Evaluate equine lameness objectively
How to judge a tricky problem with objective tools.
Dec 01, 2009
Along the way, a few things became apparent to me. First, it was rare that two experienced practitioners observed a horse in motion the same way, and they often had difficulty expressing exactly what they were observing. Second, disagreement on selection of the affected limb between my mentors was frequent enough to be confusing, at least to me.
Given the dedication and experience of my mentors, I knew the reasons for these observations were not likely due to deficient skills. Many veteran lameness veterinarians have since confided to me that they have made the same observations. They all reported having their share of confusing cases and believe there must be a better way.The art of lameness detection
Lameness detection in horses is difficult to master, and, until recently, the lack of ability to objectively measure lameness's effect on movement prevented standardization. Thus, when veterinarians were taught lameness detection in veterinary school or by mentors in their first years of practice, they were likely taught one of a myriad of different ways proposed either in text or tradition.
The human eye also has its physical limitations. Small changes in the movement of a body part due to lameness may be missed or misinterpreted by the limited spatial and temporal resolution of the human eye. And, as humans, we subjectively express how the lameness appears to us and can be biased. This is the art of lameness detection. But our art is more properly directed to unraveling the complexities and interconnectedness of anatomy, pathology, imaging, treatment and prognosis—in other words, the skills and knowledge that separate equine practitioners from the crowd.
The search for objectivity begins
However, distilling the published research down did not point to a reliable set of measures. An unreasonably large number of possible measures needed to be studied: stride length, stride timing, limb swing patterns, head and hip motion, and so on. What exactly were the best motion parameters to measure to detect lameness?