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.
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.
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.