Drinking/peeing seems back to normal now. We’ll have to keep monitoring blood for a little while.
He’s been in the stall with some hand walking per the vets. When I put him back in the stall today, he got a little wild and locked up the stifle trying to whirl around to the left. This time it looked like pretty normal UFP in the stance. It was quite stuck and he stopped after it locked. He then forcibly flexed the whole limb up high and then was fine.
I dunno…maybe going from the fittest he’s been in his life to halting work due to kidneys plus being locked in the stall due to mud triggered this. He has had some signs of stifle issues in the past in transitions but ultimately we concluded he was just locking up his whole hind end to protect his back. His back has been doing really well lately, and while it’s been harder to strengthen the left hind, he is still overall quite strong and hasn’t had any of those moments in a long time. And it never has locked while moving forward.
We nevertheless had worked up the entire left hind a few months ago to try to determine why his fitness was not building equally, and that included blocking the fetlock and stifle. There was 0 change in his way of going at that time, so we just upped the core strength part of his routine and now injected the hocks because he does have some bilateral arthritis and we wanted him to have some support while being asked to collect a little bit more.
I had one horse who minorly strained a stifle slipping while getting up in his stall. Perhaps that was part of this on Wednesday night? He does tend to lay down near where he pees, and with the excessive peeing, I could see things getting slick even with a good amount of bedding.
We are going to do an ultrasound tomorrow and start a series of IRAP on the stifle as an NSAID-free way to try to battle any inflammation. I know for UFP he will need more movement, but no one wants him turned out with the lameness this severe with the locking.
Any other reason for sudden severe upward fixation of the patella unilaterally? I’ve read about it secondary to luxation of the patella, but that would certainly show up on xray.