Lameness will likely be a problem for all horse owners at some point. It is a sign that a horse has an injury that causes pain when it moves or places weight on the affected leg. If the cause of lameness is apparent, you may be able to administer first aid. If not, confine the horse to prevent further damage to the leg and call the veterinarian if mild lameness persists. Horses with severe lameness need prompt veterinary attention, as they are usually experiencing significant pain.
Most lameness affects the forelimbs, and 90% of problems occur in the knee and below. In the hind limbs, 80% of cases of lameness involve the hock or stifle. Lameness frequently occurs in the feet, so carefully examine the hoof in cases of sudden-onset lameness. Common foot lamenesses include abscesses and sole bruises.
Different breeds and disciplines have different predispositions for lameness. Standardbreds are predisposed to hock problems, and Quarter Horses are predisposed to ringbone. Racing predisposes horses to knee chips, whereas trail riding often leads to stone bruises in the hooves. Horses worked on hard surfaces are more likely to have navicular disease. Some problems that affect young, growing horses, such as shin soreness or locking patellas (knee caps), rarely trouble adult horses.
Any signs of lameness should be investigated immediately and any hoof or foot problem treated correctly. The lameness may need examination and treatment by a veterinarian, a farrier, or both.
Make a habit of regularly handling your horse’s legs and feet because then you will notice any abnormality such as swelling or heat. Never neglect cracks, wounds, or punctures to the feet.
A lame horse may have a shortened stride, feel uneven when ridden, or nod its head when trotted. If the horse is trotting on a hard surface a difference may be heard in the way the horse puts the hoof to the ground when bearing weight on the lame leg.
A common diagnostic tool used to evaluate hind limb lameness is the flexion test. To conduct the test, a veterinarian grasps the pastern of a horse’s hind leg and flexes the leg upward and forward as much as possible, holding the flexed position for up to 60 seconds. After the veterinarian releases the leg, the handler immediately trots the horse forward. Lameness that may have been hard to see before the flexion test is more easily observed as the horse moves out after having its leg tightly flexed.
In reality, it’s not uncommon for horses to fidget so much that the veterinarian has to release the leg in the middle of the test, or the horse refuses to trot out briskly after the test. Instead of being helpful, these results are stressful for the horse, owner, and veterinarian.
Research was recently conducted at Kansas State University to determine whether veterinarians were able to tell more about a horse’s lameness when leg flexion was held for either five seconds or 60 seconds.
Experienced veterinarians viewed videotapes of 34 horses, some of which were sound while others had varying degrees of lameness. Horses shown in the videos underwent either five or 60 seconds of leg flexion. Results showed that determinations of lameness agreed in about 75% of cases, regardless of how long the leg had been flexed. This suggests that longer periods of flexion might not yield more information about a horse’s status than shorter periods. The researchers suggested that veterinarians might consider using shorter flexion times in lameness exams and evaluating whether this change makes any difference in finding a diagnosis.