Splint Removal

By Heather Smith Thomas

Splints are unsightly and some people have them removed. Dr. Gary Baxter, Hospital Director at University of Georgia in Athens, Georgia, says splints are seen most often in younger horses when they start training. Stress may disrupt the interosseous ligament before it stabilizes. Subsequent bony enlargements may vary from pea-size to chicken-egg size. A young horse in training may “pop a splint”, with sudden swelling, inflammation and lameness—or develop a bony enlargement without history of lameness. The bony lump is usually just a blemish after the inflammatory stage is past.

A bony growth impinging on moving parts (knee joint, tendons or ligaments at the back of the leg) can be shaved off surgically. “If it is right up against the knee, you can’t take out all the splint bone because it helps support the knee joint, but a veterinarian can surgically remove part of it with a chisel and mallet and smooth it up, to make the horse sound,” says Baxter.

“The majority of splints don’t need surgery, and prognosis is usually good. With surgical removal, sometimes you get recurrence of bony growth because you’ve disturbed and stimulated bone-forming cells in the periosteum again. This causes it to create more layers of bone,” he says.

“Usually you don’t get as much bony regrowth as the original lump, so the surgery is still an improvement, if the lump was inhibiting a moving part. Generally, splints are more of an issue for show horses. Some owners want to remove a splint just to minimize the cosmetic blemish. The majority of splints I’ve removed were because they were causing lameness, or for cosmetic reasons. Either way, you can improve them, but for a show horse you have to worry about the hair changing color if you do surgery.”

Any splint can result in a bony lump, or temporary thickening of the periosteum and the ligament. “Even if it’s not bony, it might be a soft-tissue fibrous enlargement in that area. This may resolve with time, but if it is re-injured it could revert back to inflammation and create a bony enlargement as well,” says Baxter.

“Repetitive injury and inflammation result in bony enlargement. Many horses have bony enlargements under the knee, on the inside of the leg, but if these chronic splints don’t bother the horse, they don’t need treatment. The horse may have been a little lame at first, or had some inflammation and then it quiets down and doesn’t cause any problems,” he says.

“First aid treatment when the horse goes lame with heat and swelling in that area is to decrease the inflammation. Many people cold hose or ice the area or use devices that provide cold therapy/compression and/or non-steroidal anti-inflammatory therapy. Topical anti-inflammatories like Surpass or diclofenac liposome cream work well. Traditionally, we used DMSO on this type of injury, often with DMSO and glycerin in a sweat. This counter-pressure is helpful, wrapping the area. The more you can decrease the inflammatory response, the less likely the injury will result in bony enlargement.”

“For bony lumps that still have inflammation some people try shock wave treatment to try to reduce inflammation in the ligament itself, which could be beneficial. This type of treatment is controversial, however. Some people feel the shock waves actually stimulate the periosteum, which could result in more bone growth,” he explains.

Some people try counter-irritation in the acute stage–local injection of a steroid along the ligament, to knock out the inflammation. “The steroid may contribute to bony growth, however. A small dose, given just once, may help. You don’t want repeated injections because this is usually counterproductive. Some people use things like therapeutic ultrasound, cold laser therapy, etc. to try to reduce inflammation, but cold therapy, topical anti-inflammatory medication, and rest, are generally adequate and effective,” explains Baxter.