Lameness is one of the most common problems every horse owner faces from time to time. In most cases, it is only temporary lameness, caused by a hoof abscess or a stone in the shoe. Once the cause is remedied, the horse returns to normal. In other cases, lameness becomes chronic, requiring special shoeing or other treatments to keep the horse serviceable to ride. In the worst cases, lameness may result in having to put down the horse when the pain cannot be managed.
The causes of lameness can be external or internal. The problem usually arises in either the leg or the foot, but it can also come from the shoulder, spine, or other areas. In some cases, lameness disappears on its own, and you may never know exactly what caused it. When the cause isn't obvious, diagnosis can sometimes involve a lot of guesswork.
Common lameness problems are typically seen in horses subjected to a lot of foot and leg stresses from racing, changing direction abruptly, or jumping. It's also more common in overweight horses or certain breeds like the American Quarter Horse that have been genetically manipulated to have heavy, muscular bodies supported by small legs and tiny feet.
If a horse suddenly becomes lame, the first place to look is the foot. Check the foot on the lame leg for a nail, stick, or stone. If nothing is readily visible, check the rest of the leg for tender spots, swelling, or warmness, all signs of inflammation. At the tender site, look for an abrasion or puncture wound. An abrasion would probably have to be significant and, there fore, very visible to cause lameness, but puncture wounds can be extremely deep and hard to detect. A puncture wound as high as the shoulder could cause lameness as well.
Navicular disease causes changes in the tissues and supporting structure of the small navicular bone in the foot. Repeated concussive injuries and metabolic disturbances are the most common causes of the permanent damage. The horse's conformation can predispose him to navicular disease if he has too-short pasterns, too-straight shoulders, or too-small feet to handle the concussion on the navicular bone.
A farrier can help make the navicular horse more comfortable with corrective shoeing. Medications exist to help manage the pain. Although some horses can still be used after they develop navicular disease, their use is often limited to light riding.
A navicular horse is considered unsound. Afflicted horses tend to shorten their stride and move off their toes to escape the pain in their heels. This causes them to stumble more, some so badly that they become unsafe to ride. The toes of the shoes on a navicular horse will wear down more quickly then the heels. X-rays of the feet performed during a prepurchase exam are done to rule out the presence of navicular changes deep inside the hoof when outward signs are not readily apparent.
You may witness your horse fall, get a leg caught under or in a fence, or slip getting out of the horse trailer. The injuries sustained in such accidents can cause lameness ranging from mild to serious, but at least you know what caused it and can tell your vet what happened.
Minor lameness from such mishaps is fairly manageable. Aside from treating any obvious cuts or swellings, a veterinarian will often administer phenylbutazone — commonly called “bute” — an anti-inflammatory pain reliever, for a few days to help relieve the horse's pain.
Be careful when using bute or other pain-masking drugs. They can make the horse feel good enough to move around too much, perhaps causing added damage. If the horse can remain calm in his stall for a day or two, bute combined with limited mobility may be all that is needed to help a minor problem resolve itself readily.
Sometimes a horse steps on a stone and bruises or cuts the sole of his foot, which will make him sore for several days or weeks. These injuries aren't always so readily evident, and your vet or farrier may need to pull off the horse's shoe and scrape around a bit to find the cause.
If the horse throws a shoe out in the field and rips off part of the hoof with it, he may be lame until his foot has time to grow out again. Some horses tend to go temporarily lame right after being shod. Such cases often resolve themselves in a day or two. Sometimes, however, the farrier may accidentally “quick” the horse with a horseshoe nail. Removing and resetting the nail properly usually resolves the problem.
Sometimes a horse comes in lame from the pasture with no outward signs of kicks, knicks, cuts, bites, or other trauma. You'll see this most often with hoof abscesses. A horse that goes suddenly dead lame with only three good legs to stand on but with no signs of fracture, sprains, or swellings probably has a pocket of pus inside a foot. Try soaking the affected foot in warm water and Epsom salts to help relieve the pressure, and give your vet a call. Avoid giving bute in these instances, as you won't be able to tell whether the horse is improving because the drug masks the pain and symptoms.
To pinpoint lameness problems, your vet may want to administer a nerve-block test. This diagnostic tool numbs an area of the leg to see if the lameness disappears when the horse cannot feel pain from the affected area.
Lameness is a serious issue under the best of circumstances because it compromises your use of the horse. When you have no idea of the cause, getting your veterinarian on the scene as soon as possible can make the difference between a short-term layoff and chronic lameness. Your vet may want to take X-rays or perform a nerve-block test to zero in on the real issue.