The athletic horse is subject to a variety of injuries and expresses the pain they cause in various ways, from behavioral quirks to obvious limping. Subtle lameness problems can be especially challenging to identify and manage. Fortunately, equine veterinarians have tools at their disposal to help them make educated clinical judgments about lamenesses, their structural causes, and prognoses.

Each year at the American Association of Equine Practitioners (AAEP) Convention organizers select a renowned practitioner to present the Frank J. Milne State-of-the-Art lecture on their topic of expertise. Sue Dyson, MA, Vet MB, PhD, DEO, FRCVS of the Animal Health Trust in Great Britain, who has devoted her professional life to the art and science of lameness diagnosis, was the distinguished lecturer at the 2013 convention, held Dec. 7-11 in Nashville, Tenn. She pulled from her experiences as veterinarian and accomplished rider to tackle this topic.

She prefaced her presentation with a quote from Sophocles: “Look and you will find. What is unsought will go undetected.” While this is true of life in general, she said, it is extremely appropriate to the process of working up a lameness in a horse.

Clinical Observations

Dyson prefers to apply a different lameness scale than the AAEP’s five-grade system. Using a scale of 0-8, she grades the horse at each gait, on different surfaces, and both in hand and under saddle. She recommended embellishing on each numeric grade with verbal descriptions.

During a lameness exam Dyson views the horse from the front, behind, and side. Next, she listens to the footfalls for gait irregularity,