What are Splints?
Splints in a horse is an inflammatory condition of the splint bones that mainly happens in horses that are growing and participating in significant training.
Each of a horse’s limb contains a cannon bone; on each side of the cannon bone is a small bone called the splint bone. About two thirds of the way down the cannon bone, the splint bone, which is thin, tapers and becomes a small knob. In between the splint bones and the cannon bone there is the interosseous ligament which consists of connective tissue that will become bone once the horse is around 3-4 years old. Injury to this ligament or to the soft tissue that covers the splint bones or the bones next to them will be diagnosed as splints, which start as soft tissue swelling and will become bony swellings.
An inflammatory condition of the splint bone or the ligament adjacent to it, splints occurs in young horses and present with swelling and pain along the splint bone.
Book First Walk Free!
Symptoms of Splints in Horses
Should your horse be experiencing splints, you may witness lameness (usually mild) that is most apparent when your horse is either trotting or working or not long after he has finished doing so. The lameness he is displaying may be intermittent or ongoing for up to 12 months and will be more apparent when he is exercising on hard ground.
If your horse has splints, he will likely flinch when the part of the ligament that is affected is touched; there may be a large swelling or multiple small swellings along the splint bone resulting from ossification. You may feel heat along the splint bone. Once the ligament turns into bone the swelling and soreness are usually eliminated.
Four types of splints are discussed:
- True splint - A fibrous and bony growth at the space between the bone and ligament in addition to inflammation or a tear in the ligament
- Blind splint - Inflammation caused by this type of splint leads to a fibrous and bony growth in between the splint bones and suspensory ligament; little to no external swelling will be seen
- Periostitis - Inflammation and bony reaction as a result of trauma to the soft tissue that covers the bone
- Knee splint - Swelling occurs at the upper part of the splint bone, close to the knee and involves the lower joint. This will lead to osteoarthritis
Causes of Splints in Horses
In young horses, a ligament that exists between the cannon bone and the splint bones is very elastic. Upon the horse maturing, the ligament begins to be replaced by bone and then all three bones will fuse together. While this process takes place, a horse may experience swelling and pain. Should the horse be involved in jumping, running and working during the years where this process is occurring, further irritation can be experienced.
This condition occurs most often in 2 to 3-year old horses and more rarely in horses aged 4 and 5. Splints are more commonly found to be experienced in the front limbs and rarely are experienced in the hind limbs. Most splint issues happen on the inside of the front limbs; most often impacted is the medial splint bone because its surface is more slanted. When weight is placed on the bones of the horse’s front legs, it is thought that the medial bone will hold greater weight than the lateral splint bone, causing the ligament that is between the medial splint bone and the cannon bone to experience greater strain than the ligament adjacent to the lateral splint bone.
Direct trauma (like a kick to the leg), conformational anomalies, mineral imbalances and over nutrition can also lead to the condition.
Diagnosis of Splints in Horses
Your veterinarian will conduct a physical examination of your horse and ask you for information regarding the symptoms you have seen in him, when you first noticed them, and what changes in the symptoms have occurred. Upon observing the swelling and noticing that your horse feels pain when the area is touched, your veterinarian will consider that he is experiencing splints. Radiographs will likely be utilized in order to confirm the diagnosis, get an idea of the size of the bone growth, and determine if there is a fracture to the splint bone. In some cases, an ultrasound will be used if it is thought that there could be injury or impact to the suspensory ligament.
Treatment of Splints in Horses
There are a variety of methods that are used for treating splints in horses. It is important for your horse to rest and you should provide a place with soft ground for him to reside for a minimum of 30 days. Topical cold therapy (for example, ice or cold hosing) may help to decrease the swelling and inflammation. Pressure bandaging may be utilized to reduce the swelling. Medications like NSAIDs and topical anti-inflammatories like dimethyl sulfoxide may be used that will help decrease the inflammation your horse is experiencing as well as stop there from being too much bone growth. Corticosteroid injections may also help with reducing swelling. In some cases, the condition may resolve itself without treatment.
In cases where the growth of bone is very large, it can get in the way of your horse’s knee joint. Should this occur, surgery can be considered to help resolve the issue.
Recovery of Splints in Horses
Should your horse be experiencing splints, the condition is curable and the prognosis is good too excellent in most cases. You can reduce the risk of splints in your horse by decreasing the intensity and frequency of his work as a young horse, ensure he receives proper nutrition and is a healthy weight, provide proper foot care and use protective splint boots should there be limb interference.