The Very Young & Very Old
Horses who are just starting under saddle and are under the age of 3½ to 4 years old are still in the process of strengthening their ligaments, tendons, bones, and joints. Exercise remodels these structures so they are better able to withstand exercise, but young horses are easily injured until their
structures are strengthened. However, their muscles, hearts, and lungs become conditioned much more quickly, which means your youngster could be overloading his skeleton before he shows you much along the lines of fatigue. Lots of miles at slow speeds is the proper foundation for a young horse.
Older horses have a different set of problems to deal with. Their heart and lung function may not be as good as in their earlier years, and most horses accumulate one or more arthritic joints or injuries in their lifetimes. If you take things slow, the regular exercise should actually lead to significant improvements in their endurance, flexibility, and comfort. If this isn't happening, it's time to involve your vet to form a game plan.
Stay Clear of Splints
The splint bones are two long, slender bones running down the back of the horse's cannon bone. They are remnants from the days when horses had more than one toe. The medial (inside) splint bone forms part of the lower joint of the knee. Before the age of 4 or 5 years old, the upper portions of the splint bone are held to the cannon bone by a ligament. After this age, the ligament turns to bone. Because the top of the medial splint bone helps bear weight, when a young horse is moving, this force tends to push the splint bone out and stretch the attaching ligament. Over time, it is this tension that stimulates the ligament to calcify and form a tighter attachment. However, if you overdo exercise-either too long or too fast-a young horse can end up with too much strain in this area, resulting in inflammation and swelling that is commonly called a "splint."
Horses whose cannon bones are offset to the outside or twisted in any way are also more prone to developing splint problems, and so are horses with improper amounts or balances of minerals in their diets. To minimize the chances of this problem developing, always introduce exercise to young horses very slowly, especially if their front leg conformation is less than perfect. Feed a diet with correct amounts and balances of minerals for a growing horse. Check the splint area regularly and stop formal exercise at the first sign of heat or swelling. Aggressive treatment with ice packing and/or boots is the best way to control the inflammation.
