Tendon inflammation in horses: symptoms, immediate help & feeding

A tendon inflammation rarely announces itself with a bang. Much more often, it is a quiet suspicion: the leg feels a little warmer in the morning, the trot seems a touch uneven, and you wonder if you are just imagining it. Exactly at this moment, you want to know where you stand. This article helps you recognise the inflammation early, take the right first steps, and understand how you can support the healing from the inside.

We – Katja and Andrés – are writing this from over 20 years of experience at the yard, not from a desk. And right away, to be perfectly clear: this text does not replace a vet. An inflamed tendon needs to be palpated and usually scanned with an ultrasound. What we can give you is guidance for the weeks before and after.

What happens in the leg during a tendon inflammation

Tendons are the cables that transfer muscle power to the bones – above all, the superficial and deep digital flexor tendons at the back of the cannon bone. They consist of densely bundled collagen fibres and cushion a multiple of the body weight with every step.

In the case of tendon inflammation (tendonitis), this tissue reacts to an overload: the smallest fibre tears, invading inflammatory cells, swelling, heat, and pain. If the gliding sheath around the tendon is also affected, it is called tenosynovitis – then you often feel a soft, taut but elastic swelling along the tendon. Important to know: an inflammation is not yet a complete tendon injury. Rather, it is the warning signal before one occurs. We have described in detail how an inflammation turns into a true fibre lesion and how its rehab works in the article on tendon damage in horses.

The catch with tendon tissue: it is "bradytrophic", meaning it has a poor blood supply and low metabolic rate. An inflammation therefore does not subside overnight, and the repair takes weeks to months – not days.

The symptoms: what you need to look out for

The earlier you notice a tendon inflammation, the better the prognosis. The typical signs are:

• Heat: The affected leg feels significantly warmer than the other. Always compare both sides, ideally in the morning before any movement.
• Swelling: A thickening at the back of the tendon; in an acute case, the classic "bowed tendon" contour.
• Tenderness: Your horse pulls its leg away when you palpate the tendon.
• Unevenness to lameness: From "not quite right" to distinct lameness – depending on the severity.

A common fallacy: if the lameness disappears after a few days, the matter is resolved. False. Heat and thickening can remain while the horse is already walking "normally" again. It is precisely these silent inflammations that are the precursor to a major injury. If you feel heat or swelling, the horse belongs on box rest and you need to be on the phone with the vet – not back in training.

The first 72 hours: what counts now

In an acute case, early action is decisive. The following has proven effective:

• Cooling: Several times a day for 15–20 minutes with ice water or cooling boots. Cold slows down the inflammation and the swelling.
• Rest: Box rest instead of movement. Every unnecessary step on an acutely inflamed tendon can increase the damage.
• Involving the vet: They will decide on anti-inflammatory medication (NSAIDs), the ultrasound, and the further plan.

What you should not do now: "lightly exercise" the horse to see if it gets better. That is understandable, but counterproductive in the acute phase.

How you can support the healing from the inside

As soon as the acute phase has been treated by a vet, the question of building materials arises. Because the body can only repair a tendon as effectively as the necessary building blocks are available. Four nutrients are central here, and they work together:

• Collagen is the structural protein that the tendon fibres themselves are made of – the direct building material for new tissue.
• MSM (organic sulphur) provides the sulphur that stably cross-links the collagen fibres with each other, and has an inflammation-modulating effect.
• Glucosamine is a building block of the surrounding matrix and the joint structures.
• Hyaluronic acid keeps the tissue supple and is the main component of the joint fluid.

Research suggests that it is less about one megadose than about the meaningful interplay of these substances – they take on different tasks in the same repair process. We take a closer look at the studies behind this and how the bioavailability of oral hyaluronic acid should be assessed in our overview of joint supplements for horses.

Two things are crucial in practice. Firstly, patience: due to the slow tendon metabolism, consistent feeding for at least 8–12 weeks is the minimum. Initial changes often only appear after 4–6 weeks. Secondly, transparency: ask for the milligrams per daily ration. The EU feed regulation allows manufacturers to only provide rough compositions instead of exact amounts – but you have a right to know how much active ingredient actually ends up in the bowl.

The real problem: getting it into the horse

This is where most things fail in practice. You buy a good powder, mix it into the feed – and your horse sorts it out. MSM in particular has a strong taste, and horses are masters at selecting. In the end, the expensive active ingredient sticks to the bottom of the manger, and you never know how much has really been consumed. During rehab, this is further exacerbated: a horse that is already eating more fussily on box rest is even more likely to refuse the powder.

This is exactly where nuvallo move comes in. We have packed the four active ingredients into nuvallo move Snacks that you feed straight from your hand – no weighing, no dust, no sorting out. A daily ration of 6 nuvallo move Snacks (approx. 30 g) for a 500 kg horse transparently provides 1,500 mg glucosamine, 2,550 mg collagen, 2,250 mg MSM, and 150 mg hyaluronic acid. For an acute problem, you double the amount for 2–3 weeks and then go back to the maintenance dose. The base of linseed cake and rice bran is free from wheat and corn and gentle on the stomach, and because the snacks are ADMR-compliant, safe for competition, and have no withdrawal period, you can also feed them during tournament season. If your horse doesn't eat them, our 30-day satisfaction guarantee applies.

Because the best supplement is not the one with the longest ingredient list – but the one that actually gets into the horse.