Lameness is any abnormality in a horse's gait. It is an indication of a structural or functional disorder in one or more limbs of a horse that is apparent during motion or in the standing position. Another term for lameness is claudication.
What Causes Lameness?
Most often, lameness is due to muscle, joint or bone abnormalities. However, nervous system and, on rare occasions, circulatory system disorders, should be considered. In addition, lameness can be triggered by trauma, congenital or acquired abnormalities, infection, metabolic disturbances, circulatory and nervous disorders or a combination of these.
How to Diagnose Lameness
An important part of diagnosing and treating lameness is collecting a complete history of the horse. Veterinarians often have a good clue as to what lameness problems are likely to affect your horse by simply reviewing the animal's history. Here are some factors to consider in diagnosing lameness:
How a lame horse is examined depends largely on the type of lameness. Some lameness cases are easily diagnosed by history, presentation and a quick physical examination. However, other lameness disorders (often mild lameness), may require a lot of observation, joint flexion, palpation local anesthesia (i.e., nerve blocks), and in some cases radiography, ultrasonography, nuclear scintigraphy and other diagnostic modalities to diagnose.
In general, the lameness examination starts with a good look at the horse's posture and motion. After that, the sequence of events depends on the specific problem and the veterinarian's experience. The following sequence will vary from case to case.