When you groom your horse, watch his back—especially his lumbar area as shown here— for skin flickers or muscle flinches. These may indicate back pain of some type, which could translate to lameness.

Lameness can be definitively diagnosed only by your veterinarian, but the detective work of the diagnosis is best performed as a team. As owners and trainers, you can actively participate in detecting lameness, and these same skills are vital to monitor your horse’s recovery.

A prognosis for a full and speedy recovery often corresponds with diagnosing problems as soon as possible. So the ability to spot problems early on is crucial. Fortunately, many physical and attitudinal changes can tip you off to a possible problem. These are called nonspecific signs, and they can tell you that something is bothering your horse.

Nonspecific Signs
Nonspecific signs don’t tell you what is wrong with your horse, or even if it’s a lameness issue. They do tell you that it’s time to take action to figure things out. These nonspecific signs include the following:

• Personality changes. When something bothers your horse, his behavior may change. You may see grumpiness or irritability, a more subdued or withdrawn temperament, and even aggression. Any horse can have a bad day, but if these personality changes persist, take steps to figure out what’s bothering him.

• Decreased play and/or movement. If you hurt somewhere, you don’t feel like exercising either. Showing resistance or reluctance to move as usual is your horse’s way of telling you something’s wrong.

Decipher the Clues

Work with your veterinarian to form the perfect lameness detection team. Look for clues in both physical and attitudinal changes. These are called nonspecific signs, and they can tell you that something is bothering your horse. To detect where your horse may be hurting, start by looking at the whole horse first. By watching your horse move, the lame area may become apparent. Listen to your horse’s footfalls, which should sound equally loud and cadenced on a sound horse. You can detect lameness from the saddle by feeling disruption in your horse’s relaxed, even movement.

• Isolation from the other horses. If you notice your horse hanging off alone rather than with the rest of the herd, try to figure out what’s going on by bringing him in from the group for further checking.

• More or less lying-down time. If your horse is experiencing foot pain, you’ll see him perhaps spend more time off his feet and lying down. If the painful area is under more stress when he has to get up, then you may notice him not lying down as much.

• Change in appetite. Nagging pain may make your horse less enthusiastic about eating.

• Change in work ethic. Most horses look forward to being exercised. Always take any change in your horse’s attitude about work seriously. They’re not machines, and may vary a bit from day to day, but any obvious and persistent change is your horse’s way of telling you something is wrong. You may get further clues if there are specific things he’s unwilling to do as you work him.

• Changes in sweating, breathing, or pulse. If your horse sweats more than normal for the weather and level of work, suspect pain as the cause. He may also be breathing harder and have a higher pulse. These are all sensitive indicators of pain. (For a how-to guide to measure vital signs, see the January 2007 issue.)

• Passing more manure or urine than normal. This can be a sign of stress and pain. Horses with back pain or muscular hind end pain may want to defecate or urinate more than normal under saddle.

There are many potential causes for changes in personality, activity, or appetite, just as there are other explanations for changes you might see when you work your horse under saddle. These changes don’t automatically mean lameness is imminent, but they do mean you need to start working through the process of elimination. Next, I’ll tell you exactly how to do so.

Feel for tension or rigidity in your horse’s neck muscles. Neck pain can easily cause him to travel differently.

Look at the Whole Horse First
When you decide something is bothering your horse, take the time to look him over closely from head to toe. Observe him at rest in his stall and on turnout. Does he habitually point one front leg forward, or rest one hind leg more than the other? Does he stand with his elbows turned out? Does he stand with his toes or stifles rotated out behind? Does he stand with all four legs squarely perpendicular to the ground?

Starting at the head and ears, run your hands over your horse’s whole body and down each leg. When you run your hands over certain areas, note if he shrinks away, flicks his skin, pins his ears, kicks, etc. Check for any obvious swelling or heat.

Observe your horse from the front, sides, and back when someone is at his head and he’s standing squarely. Look for any differences in how well your horse is muscled from side to side. You’ll often see smaller, less well-defined muscles if there’s pain in the associated leg. Localized areas of muscle tension (muscles will feel hard) are also commonly found when a horse is hurting somewhere.

Check your horse’s feet. When there are longstanding painful conditions in a front leg, the hoof on the painful side will often be smaller than the opposite front. When painful conditions involve the front or back legs, you may see shoes/hoof walls wear more quickly on the comfortable side than the sore one, and wear patterns may be different.

Watch Your Horse Move
Watch your horse move in a circle, going both directions, first free of tack, then with tack but no rider, and finally tacked up with a rider. Lameness tends to be exaggerated when a horse is moving in a circle and is easiest to spot at the trot. If the tack itself is bothering your horse, you may be able to see this difference in how nicely he moves with and without tack, especially if you’re careful to tightly cinch the saddle.

Carrying a rider’s weight can worsen a horse’s lameness for several reasons:

• A saddle-fit problem may be made worse.
• More weight is put on the horse’s front legs.
• The hind end has to work harder to move weight forward.
• It’s difficult for the horse to make subtle changes in how he carries his weight.

First observe your horse at the walk. Does he look relaxed? Is he swinging freely through his back, shoulders, and haunches, and is he taking smooth, generous strides? Are his head and neck moving in rhythm with the walk? Are his ears pricked? Does he bend smoothly on the circle in both directions? Does he move the same in both directions? Observe the same things at the trot in both directions.

Then tack up your horse and note any differences with and without a rider. Horses that move in a stiff, wooden way are uncomfortable somewhere.

After observing your horse move on a circle, watch him from directly in front, directly behind, and from the side at both the walk and trot. Watch him on both a soft and a hard surface. From the front, check to see if he has normal head movements and if he’s landing evenly with his feet. Is he flexing his knees as high on both sides? Is he dragging a toe or stumbling?

From behind, watch his rump to see if it rises and falls equally from left to right. Horses with leg pain may transfer their weight to the other one quicker, making the hip on the painful side "hike" up higher. Check to see if the back legs move forward in a straight line, swing in before the foot lands, or swing outward before landing. Does the hock flex smoothly or with an obvious "wobble"?

Watch from both sides. Does your horse bring his hind legs forward so the hooves land in (or even beyond) the print of his front hooves? If not, he’s short striding behind. If only one leg is doing this, that’s usually the painful one. If both legs are doing it, then he may be painful in both hind legs or his pelvis, rump, or back.

Does your horse flex all joints evenly? Watch his fetlocks when each foot contacts the ground. Are they dropping the same amount on both sides? If not, he’s not carrying his weight evenly from side to side. The fetlock that drops the most is taking more of the weight.

After comparing left to right in both the front and back, compare the diagonal legs. A horse with a problem will often distribute more weight to the diagonal front or back leg. For example, a horse with pain in the left front may drop his ankle more in the right front and the right hind.

Your veterinarian is accustomed to palpating muscles, tendons, and ligaments in your horse’s legs to check for heat or pain.

Hear the Differences
Finally, learn to "see with your ears." When moving your horse on a hard surface, you’ll be able to hear subtle differences in how hard he’s landing. Close your eyes and concentrate on listening to the sound of his feet striking the ground. Each footfall should be as loud as the others, and you should hear an even rhythm.

You can hear many changes long before they can be seen. A softer sound will be heard when your horse isn’t putting full weight on a leg, and the sound that follows will often be louder. If the rhythm—that is, the interval between footfalls—has a "skip" in it, with a loud ground contact following quickly after a softer sounding one, that’s your horse hopping off a sore leg more quickly and shifting weight to another leg.

Clues from the Saddle
You can pick up important lameness clues when you’re in the saddle. Do you feel a relaxed sway at the walk or does your horse’s back feel rigid? If rigid, there’s pain somewhere. When you post the trot, does he throw you evenly on both diagonals? If not, the side with the weak thrust may be hurting. Does he take both canter leads evenly? If he’s resisting a lead, suspect the hind leg on that side. Reluctance to turn to either direction suggests pain in a leg to the inside of that turn.

The Feet
It has been estimated that 60% of all lameness problems originate in the feet. In fact, that’s probably too low a number. Unfortunately, you can’t check the internal structures of your horse’s feet for heat and swelling or pain on pressure like you can for the rest of the leg. Even hoof testers can give false negative results.

However, there are clues. As described earlier, look at how your horse stands and whether he habitually points a front foot. Also watch for frequent weight shifting up front. Look at the feet themselves. When one foot hurts more than the other, it’ll often be smaller. It’s also often more prone to thrush because the horse will try to avoid putting full weight on that foot. Bearing full weight on a foot forces manure and bedding out of the foot, keeping it cleaner. A narrower heel and frog are other signs of decreased weight bearing.

The Pastern
The back of the pastern should be smooth and tight, not puffy. Filling or edema can be caused either by inflammation in the foot or problems with the deep flexor tendon or the ligaments that insert on the back of the pastern. Look for both diffuse swelling and defined pockets of swelling or fluid as you travel up each leg. Also pay attention to any areas that feel warmer than the rest of the leg and warmer than the same area on the opposite leg.

Joint flexion tests and detailed palpation of tendons and ligaments really are best left to your veterinarian, who’ll have much more experience with a large variety of horses and how they normally react to the degree of joint tension or finger pressure used for those examinations. However, you often pick up your horse’s legs for routine tasks, such as cleaning hooves. Pay attention to whether he objects to lifting a particular leg for you.

How well your horse stands for the farrier is an even better test of the same thing. When a horse doesn’t want to pick up a leg, it’s often because either the opposite one hurts to stand on, or the one you’re asking for hurts when you flex a joint.

The Bottom Line
You don’t have to go to veterinary school to be an important link in keeping your horse sound. Paying attention to all the clues that indicate your horse may not be comfortable will make your riding partnership more enjoyable for both of you.