Question: My horse bowed a tendon last year. With stall rest, careful rehabilitation and some luck, he’s sound again and back in work. But his tendon is still very thick—there’s a distinct bulge just below his knee on the back of his leg. It’s not puffy or painful, but definitely bigger than the rest of his tendon. Our veterinarian did an ultrasound of the area and says it has healed well. But it makes me anxious to feel that lump every day. Will my horse always have a thick spot on his tendon?

Answer: I’m so happy to hear that your horse is recovered and sound. Owners often think tendon injuries are career-enders—and they can be—but given enough time and attentive care, many horses heal well enough to return to their previous activities.

The area of tendon that was damaged will likely never match the unaffected leg, although it will get better. Scar tissue, which is what “re-knits” the injured area of tendon, is denser and less organized than normal tissue. Over time, this tissue will continue to reorganize and refine— a process called remodeling—and feel more normal as it does. Tendons remodel slowly, however, so it will be a few years before you know what the final “scar” will feel like.

Assessing progress

To determine how close you might be to that point, you can apply a standing bandage or poultice to the leg overnight. If that does nothing to reduce the size of the tendon, the area consists of fully remodeled collagen that isn’t likely to reduce further. If bandaging or a poultice does bring down the size of the tendon, there is still fluid in the healing tissues, and you can continue to use wraps or poultice the encourage the area to tighten.

I would not recommend routinely wrapping or bandaging the area for riding. To heal properly, tendon tissue needs to bear the loads it will have to withstand under normal conditions. You could wrap the leg on those occasions when you’ll be asking for greater than normal exertion but protecting healing tissues so much that they never have to bear normal loads can be counterproductive.

Preventing reinjury

Anxiety about re-injury is understandable, but rest assured you’ll know if it happens. Instead of the firmness you are feeling now, there will be more heat and softer tissue in the area. The best thing you can do is keep your horse fit with regular, reasonable activities. At the same time, continue to feel that area of his tendon often so you are very familiar with his “new normal.”

David D. Frisbie, DVM, PhD
Colorado State University
Fort Collins, Colorado