Anatomy experts - what muscle is this? Muscle knot, causes, fixes?

[fivestrideline]

One of my horses has a knot of tightness in his “hamstring” at the bottom on both sides, pictured below (though not as obvious as it is IRL):

Can anyone tell me what muscle this actually is? All my googling is just bringing up vague illustrations that don’t seem to line up with the bump/knot I am seeing. The tightness and soreness of this horse’s hind end has improved greatly in the last few months, but this has been lingering/become more apparent.

Any ideas as to what could cause such a lump of tightness, and how I might help it? It is equal on both sides.

Am I just worrying about normal anatomical features?

[TWH_Girl]

That area circled makes me think equine fibrotic myopathy. What are his issues otherwise? Not sure that would fit depending on what’s going on and how he presents.

[PaddockWood]

This is from my Jack Meagher book “Beating Muscle Injuries” and I highly highly recommend getting a copy. You can find them used online. I’m no pro but it seems this is it?

[fivestrideline]

@TWH_Girl

What are his issues otherwise?

Typical green OTTB straight off the track . He hasn’t been put into major work due to weather and my own schedule, but his hind end is tight, he’s got NPA behind (his feet were frightful when he got here), and he has historically struggled with catching stifles. All mild enough to simply be growing + trackiness + lack of muscle. All of the above have improved with work and attention.

@PaddockWood

I’m no pro but it seems this is it?

Gastrocnemius? I think that lines up. Otherwise it’s the muscle just above (or just the bottom part of the muscle just above).

I have used the Posture Prep on it and it really makes zero difference, but pressing into the area with the flat of my hand for a minute seems to help. It also seems to improve post-ride vs before getting on. Off to google!

Also if I can find that book for a reasonable price I’ll grab it! I have some empty space on a bookshelf anyway.

[IPEsq]

Well that is roughly the “back of the knee” area, meaning that it’s near the ends of the (in human terms) hamstrings and calf muscle groups. Including the tendons. And there are some thick bands of fascia in that area. I am not seeing anything alarmingly abnormal in your photo…perhaps you have some overdevelopment of the caudal biceps femoris or the semitendinosis?

In that region you have an acupuncture point that can be suggestive of hock pain. There are lots of reasons for overactive hamstrings though. Not uncommon to see that in a youngster where young horse isn’t super effective at using his glutes.

[fivestrideline]

@IPEsq

Well that is roughly the “back of the knee” area, meaning that it’s near the ends of the (in human terms) hamstrings and calf muscle groups. Including the tendons. And there are some thick bands of fascia in that area. I am not seeing anything alarmingly abnormal in your photo…perhaps you have some overdevelopment of the caudal biceps femoris or the semitendinosis?

In that region you have an acupuncture point that can be suggestive of hock pain. There are lots of reasons for overactive hamstrings though. Not uncommon to see that in a youngster where young horse isn’t super effective at using his glutes.

Thank you!! This is exactly what I needed to hear.

He’s definitely not effectively using his hind end (yet), but it’s a work in progress. I think he just went from “everything is tight as a bowstring” to “this spot is still tight but the rest less so” and it made these knots more obvious. I’ll jot down your observations just for my future reference since it makes a lot of sense.

I am prepping to add pole work and other booty-building work to his routine now that we have Steering and Brakes mostly in place (and a saddle that seems to fit). Hopefully that will sort out the rest of him in the process

[TWH_Girl]

Glad it doesn’t seem like a serious issue. My guy has tight hamstrings too. He’s due for massage and is not a fan of posture prep AT ALL.

[fivestrideline]

This one doesn’t mind the PP, it just didn’t seem to have the same effect on those knots vs the rest of him.

Mr NQR that I have HATES IT.

[NaturallyHappy]

I think @PaddockWood nailed it! I was going to post the exact same thing. I have that book, too.

[Arlomine]

Came here to say this. OP needs to really watch it. I’ve known several horses with this problem, and it can be career ending. I currently have one in my barn who came with it and she is remarkably good, almost normal range of motion and no weird flight pattern.

I would get a really good sport ver on this. Accupuncture, damp hot/cold, etc.

Lazer would probably really help it tons.

I would suggest being very careful trying to apply a whole bunch of stretching and “work“ to it. Yes, I think all that could help. But if you overdo it you can cause more tension and you don’t want it to develop into that fiberous tissue. Hence why I would get a sports vet on it.