Foal splints for contracted tendons

Over the last 35 years of producing and raising over 180 foals and thousands of lambs and goat kids, I’ve developed a reusable, washable, inexpensive, yet effective, splinting design for newborn foals with contracted front tendons. We produce 15-20 foals annually and there’s typically one foal each year that can benefit from having a front leg splinted for the first day to 5 days of life. This is all the time that it typically takes for the tendons to stretch so the hoof is flat on the ground.

Foals receive splinting if a front fetlock joint is knuckling over and creating instability with standing and nursing. When that joint is stabilized, the foal can easily move with the herd on pasture, get up and down with ease, and be stable for nursing. Keeping the foal and mare out with the herd is a priority for us, since it reduces stress and encourages that joint to be used and stretched more than would happen if the foal was stalled. Below is my current and preferred design for foals.

The above photo shows my current and preferred setup. Note the 1.5″ wide black hook velcro straps that pass through the slits in the splints, with the hooks toward the leg/polo wrap, and pass around the front of the polo wrap, forming an X, before the Flagbands (dairy cow leg bands) are applied tightly over the fetlock joint, at the top of the splint, and below the fetlock joint. That black hook velcro connecting with the polo wrap layers is what holds the splint down, as the foal walks around. If it wasn’t there, the splint would ride up and push into the knee joint, where it won’t do the job of stretching the pastern tendons.

The goal with splinting is to stabilize the joint, help stretch the tight tendons, and not compromise blood flow or joint integrity in the process. Most foals with contracted tendons get exhausted faster and sleep longer than foals that don’t struggle to stand and nurse. While the foal sleeps, I apply the splints. No sedation is needed.

The leg is first wrapped with vet wrap, which prevents the next layer, the polo wrap, from spinning around the leg. The vet wrap should be loose enough to slide a finger under. Too tight will cut off blood flow to the skin and hoof. I apply the vet wrap from below the knee joint to just below the fetlock joint.

The polo wrap should be applied snugly, but again, not too tight. It shouldn’t move when applied tightly enough. If it can be twisted, it’s too loose. I apply the polo wraps up to the base of the knee and down to the coronet band. I wrap such that each layer covers half the width of the prior layer, to apply padding evenly.

I check the splints in a half hour after I first apply them. I want them to:

Have stayed in place as the foal gets up and down and walks around. The splints shouldn’t swing around to the front of the leg, nor should they have slid up the leg.
Be very snug over the fetlock joint, to ensure the toe can’t knuckle over anymore.
Be snug over the pastern to prevent knuckling over.
Be loose enough that there is warmth when I stick a finger between the back of the frog and the splint wadding. If the leg is cool or cold, some part of the splinting is too tight and needs to be redone to allow better bloodflow. You may need to redo it from the vetwrap base layer, depending on which layer was applied too tightly. This is something you learn by doing and checking.

I’ve tried many different supplies and materials to achieve these goals, and settled on the following reusable items:

Supplies for one splint:

Vet wrap
Scissors for cutting the vet wrap to length, and for cutting the vet wrap off the leg when the leg is corrected.
Polo wrap with velcro closure. The blue polo wrap is full length. The black polo wrap has been cut in half, and provides sufficient padding for the legs of our Fjord foals. Bigger boned horses or calve would benefit from the full length polo wrap.
11 inch long section of 2 inch diameter PVC, split in half, edges and corners ground round, slits ground in upper 1/3 of splint.
18 inch long hook velcro, 1.5 inch wide, for securing the splint from shifting up toward the knee joint.
Gorilla tape for attaching wadding to the lower 1/4 of the inside of the splint.
Wadding (I use previously used vet wrap) to help push on the heel bulb, to encourage the hoof to stretch forward of the cannon bone.
Flagbands or 12 inch 2 sided velcro strips to apply pressure where needed on the leg in the splint.
All of these items were available at my local Farm and Fleet farm store.

Splint Length:

I designed these splints for Fjord foals. The mature height of the foals is between 13.3 hands and 15.1 hands (55″-61″ mature height). An 11 inch tall splint works for this foal size range. To measure the length for any particular foal, measure from the heel edge to 2″ below the tendon insertion into the back of the knee (the superficial and deep digital flexor tendons). The top edge of the splint should never rub where that tendon attaches to the knee joint. In this photo, the polo wrap padding is not on the near leg, to show the placement and length of the splint relative to the leg length.

Splint Diameter: Our foals have cannon bones that range in circumference from 13 cm to 15 cm. Calves or horses with heavier cannon bones and bigger joints will need PVC splints made from 3 inch to 4 inch diameter PVC, split into thirds, rather than halves. The splint edge should not touch the fetlock joint when the splint without any padding is held up against the back of the leg. A 2 inch diameter PVC pipe might be too curved to accommodate larger fetlock joints appropriately. The velcro hook piece will need to be longer than 18 inches for a larger boned animal to be splinted securely.

I use the Gorilla tape to secure a ball of used vet wrap in the lower 1/4 of the splint, to push the heel bulbs forward. The Gorilla tape is more durable than duct tape when the foal is walking on that bottom edge of the splint.

I’ve had some foals that needed more than the basic level of heel bulb pushing, so I’ve added a slip-on version of wadding padding that is removeable, but that adds the needed depth of padding. I use vet wrap to hold it in place.

Also, note the 18 inch long hook velcro strip that is passed through the slits in the splint, with the hooks toward the leg/polo wrap. This is part of what secures the splint from shifting up the leg.

The desired results:

Photo of tendons that are sufficiently stretched out that the splints are no longer needed.

Note that this splint did not have the 18 inch long loop velcro crossed over the front of the polo wrap, so you can see that the splint shifted up and could rub on the back of the knee. This is not a desirable application of the splint. Including the loop velcro cross piece stops this from happening.

Removing the PVC and watching how the foal moves without the splint support is a good way to assess whether further splinting is needed. This foal is stretched out well enough to no longer need splints.

If 5 days of splinting has passed, the foal is nursing well, IgG is good, and the toes aren’t stretching out, then an IV dose of 10 mL of oxytetracycline is something that your vet might recommend to facilitate tendon loosening. Talk to your vet. Most of the time, the oxytet is not needed and the tendons will stretch with splinting alone.

If applied correctly, the splint design I use stretches the pastern and lower tendons to allow the hoof to stop knuckling over. There may be a little swelling from the pressure, but there should not be pressure sores created by this splinting.

If sores are created, a follow-up application of a sugar pack will provide an inexpensive dressing that prevents bacteria from growing, kills any existing bacteria through osmotic pressure change (no antibiotics are needed), doesn’t cause proud flesh, creates natural debridement, and keeps the area moist for quick tissue healing.

If the wound is above the pastern, I apply sugar with a disposable infant diaper wrapped sideways around the area of dead skin, secured at the bottom with vet wrap, then I pour white granulated sugar into the funnel made by the diaper, and then vet wrap on the upper leg side to hold the sugar in. I then vet wrap over the whole diaper area to provide support for the weight of the sugar, and the wound exudate fluid that will seep into this dressing. I replace the dressing daily. I don’t wash it or debride it, since neither of those treatments are needed with sugar packing.

If the compromised tissue is below the pastern, I use a rubber treatment boot of the right size, filled with sugar and a little water added to make it soupy. I use vet wrap to hold it on while the foal remains part of the herd on pasture. This also works for other non-fungal microbial infections of the hoof or coronet back (abscesses, injuries, etc).

Sugar as a wound dressing has been used for decades, is validated in the scientific literature for its healing abilities and antimicrobial nature, and it’s really inexpensive. Iodine is not needed and can delay wound healing. Honey works but is sloppy and much more expensive. Most other treatment substances are more expensive than plain white sugar, disposable diapers and vet wrap.

I have many splint prototypes that I’ve tried and discarded over the years:

I tried neoprene splint boots with padding, and they were not stiff enough. They were also really hot.

I tried using washable dairy towels as the padding, and vet wrap over the padding, then over the splinted leg. This did not have a base layer of vet wrap on the leg, and did not prevent the splint and padding from rotating around to the front of the leg. The dairy towels were hard to apply without wrinkles and evenly. Polo wraps were much better. Vet wrap around the outside of the splint took longer to apply, used more disposable product, and was harder to remove to check the splints than using the dairy Flagbands to secure the splint in place.

To deal with the splints spinning to the front of the leg and not providing the needed support, I tried attaching 2 splints on each leg, which is similar to the Redboot design, but this didn’t provide the needed support and it didn’t stay in place. It is also unnecessarily complicated, based on what I currently use.

I also tried a full round of PVC, with straps over the withers to hold it up, and foam padding at the top. This is similar to the Redboot design, but it was too sloppy and didn’t provide the constant stretching and support of my current design.

I tried 3 inch diameter PVC, cut in thirds and edges/corners rounded, but this was too big for the size of legs of our foals. Even with vet wrap as the base layer, these were too wide to secure in place and they spun around the leg.

Taping with Gorilla tape, a wadding of used vet wrap that is soft but won’t squish down flat, where the heel bulb needed support to be pushed forward is a design that is successful.

I tried providing a flat base to encourage the hoof to stretch forward. This didn’t work. The ground piece caught the grass and tripped the foal too much. Also, the fixed flat surface wasn’t as effective at stretching the pastern tendons as compared with a splint along the back of the leg that extended down to just the base of the hoof heels, where every step provides dynamic ground interaction that is needed to help the tendons stretch.

I also used sand in a cast iron skillet on the stove to heat up the PVC, and used the shoulder of a wine bottle to curve the top of the hot PVC out, in an attempt to reduce potential for rubbing on the back of the knee or tendons there. This was not necessary.

I tried various ways of shaping of the splints with heat from hot sand in a cast iron skillet. None of this was as good as just cutting straight PVC, rounding the corners and edges, making slits at the top for securing it from sliding up, and providing the vet wrap base with polo wrap padding, then holding it in place with Flagbands.

Citation:
Nolden, C.A. 2026. Foal Splints for Contracted Tendons. 1dr Acres Farm website. https://www.wonderacresfarm.com/foal-splints-for-contracted-tendons/. Published 7/20/2026.

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