A wireless, inertial sensor-based system can effectively measure a horse’s response to a flexion test, according to a research study conducted by orthopaedic surgeons based at Glasgow vet school.
A comprehensive study conducted by orthopaedic surgeons based at the University of Glasgow’s School of Veterinary Medicine has shown that a wireless, inertial sensor-based system can effectively measure the horse’s response to a flexion test.
Flexion tests are used routinely in horses with subtle or imperceptible lameness, to exacerbate the problem and make it apparent to the observer. A short period of pressure is applied to the joints of the limb before re-examination, and any change in gait is evaluated.
However, flexion tests rely on the ability of the observer to identify and interpret changes in the horse’s gait and in that respect these tests are subjective and not necessarily consistent between observers.
However, researchers at Glasgow claim the results of their study – recently published in Equine Veterinary Journal (EVJ) in partnership with the American Association of Equine Practitioners – look set set to turn what has always been regarded as a subjective process into a wholly objective one.
The study saw 17 healthy adult horses, all in work, fitted with sensors and trotted in a straight line. The sensors measured vertical pelvic movement asymmetry for both right and left hind limb strides and the average difference in maximum and minimum pelvic height between right and left hind limb strides.
A hind limb was randomly selected for 60 seconds of proximal flexion, after which the horse was trotted for a minimum of 10 strides. Response to the flexion was blindly assessed as negative or positive by an experienced observer.
John Marshall, lecturer in equine surgery at the University of Glasgow, who led the study, concluded: “A positive response to flexion resulted in significant changes to objective measurements of pelvic symmetry, supporting the use of inertial sensor systems to objectively assess response to flexion tests.”
Prof Jim Moore, North American editor of the EVJ, added: “The introduction of an objective approach to documenting lameness examination will not only help vets and trainers to investigate equine lameness more accurately. It will also serve as an unbiased method of communicating lameness examination findings among vets, trainers, farriers and other professionals.”
The next phase of research will be to establish cut-off values for objective assessment of other equine lameness diagnostic procedures, such as nerve blocks.