Becky and Krissy, can I applaud you both right now??
You are each handling this issue extremely competently and I feel your horses are very, very lucky to have you. You can look up my topics from spring of '08 to find out what happened with my own horse, but suffice it to say my gelding locked terribly for years and I tried everything I could think of to no avail. He was literally fit enough to run marathons (we compete in Combined Driving against the big horses), on a wonderful joint supplement, getting plenty of selenium and not overloaded on protein, etc. etc. and nothing helped. I even installed a board across the door of his stall so he had to step over a cavaletti every time he went out for water or in for food or potty! I figured that might help the same way having stairs in your house gets you toughened more than once a day on a StairMaster will.
We did cavaletti work too, and as much hill work as I could find in our road-riddled area. Nothing helped.
We finally took the surgical route when he was 7 (doing the splitting in fall) and then when that made him WORSE we did the full desmotomy in spring just before his 8th birthday. I was so worried about it, but it's been wonderful! He hasn't locked once since the day of the surgery and has not only gained 10lbs of muscle in his hindquarters but has completely changed how he moves. He's so much happier now.
While doing farm visits in my area recently I've been introduced to several young minis who lock, and it's been interesting. One of them is a lot like Kody and there's no way, in my opinion, that she is going to get better without surgery. Yes she's young and skinny and undermuscled, but she recoils back and out to the side with every single step she takes at a walk. I don't think she's capable of doing enough rehab to even attempt to remuscle her! Like Kody, she's so locked in her pattern of moving that she probably can't break it on her own. This mare is three and has been doing this since she was a weanling. Her full sister does it too, by the way, although neither parent does and neither do any of the other foals raised identically. Hmm. Genetic component, anyone?
They're turned out in a large pasture to run and play in a herd all day and seem to get plenty of exercise. Anyway, at that point I was even more convinced that when a mini does this that badly it isn't going to go away no matter what and they will probably need surgery eventually. The sooner the better in a terrible case like that, so they stop doing so much damage to their joints and muscles in the back and don't get locked into that pattern of movement!
Kody had eight years of moving that way to learn to undo and it took him almost a year and a half of steady dressage work and physical therapy to learn to move naturally. I still get teary when I see him kick at a fly on his belly without thinking- that's such a huge thing for him.
But the other two horses I've seen do this recently were a little different. Yearlings, both of them, skinny and gawky and at a big growth stage and in fairly small paddocks that didn't encourage running around. And in each case, when they locked the leg actually locked in full extension and could not be released at all without outside assistance. This is not the pop-and-release locking I was familiar with, and that both my horse and the three year old I saw did routinely. The one horse required a vet's assistance and some muscle relaxants to release the leg the couple times he locked but was normal in between events and is now doing fine as a two year old in a home where he gets plenty of exercise. The other colt I can verify personally was fine for the first year and some-odd of his life and then locked hard in the right hind a couple of weeks ago and couldn't release it for two or three minutes. When he did it tried to lock hard again with each step so we kept him moving for a few minutes until it loosened up and then kept him turned out with a buddy in a large space for the next couple of hours and gave him some Banamine. He didn't lock hard like that again but is "poppy" feeling in his hindquarters if you lay a hand on him while he's moving and seems to be striding a bit short back there at a walk and trot. This colt is one I'd wait on trying surgery for as there are so many factors that can be remedied which may improve or completely fix this tendency. He's going to be turned out with a more active horse who will actively encourage him to run, he's getting lots of groceries at the moment to get some weight and muscle on him and he's been placed in a larger turnout area overnight to help him think a little freer mentally. (My gelding would consistently lock up the moment he walked through a stall door even though he could do the exact same maneuvers just outside the stall with ease. You could see the look of dread on his face as he anticipated of a night of locking and he'd tense up so much he started doing it!) We'll see how that goes but I'll bet that as his front end catches up with the growth of his hindquarters (he's butt-high right now) and he muscles up he'll probably stop doing it. If not, we'll consider surgical options.
I guess my point is that there really do seem to be several different
kinds or at least degrees of upward fixation of the patella and those factors are all going to play into whether or not your guy will get better without surgical assistance. The yearling I think may improve only started doing this after a major growth spurt that straightened out the angles in his hind limbs, is skinny, and did it during the period of confinement itself. It sounds like your guy did not lock DURING his time of poor nutrition, confinement, and bad feet but started this recently and that concerns me a little. So does the heat and the look of pain- have you checked with your vet to make sure he doesn't have an actual injury? There are many kinds of stifle problems, upward fixation is only one! Stringhalt and several other things can look similar on first glance.
If you get a confirmed diagnosis of UFP, then the exercise program you've described should improve things for him at least a little. If nothing else he'll be happier!
I can't tell you how long in months or days, but I'd say if he's gained strength and muscle tone all over and has become fit and tough and he's still doing it you've got a problem. The kind that's going to go away should do so as soon as the problems that caused it (undermuscling, selenium deficiency, etc.) are remedied.
One thing you might look into that I didn't consider as a therapy when my horse was locking is massage. I've found a wonderful practicianer that does myofascial release, sports massage, energy work and red-light lasers/pulse magnetic therapies and is working with my gelding on his current back injury and all the deep muscular problems left over from having locked every single day for eight years.
She's awesome! She is able to tell me all the areas he's got movement blockages and is helping to reintegrate his body and release all that deep tension so he can move more soundly. If he'd had someone like her when he was locking he might not have gotten so bad in the first place and would be in far less pain now.
Massage is not going to cure the locking, but it sure could help relieve overall soreness and muscle knots that develop as a result of the physical stress of locking.
Kody saw a talented and gentle chiropractor for years and she helped a lot, but now I'm gaining a deeper osteopathic understanding of how much of the constant reoccuring misalignment in his back was caused by muscular imbalance. Fix the muscles and he doesn't NEED a chiropractor anymore! The surgery by itself allowed him to track straight and changed the uneven wear patterns on his hind hooves, the chiro kept temporarily straightening his back and relieving his discomfort, and now the massage practicianer is releasing the muscles that kept pulling it back into misalignment and providing a much deeper level of comfort for him. Kody also has a Reiki practicianer now and he LOVES that, but I don't think it would do anything to address the stifle issue except to relieve pain.
Keep on with your program as is Becky, and let us know how he does. Your little guy can go on to lead a useful, wonderful life!
Leia
