12/19/2022
*** WINDGALLS, and WHEN YOU NEED TO WORRY ***
I’ve seen a fair amount of scary advice being handed out on social media recently, about tendon sheath effusions, so I have decided to write a little article all about “windgalls”, which is the basic term for a tendon sheath effusion.
I would like to start by saying that a windgall is ALWAYS something to show some concern about. If it’s in just ONE leg, it is something to be VERY concerned about, as it indicates damage to the tendon sheath, or the structures within the tendon sheath.
If a windgall is present in both hindlimbs, both forelimbs, or all four limbs, then it’s more likely to be of idiopathic origin, and less likely to cause any future lameness concerns. But it’s still essential to note it, and essential to know what is “normal” for your horse; for example, if he always has mild tendon sheath effusion in both hindlegs (windgalls), but one suddenly becomes much larger than the other, this would be concerning. Windgalls are far more common in the hindlimbs, compared to the forelimbs, and if I find them in the forelimbs when the horse hasn’t just done a lot of work, such as a big event, I would be concerned about poor conformation or foot balance in that horse. If I find them in the hindlimbs, the horse is sound, and the swelling is soft to palpate, then I wouldn’t be overly concerned.
Windgalls can be “articular” - associated with the fetlock joint - or “tendinous” - an excessive amount of fluid in the tendon sheath. Both types indicate changes/inflammation within the structure. So although many horses have tendinous windgalls, especially in the hind limbs, they are never “nothing”. Some inflammation has caused that excessive synovial fluid to form, and a “swollen” tendon sheath is sometimes just as important as a “swollen” joint, especially if it’s in just one leg.
The tendon sheath “houses” several important structures, the most important of which is the deep digital flexor tendon (DDFT). Injuries to the DDFT are never good, as this tendon is very important, and very hard to fix. More on this in part two.
In the absence of any effusion (swelling), so in an uninjured, uninflamed tendon sheath, it is almost impossible to see or feel at least the upper part of it. You can only ever feel where a tendon sheath sits, when it has an excessive amount of synovial fluid in it, which is when it is inflamed. A tendinous windgall is therefore an inflamed or injured tendon sheath.
Part two of this mini series, will include the structures in the tendon sheath, and how we go about diagnosing which structure is damaged. I will also explain why I use contrast radiography, rather than ultrasonography, to diagnose which structure is damaged in the case of a single limb tendon sheath effusion, and why ultrasonography (US) of a tendon sheath can be very inaccurate. (Note I am talking about the tendon SHEATH and not tendons outside of the sheath, for which US is the gold standard).
Please share, as I don’t want to see another post with someone being advised that a single limb tendon sheath effusion, is nothing to worry about! The photo also shows you exactly where the tendon sheath is on the leg.