

Hello,
I have a horse with lots of issues and need all the help I can get in figuring this out. I have worked with lots of vets and every time we solve one issue another comes up. I will try to sum things up for the sake of time. If you need more details on something mentioned just ask.

I have a 6 year old Belgian Warmblood mare (not draft cross) who was diagnosed in the fall of 2011 via muscle biopsy with type 1 mild PSSM/EPSM. She has been on a low starch and high fat diet since then. Muscle tone is now normal. She has always had stifle issues, but in the past 6-8 months the below issues developed.
Prior to this diagnosis she was tested for EPM with blood work and spinal tap but was negative. Her neuro exam was normal once she developed normal muscling via PSSM diet. Overall she is not the most balanced or coordinated horse- has always had issues with staying relaxed and balanced when cantered under saddle.

Current issues:
Head tilting and sometimes shaking worse when going to the left, not present at walk, bad at trot and worse at canter. Not seen while under saddle- only when lunging or free lunging without or without any tack on. Sometimes seen in turn out or similar stretching/tilting while in cross ties. Teeth are fine. I would see her head tilt like this as a baby once in a blue moon but now its every time we work. (see video) Hock lameness- tested positive in flexion tests for both hocks, right was worse. Had both injected 2 weeks ago. Improved in terms of more flexion and hind end power, but not sure if they worked entirely.
Stifles: Intermediate UFP, worse with right stifle. Had internal blister done 5 weeks ago, helped a lot but still have some issues. (has full turn out in dry lots) Had 2 blisters done as a 2 year old but the effect wore off. Now considering surgical method.
Occasional muscle soreness in hind end/glutes
Out of alignment- atlas and or sacrum have been an issue.

Other issues:
High head set at canter
Resistance to pick up canter, worse to the left
Swapping back leads
Dropping out of canter
Lack of power in canter
Bunny hops with both back legs sometimes when cantering fast
Canter never looks effortless for her, she prefers to trot
Kicking out when asked to pick up the canter on the lunge line
Sour mood- seems like she is always uncomfortable in some way, but is such a willing horse she will work under saddle well because she knows she is expected to behave.

Chiro helped at first and now doesn't. Head tilting developed when she came home from 4 hr. A week dressage training (was in training for 8 months). Symptoms list above became noticeable at a show 1 week prior to her leaving training. She is lunged way more at home due to my back issues- I can't ride as frequently. I'm sure this hasn't helped her joints but I have to keep her moving somehow because of the PSSM.

That is as brief as I can be. ANY advice is helpful. I have seen multiple threads online about horses that are almost identical to mine in terms of hock and stifle issues/lameness, PSSM or suspected PSSM, back/hind end soreness, sacrum alignment issues, etc. Somebody help me fix my horse- I can't stand to see her uncomfortable. I am now considering nerve blocks or investigating the head tilting as a separate issue than the hind end lameness (vestibular, balance/neuro issue, maybe do an MRI or scope her pouches?) We are also considering surgical splitting of stifle ligament (not cutting it entirely). Another note: she had xrays of her hocks and stifles 2 years ago and they were perfectly fine.

My my, that is one unlucky horse.....poor girl....poor owner also.

Okay, IF she was mine:
Head x-rays, searching for tooth infection or the like
Thoroughly examining her diet again. She might have to be maintained on 20-25% fat in her overall diet, since she is positive PSSM/EPSM
For UFP, i'd go non invasive, square, and I mean SQUARE toes behind.
In general, I would concentrate on the EPSM.
A different chiropractor/ bodyworker and look into acupuncture.

On ruralheritage.com is a lot of info about EPSM/PSSM, absolutely worth reading.
I feel for the both of you......

So far as her head, have you checked her ears? Made sure there were no mites or infection? My mare had similar head tossing, pushing head to the side, etc. and turned out there were these little flies laying eggs that were the culprit. Just lazing around, didn't seem to bug her, and her ears weren't sensitive to touch (unless you REALLY rubbed them at the base) but when working she would toss her head or try to hang it sideways, would get worse as her gaits progressed. (Though this was on the ground and under saddle)

The good news was a few hours of making my mare extremely upset and having homocidal thoughts against my existence, the problem was fixed.

Seems like with all the other things going on that it may not be something simple like that, but I hope you get to the bottom of it and she gets to feeling better :(

I am not familiar with these issues at all, so I won't try to give other suggestions, but it does look a lot like what my mare was doing.

Wow Harmony, I do feel for you....and your horse. I agree with Wausuaw to look into something facial with the ears. Maybe it's an inner ear thing? Maybe it's mites. Maybe some type of nerve thing, even though she doesn't seem to be leaning on the halter when lunging. I really wish I could tell you where to start with this one.

I don't think it is EPSM related, but you just never know. If you have read other threads on this site, I'm sure you've seen mine. I have one EPSM Type I pos horse and the other is Type I neg, but have not ruled out Type II. Mine are on the diets and have been for about a month.

I actually contacted Dr. Beth Valentine, DVM, PHD up at Oregon State University. I believe her email address is on the Rural Heritage website Deserthorsewoman mentioned. She will get back to you in a day or so via email. She is awesome.

I will watch this thread for sure. Kudos for you to be able to do so much for this horse. She is very lucky.

Deserthorsewoman: She is currently on Progressive ProAd Ultimate (vitamin/mineral) and Progressive Envision Classic (fat supplement). The fat supplement is 26% fat per pound (.52 of a pound of actual fat- so she gets a little over a whole pound a day and she is not overweight). She gets alfalfa pellets for taste, MSM and the joint supplement Actistatin. Her hay is professionally analyzed and well within ESPM requirements so I'm not sure what further investigation I can do in the diet area. She does tolerate grass, but has not been on it in months. The hind end muscle soreness on occasion makes me think EPSM though. I have heard a lot about Magrestore and Equiwinner (electrolyte) patches. Maybe I should look at those. She is on a sugar free electrolyte in the summer. I can try squaring the toes, but we have tried some farrier work and it didn't help. I am familiar with Dr. Valentine and have talked to her/read her website.

Wausuaw: I don't think it's bugs, but I will double check her ears when I see her next. She does get insect bites in her ears in the summer and can throw a fit in the pasture but it has never looked like what she is doing now.

Oldhorselady: I have seen your posts. I don't think the head tilting is related to EPSM, I think it is her way of showing discomfort that is hind end related or specifically her stifles. The tilting has improved with the stifle blister and hock injections but it didn't solve it. I am considering investigating an inner ear thing.

Thanks for the support everyone. I will keep posting- I am waiting on a phone call from one vet and the other is coming out next week. I hope we figure this out, but I'm sure it will involve more months of frustration and thousands of dollars that we don't have, but will spend anyway

Harmony, we were just going through the fat problem of the diet with Oldhorselady's horses. You want 20-25% fat of the total ration. Grass hay has 2-3%, so you can do the math and see it takes more than just a lb of your high fat supplement.
I would first take care of the one subject you can without spending another fortune. The UFP could be an EPSM symptom, that's why I'd be for non invasive measures for that. What the square toe does: it's breaking over earlier, means leave the ground, before the leg comes to a complete stretch and the ligament can get caught over the patella. If it doesn't help, at least it hasn't done anything wrong.

I do agree the head tilting is something different.

Deserthorsewoman,

I will pull out the hay analysis and review her feed again. As far as her feet we did try the squaring of the toes exactly how you described and added shoes with extensions on the back for more support. I felt she did not improve, but I can always as my farrier if we could (keeping the shoes off) square her toes more than they are at the moment. We thought for a a year that the UPF was EPSM related but she has normal muscle tone and still had issues 6 months post diet change and while she was in regular dressage training. I suppose it could be, but there is no way I can work her daily or as extensively as needed to prevent UPF due to my back injury. All non invasive methods seem to require a whole lot of strengthening and maintenance. If 8 months with a trainer didn't help then I don't know what will. I have debated selling her for this reason because I can't ride without back pain so I may not be the best owner for her considering I can only tolerate a limited amount of riding. Clearly she is a mess and can't be sold right now. Such a sticky situation.

Are you doing any IV/IM joint supplements in addition to your IA injections (Hock injections)? I agree with squaring the toes too.

With the head shaking and tilting... the only additional things I can think of is to try some of the "head shaking syndrome" remedies. Fly mask that covers the ears, eyes and nose that is UV rated. You can also opt out of a few vaccinations to see if the situation improves (several people blame vaccines such as Rhino). Could it make a difference? Possibly.

Keep in mind there are legitimate medical reasons why a horse exhibits certain behaviors that become learned behaviors and training problems after their medical issues have been addressed. I would find a good driving trainer to build muscle back and teach your horse how to use himself again.

I have mostly dealt with small animals, but I would probably lean towards calling your mare's behavior some kind of vestibular or neurological head-tilting rather than irritation (after watching the video). Does she head-tilt if you trot or canter her in a straight line? I feel like she tilts to compensate for knowing she's unbalanced, but not quite how. If you rule out mouth issues, I might wonder about some kind of vestibular infection/disease.

Another possibility... have you checked her eyes/sight?

I am so sorry that you and your sweet mare are going through this hard time.

Just wanted to add... after re-reading your mention of her doing this as a foal, and also reading through your problems list, I really think you should have a vet do some kind of evaluation of her balance/vestibular function. (Just hypothesizing here!) I wonder if she had a minor vestibular infection as a foal that caused some kind of damage, which was emphasized or worsened when she was asked to do balanced work (ie. Dressage training).

Again, just throwing ideas out there. I wish you and your mare the best.