I gave her a couple months off and she seemed fine, so we started riding her again this spring with no problems. Well, a couple weeks ago my Dressage coach got on her for me to give me her opinion and then took her over some jumps. Next ride, problem was back - she was weirdly swinging her right hind leg and almost stomping it down as she stepped.
Got the vet out today and his diagnosis is "functional string halt". Has anybody dealt with this before? Had it been more blatant, I probably would have picked up on it sooner but it's so minor and doesn't affect her movement at all (she still walks, trots and canters happily with no qualms), so we just assumed she had a muscle out in her back or her hips.
He did several flexion tests and trot outs, and there's definitely no soreness for her. It's literally just a "gait deformity" right now. His advice was to make her lose weight (she's probably 50-75 pounds over weight right now from all the time off), and get her back in shape. He advised to lay off the jumping and training, and that actually endurance training would be perfect for her (trotting straight lines). He also mentioned that sometimes diet plays a role and it has been related to PSSM, but Zierra gets literally no grain and only eats hay and grass.
Any opinions or experiences to help me out with? String halt seems to be a very mysterious condition in general, and I am thanking the mother of all that is green it's not more serious. I mean, honestly, who can be disappointed with "RIDE YOUR HORSE MORE!"????