Why Does My Horse Stumble?

 
Possible Causes of Stumbling and Tripping
Does your horse stumble while you ride or drive it? All horses stumble occasionally just as we trip over our own toes sometimes for no reason at all. But sometimes stumbling is a sign of a physical problem.
Why Do Horses Stumble?
Horses can stumble or habitually trip for a number of different reasons. The most common reason is similar to why we take a misstep when the ground is rough slippery or uneven. Some horses are more trailwise than others and know how to keep their balance over rough terrain. Others have to learn this. There are several other factors that can cause a horse to stumble some more serious than others.

Fitness
If your horse is disinterested in his work or tired he may stumble. Muscle fatigue can cause stumbling and footdragging. This is more common in unfit horses or young horses. Young horses unused to carrying a rider may be unbalanced and stumble. This should stop once the horse understands how to balance the load he is carrying. 
Saddle Fit
Sometimes poorly fitting saddles can cause back pain that leads to stumbling. Poor saddle fit is responsible for many types of problems both physical and behavioral.
Training
Horses that travel with their heads up and backs hollowed may be more likely to stumble. If your horse carries his head too high he may not be able to balance or even see where to place his feet. Consider taking a few lessons to see if you can correct any bad habits you might have formed and learn to help your horse carry a rider comfortably. A martingale may be added to a horses tack for safety purposes to limit the extent to which a horse can raise its head and provide the rider with more control.
Conformation
Conformation dictates how your horse uses its body and legs. Some conformational defects may predispose a horse to stumbling. Long pasterns bench knees and other leg problems can cause a horse to be a habitual stumbler. 
Hoof Care
If the hooves are grown out too far or the toes are too long your horse may be tripping over his own toes. Have your blacksmith assess the angles he is trimming the hooves and the type and weight of shoes if your horse is shod. 
Serious Causes
More serious physical problems can include joint muscle and nerve damage such as
Arthritis inflammation inside a joint causing pain and