You run your hand down the leg after work and there it is: a tendon that feels thicker than normal, sometimes warm, sometimes sensitive. A tendon injury (damage to a tendon in the leg) is one of the most feared problems in sport horses, not because it's immediately life-threatening, but because recovery takes months and easily goes wrong. This guide helps you recognize what you're feeling, what to do right away, and what a realistic recovery looks like — the diagnosis and the rehabilitation schedule always belong with the vet.
What a Tendon Does and Why It Gets Damaged
The tendons at the back of the lower leg connect the muscles to the bones and absorb an enormous load with every stride. They work like a kind of spring: they stretch and return energy. That makes them strong, but also vulnerable. A tendon has little blood supply, which is exactly why it heals slowly.
The best-known injuries sit in the flexor tendons at the back of the cannon bone and in the suspensory ligament (the musculus interosseus), which runs along the back of the cannon bone. Damage rarely results from a single misstep; it's usually building overuse — a lot of work on hard, or on deep, footing, fatigue at the end of a training session, or small bits of damage that accumulate until a fiber tears. A bad landing after a jump or a slip can be the last straw.
Feeling the Leg: What's Normal, What Isn't
To recognize abnormalities, you need to know what your own horse's legs normally feel like. So regularly run your flat hand and fingers along the tendons at rest, on both sides, and compare both front legs with each other.
Signals that can point to a tendon problem:
- Swelling at the back of the cannon bone, often described as a "bowed tendon" because the tendon bows out backward
- Heat in the leg, noticeable when you compare it with the other side
- Sensitivity or pain when you press gently on the tendon; the horse pulls the leg away
- Lameness, from barely visible to clearly refusing to bear weight
- Swelling that gets bigger after work, or doesn't go down after a night in the stall
Not every thick spot is a tendon. Swelling at the front of the joint, a filled tendon sheath without heat or pain (a "cold windgall"), or fluid in a sheath can be something else entirely. That's why feeling alone isn't enough for a diagnosis — see also lameness in the glossary.
Act Immediately: Cooling and Rest
If you suspect a fresh tendon injury, the first hours count. Your goal is to limit the inflammation and swelling, not to cure it yourself.
- Stop working. Put the horse in a stall or a small space. Continuing to ride or "walking it off" demonstrably makes fresh tendon damage worse.
- Cool the leg. Cold running water from a hose for about 15–20 minutes, a few times a day for the first few days, limits the swelling. Cooling clay or a gel can help in addition.
- Give rest and support. A stable bandage can limit the swelling, but a badly applied bandage does more harm than good. Only apply one if you've been taught how, or let the vet do it.
- Call the vet if the swelling is warm and painful, the horse is lame, or the thickness hasn't gone down after a day of rest. Don't wait too long on this — early imaging determines the prognosis.
- Don't give anti-inflammatories or painkillers on your own initiative. They mask precisely the signal that the horse needs to rest. Only on the vet's instruction.
Better to call once too early than to let a fresh tendon get worse because you "waited to see how it went."
The Diagnosis: Why an Ultrasound Is Crucial
With your hand you can feel that something is wrong, not how badly. The vet assesses the lameness and will almost always make an ultrasound of the tendon. That shows which tendon is affected, how extensive the damage is, and how many fibers have torn. That image is the basis for the prognosis and the recovery schedule.
An ultrasound is usually repeated after a few weeks. The initial swelling actually says little about the real damage; sometimes a leg that looks bad turns out fine, sometimes there's a sizeable tear behind a modest lump. The build-up schedule is calibrated to those follow-up scans. Never progress faster than the images allow, no matter how sound the horse looks — a tendon often feels and looks recovered while the tissue is still fragile. For the exact assessment and schedule, the vet is the only right source; you can also find details through your treating vet or knhs.nl for the competition framework.
Riding Out the Recovery: Months, Not Weeks
This is the part owners underestimate. Tendon tissue heals slowly, and the new tissue has to be made load-bearing gradually, or it tears again. Don't count on weeks but on months, and with a severe injury, on a year or more before the horse works at its old level again.
Recovery broadly runs through phases. The duration of each phase depends on the severity and what the ultrasounds show:
| Phase | What Happens | Rough Duration |
|---|---|---|
| Rest / inflammation | Stall or small paddock rest, cooling, no work | a few weeks |
| Controlled walking | In hand or under saddle, building up in time | several months |
| Building up trot and work | Step by step, more load, guided by ultrasound | months |
| Back to full work | Careful resumption of the old level | up to a year or longer |
The hardest part is often stall rest with controlled movement: a fit sport horse that isn't allowed out, but does need exactly the right dose of movement for the tendon to heal in an orderly way. Too much is harmful, too little as well. Stick strictly to the minutes your vet prescribes and don't increase it by feel.
Preventing Another Injury
A previously damaged tendon stays a weak spot; re-injury often happens when the build-up went too fast. You can reduce the risk, not eliminate it.
- Build up work and fitness gradually, and stop a training session before the horse is truly tired — fatigue is a major risk factor.
- Watch the footing: avoid prolonged work on hard, or on deep, loose ground.
- Warm up properly and cool down at a walk, so the tendons aren't loaded heavily while still cold.
- Check the legs after every solid training session, so you notice early swelling early.
- Make sure trimming or shoeing stays balanced and regular; uneven hooves shift the load on the tendons. See also tendon boots in the glossary.
In Short
Learn what your own horse's legs normally feel like, so a thickened or warm tendon stands out immediately. Stop working if you suspect anything, cool the leg, and call the vet for an ultrasound — that determines how bad it is and what the recovery will look like. The hardest part is the patience: a tendon heals over months, and building up too soon is the main cause of re-injury. Follow your vet's schedule strictly and let the pace be set by the ultrasound, not by how good your horse feels.
See also: Recognizing Colic and Other Emergencies in Horses · Which Insurance You Need · Glossary of terms