The In’s and Out’s of Popped Splints

My young two year old warmblood has very small splints on both front legs. There is one on each leg up front. I am wondering if those splints will grow over time when he is being jumped and worked on the flat. If so how do I help them heal or take care of them now? OR, Indiana

Dear OR,

First of all, let’s make sure everyone is on the same page with us. The splint bones are the small bones on the inside (medial) and outside (lateral) of the cannon bone. In the front legs, the inside splint bone is called the second metacarpal and the outside splint bone is called the fourth metacarpal. In the hind legs, the term metaTARSAL is used. The cannon bone itself is the third metacarpal/metatarsal. The splint bones begin just below the knee, where they are largest, and extend almost to the ankle or fetlock, where they taper to a “button.” Splints are believed to be the remnants of second and fourth toes, but now have only a supportive function.

When a horse “pops a splint,” it means something has caused pain, heat and swelling in the area of the splint bone. Splints can be caused by direct trauma, overtraining, conformation or shoeing that leads to interference; being overweight; or even being malnourished. The swelling can be inflammation of the ligament between the splint and the cannon bone, inflammation of the outer layer of the splint bone itself, or both. Some horses become lame but many do not. A popped splint can be the size of the end of your thumb, or more than twice that large. Generalized swelling may indicate a more severe problem than a popped splint, such as a fractured splint bone, and a veterinarian should be contacted for an accurate diagnosis and appropriate treatment. Splints usually occur in the front, usually on the inside, and usually in young horses. And usually, they go away on their own with minimal help from us: cold therapy, bandaging (with or without sweating), anti-inflammatory medications, supplements that support normal healing, and rest. However, you are right to be concerned about future complications because some splints do recur, making training and competing very frustrating for owners.

Dr. Larry Bramlage, a prominent veterinary surgeon at Rood & Riddle Equine Clinic in Lexington, KY, and past president of the American Association of Equine Practitioners, tried a new approach on splints that kept recurring once the horse was put back into work. His team found that if the splint “pops” in the bottom two-thirds of the bone, there may be too much movement for the splint to heal normally, that is, by laying new bone between it and the cannon bone. Instead, in some situations, the best results may be obtained by surgically removing the bottom of the splint bone (when a splint bone fracture occurs in the bottom two-thirds of the bone, it is also surgically removed.)

Now, I’m not telling you this is what needs to be done in your horse. This is a last-resort method to allow a horse to continue training and competing pain-free. You should follow your veterinarian’s advice for the splint your horse has, and take as much time as he needs now, at two years of age, for it to heal completely before going back to any work (lunging, backing, ponying, etc.) I would like to share something my local veterinarian told me about healing splints though: do what the Amish do and roll a corn cob (minus corn kernels) over the splint for 10 minutes twice a day to stimulate healing!