Introduction to Splints on Horses:
One of the most common causes in lameness, especially in young horses who are just starting their working careers, is splints. Splints can occur to horses of any age though and there can be a number of different reasons why they happen. I’ve seen many horse owners fretting and fussing over a horse with a splint, but although they are uncomfortable for the horse, worrisome for the owner and inconveniently disrupt training or competition schedules they rarely cause a long term problem unless they are situated close to a joint or interfere with a ligament.
Metacarpal exostosis, Splints, ‘popping a splint’
The front canon bone is flanked by two smaller ‘splint’ bones which fuse into the canon bone as the horse matures. While the horse is still young, the splint bones are bound to the central canon bone by ligaments. As the horse matures, the ligaments ossifies—turns into bone, and all three bones become one. While the horse is young and the ligament is still flexible however, strain and injury can occur. The horse may have an injury from a kick or hitting the leg on another object or the injury may be the result of concussion from working too hard. Splints in horses and shin splints in humans are only vaguely similar as both involve strain to the ligaments, but humans can get shin splints any time during their lives as many joggers and runners will tell you and our shin bones don’t fuse to any other bones as we mature.
As the horse ages, and the bones securely fuse, there is less likelihood that they will develop splints. Usually by the time the horse is about four years old, the splint and canon bones will be one. There is a chance of reinjury if the horse's workload is too great.
If your young horse appears lame after you begin its training, it’s very likely a splint is the problem. As the horse trots, you will see it favor one leg and likely bob its head as it tries to balance itself to take some of the load off of the sore leg.
If you feel along the sides of the canon bone on the outside or inside, you will find a very sore spot that indicates the inflamed area. Heat and swelling well be present and the swelling might start to feel hard as the ligament calcifies. Because of how the leg bones are angled it is more common for splints to develop along the inside of the leg. It’s also possible for the horse to develop multiple splints, or one splint will be healing as another is beginning. Many horse owners will diagnose splints themselves, although if you’ve never dealt with splints before a veterinarian will help confirm the diagnoses and suggest treatment. Splint bones can fracture too and the symptoms are similar, so it’s important that you know what you are dealing with.
Your veterinarian will likely suggest that your horse be kept quite, with a short time of stall rest. Turn-out on soft surfaces will be best to prevent further injury from concussion. Your vet may recommend medications to help reduce the inflammation, and prevent excess calcification. Cold hosing and icing may help with inflammation. Many horse owners will let the splint heal without medication.
To prevent splints, a young horse should have its workload increased very slowly. Jumping, long fast distances over hard surfaces, fast stops and roll backs should be avoided until the horse’s bones have completely matured. Over-feeding, as is done with some youngsters headed for the show ring may make them more susceptible to splints. Good hoof care is essential as is good nutrition. Splint boots may help prevent a horse from hitting itself with its own hooves. This is more likely in youngsters who are unbalanced when first learning to carry a rider.
- Hayes, M. Horace, and Peter D. Rossdale. Veterinary notes for horse owners: an illustrated manual of horse medicine and surgery. 17th ed. New York: Prentice Hall Press, 1987. Print.
- "The Merck Veterinary Manual." The Merck Veterinary Manual. N.p., n.d. Web. 25 May 2012.