Does this sound like PSSM?

[SoundTheBugle]

I have a 6 year old cob x clydesdale who has some issues, does this sound PSSM-y to those who are experienced with it?

• Severe arthritis in one hock diagnosed as a 5 year old despite being very low mileage - I've known him since 18 months so can vouch for his history. This was only discovered after a period of box rest for a cut. He was in full work (6 days a week, but only 1-2 short sessions in the school) and completely sound before this.
• Has always struggled to come back into work after time off - sticky and unwilling, could look unlevel until warmed up. Vets blamed this on locking stifle as he had a string of massive growth spurts and told me to work him through it.
• Cold backed - vets and physio again blamed this on locking stifle and told me to work through it as he was sound otherwise.
• Happiest when using an infrared saddle pad and needs rugging up despite being super fluffy
• Needed long warm ups and cool downs to produce decent schooling, but talented and willing when he was happy

He had surgery to fuse the hock in summer 2021, and has been out of work since. He was incredibly unhappy through the box rest and rehab process, and wasn't making the progress the vets expected. There was a question mark over ligament involvement but the vets suggested that they wouldn't be able to do a lameness work up before he was more comfortable in his hock so he was turned away with a "wait and see" attitude and moved to a yard with better facilities and turnout (though still not ideal). He was stiff through the winter and managed with devils claw, boswellia and bute as needed but has been sound and supplement free all summer when he's been out 7am-8pm. With the weather turning and winter turnout restrictions (out every other day, must be in by 6) he's stiff and uncomfortable again. He's been rugged up despite being super fluffy and a bit chubby (not too bad though!) and is much happier for it. He's also starting back on devils claw to see if that makes a difference too. Sadly there aren't any better options for turnout for him (I've looked!) so he gets hand walked for half an hour to an hour on bridleways on the days he's in and is turned out for an hour or so in a paddock on those days too.

Given his history of coming into work uncomfortably, no matter the time of year, and how much of a difference rugging up has made - am I looking at PSSM being likely? He thrived on a 6 day work week and had a complete personality change when he was first being rehabbed and the previous yard was only allowing turnout for a couple of hours a day. I might be clutching at straws, but I'm almost hoping that there's something else going on that can be managed because if it's just the arthritis and he's uncomfortable half the year despite the fusion then it doesn't seem fair to keep him going when he's so young and has another 10-20 years left.

 

[SpotsandBays]

The PSSM1 hair test is only £30 through animal genetics uk. It’s cheap and simple to do so definitely worth it for peace of mind. PSSM2 and the variants surrounding that are difficult to diagnose - there is a hair sample test but this isn’t peer reviewed and most vets don’t recognise this - it’s also quite expensive. Other ways to test are via muscle biopsy but others with more knowledge than me will be able to advise more on that.
I’d start with the type 1 test for sure, some of your horses symptoms fit, but each horse is different and the issues you’re facing may be related to something else (like the hock issues).
Join the pssm Facebook groups (pssm and mfm awareness - is one of them) there is lots of information on there too, good luck!

 

[Fransurrey]

Possibly, but your vet might be right, too. I'd agree with Rosietaz and get the PSSM1 test done. My boy had a lot more symptoms (but it may be you just haven't mentioned them or linked them to PSSM), but if your horse is heterozygous, the symptoms will vary more according to management and exercise routine. My physio said it was unlikely in mine as he has never had the muscle twitching or classic tying up, but he is confirmed heterozygous PSSM1.

 

[dorsetladette]

I'd say some of the issues you have experienced sound PSSMy but they also sound like my old boy. We treated hocks for arthritis last year but it turned out to be further up the leg, stifles. I'm not a fan of messing with stifles as they are a complicated joint (IMHO) so we buted and retired. He was generally over weight as out 24/7 and retired or out of work for a long while, I tried to reduce his weight by under rugging or not rugging but this would make him stiffer and visibly more uncomfortable. He was always happier rugged (keeping the stifles/hips warm). His diet was carefully managed as he had a history of ulcers, we treated him as if he had PSSM and he also had (old man) balancers aimed at joint support.

 

[Pippity]

I'd say do the PSSM1 test and take it from there. Alternatively, shovel him full of vitamin E and see if it has an effect. (My p1 15hh cob is on 8000 iu per day, as a guide.) I saw an effect in a couple of days with mine, with her tail relaxing and being able to bend, rather than being a broomstick. After a month or so, her bum was lovely and round where it used to fall away from her spine.

If you don't want to risk shovelling vit E down a horse that doesn't need it, you could get your vet to pull bloods and test the E levels. (I get this done every six months or so, just to keep an eye on how she is.)

 

[SoundTheBugle]

The PSSM1 hair test is only £30 through animal genetics uk. It’s cheap and simple to do so definitely worth it for peace of mind. PSSM2 and the variants surrounding that are difficult to diagnose - there is a hair sample test but this isn’t peer reviewed and most vets don’t recognise this - it’s also quite expensive. Other ways to test are via muscle biopsy but others with more knowledge than me will be able to advise more on that.
I’d start with the type 1 test for sure, some of your horses symptoms fit, but each horse is different and the issues you’re facing may be related to something else (like the hock issues).
Join the pssm Facebook groups (pssm and mfm awareness - is one of them) there is lots of information on there too, good luck!

Thank you, good to know that the hair test is a cheap option. Might get him tested for Christmas as I've been meaning to get him colour tested too, so 2 birds one stone and all.

 

[SoundTheBugle]

I'd say some of the issues you have experienced sound PSSMy but they also sound like my old boy. We treated hocks for arthritis last year but it turned out to be further up the leg, stifles. I'm not a fan of messing with stifles as they are a complicated joint (IMHO) so we buted and retired. He was generally over weight as out 24/7 and retired or out of work for a long while, I tried to reduce his weight by under rugging or not rugging but this would make him stiffer and visibly more uncomfortable. He was always happier rugged (keeping the stifles/hips warm). His diet was carefully managed as he had a history of ulcers, we treated him as if he had PSSM and he also had (old man) balancers aimed at joint support.

We're also dancing the line between keeping weight off for his joints and keeping ulcers at bay as he developed them when he was in and out of horsepital. When we made the call to go ahead for surgery my vets and I decided that if he having him on bute to be comfortable wasn't a fair long term solution for an otherwise healthy young horse so I'm hoping there's something else going on that we can manage.

 

[SoundTheBugle]

I'd say do the PSSM1 test and take it from there. Alternatively, shovel him full of vitamin E and see if it has an effect. (My p1 15hh cob is on 8000 iu per day, as a guide.) I saw an effect in a couple of days with mine, with her tail relaxing and being able to bend, rather than being a broomstick. After a month or so, her bum was lovely and round where it used to fall away from her spine.

If you don't want to risk shovelling vit E down a horse that doesn't need it, you could get your vet to pull bloods and test the E levels. (I get this done every six months or so, just to keep an eye on how she is.)

That's really helpful, thank you. What were your girl's symptoms if you don't mind?

 

[SoundTheBugle]

Possibly, but your vet might be right, too. I'd agree with Rosietaz and get the PSSM1 test done. My boy had a lot more symptoms (but it may be you just haven't mentioned them or linked them to PSSM), but if your horse is heterozygous, the symptoms will vary more according to management and exercise routine. My physio said it was unlikely in mine as he has never had the muscle twitching or classic tying up, but he is confirmed heterozygous PSSM1.

What symptoms should I be looking for? I've not known him to muscle twitch or tie up, but he always had fairly solid muscle.

 

[Dexter]

 

[SoundTheBugle]

That's really helpful, thank you. The canter is interesting as he's always struggled to pick up the canter and his canter is definitely his weakest pace - he's big striding for a small horse but his canter is very small and tight

 

[ycbm]

Has his back been x rayed? It could be PSSM but it's also symptomatic of kissing spines.

 

[Pippity]

That's really helpful, thank you. What were your girl's symptoms if you don't mind?

The biggest one was when she tied up! Before that, she'd been a bit stuffy and backwards at times and generally stiff, but nothing that seemed more than, "Oh, that's what cobs and mares are like." It was only when she tied up, got diagnosed and I started treatment that a lot of niggly things started to resolve.

I'd always struggled to build muscle on her bum, but that pretty much grew itself as soon as she was on the vitamin E. Her canter had been pretty much non-existent. She still struggles with the transitions, but once she's going, she's got a lovely canter now. She'd always been happier in summer than winter, but I put that down to arthritis. Once I started rugging her more heavily and wearing an exercise sheet, she became much happier. (I'd always been of the "let her shiver some weight off," camp.) She also had that camped out stance but, again, that was put down to arthritis. She still tends to stand with one leg stretched right out behind but, as she alternates them, I suspect it's just habit.

She's always been, um, 'athletic' in the field, so adding daily exercise didn't make much difference, and was just getting me stressed and ensuring riding became a chore rather than fun. She's back down to 3-4 ridden sessions a week now. However, I do make sure that I get a decent amount of trot and canter in every session. Walk isn't enough. I also have to be extremely careful that she's fit enough for everything I ask her to do. Building up fitness is done very slowly.

 

[SEL]

I'd do the PSSM 1 test in your position.

I've had two with it now and they presented very differently. My mare is a part bred draft and sounds much like your boy in that she had problems with her hocks diagnosed when she was just 6 and barely done anything. I suspect muscle tightness meant she never held herself properly so the hocks took the strain. She needs to be literally steaming under her rug at this time of year for those hindquarter muscles to remain soft and she's on 24:7 turnout since a suspensory injury brought her riding career to a halt.

My maintenance dose of natural vitamin E is about 4000iU but you can go a lot higher for the short term and without access to grass I'd feed it to yours irrespective of PSSM status.

I know you already know it but the restricted turnout won't be helping the arthritis or the muscles.

For symptoms mine gets tight over her hindquarters, grumpy (yawns a lot) and you touch her girth area at your peril. We did treat for ulcers before the PSSM was identified but the specialist who did the scope was perplexed because her management was very gut friendly and he thought I'd find another issue in time. We get odd hoof flare too because of shifting lameness as she tries to compensate for her sore muscles. ETA - on a bad day it felt like you were riding with the handbrake on, but she'd often buck like a rodeo display if you asked for canter

My now sadly deceased gelding was a lot more robust with his PSSM and it only really showed up in Spring if he had too much grass. He'd get a very sticky right stifle which was my wake-up call that the grass was growing and he needed to be off it.

 

[SoundTheBugle]

Has his back been x rayed? It could be PSSM but it's also symptomatic of kissing spines.

No it's not, but none of the vets or physio have ever suggested it to be honest. Thank you

 

[SoundTheBugle]

I'd do the PSSM 1 test in your position.

I've had two with it now and they presented very differently. My mare is a part bred draft and sounds much like your boy in that she had problems with her hocks diagnosed when she was just 6 and barely done anything. I suspect muscle tightness meant she never held herself properly so the hocks took the strain. She needs to be literally steaming under her rug at this time of year for those hindquarter muscles to remain soft and she's on 24:7 turnout since a suspensory injury brought her riding career to a halt.

My maintenance dose of natural vitamin E is about 4000iU but you can go a lot higher for the short term and without access to grass I'd feed it to yours irrespective of PSSM status.

I know you already know it but the restricted turnout won't be helping the arthritis or the muscles.

For symptoms mine gets tight over her hindquarters, grumpy (yawns a lot) and you touch her girth area at your peril. We did treat for ulcers before the PSSM was identified but the specialist who did the scope was perplexed because her management was very gut friendly and he thought I'd find another issue in time. We get odd hoof flare too because of shifting lameness as she tries to compensate for her sore muscles. ETA - on a bad day it felt like you were riding with the handbrake on, but she'd often buck like a rodeo display if you asked for canter

My now sadly deceased gelding was a lot more robust with his PSSM and it only really showed up in Spring if he had too much grass. He'd get a very sticky right stifle which was my wake-up call that the grass was growing and he needed to be off it.

The description of your mare sounds very similar to my boy, thank you. Definitely worth testing I think.