b'Surface Semantics indicate whether the ground deforms and We cant really move forward withto what degree, Crevier-Denoix says. understanding the effects of footing onHard surfaces, including dry dirt and horses biomechanics and health until wepavement, are associated with lower limb can first agree on how were describinglesions, including in the pastern, fetlock, the footing, says Lars Roepstorff, DVM,and coffin joints, in clinical cases, says PhD, professor of equine functionalJean-Marie Denoix, DVM, PhD, director anatomy at the Swedish University ofof ENVAs Centre dImagerie et de Re-Agricultural Sciences, in Uppsala.cherche sur les Affections Locomotrices So, one scientific objective is sim- Equines. If these surfaces are irregular ply getting people to speak the sameand hard (e.g., frozen pastures in winter), language when theyre characterizingresulting in uneven foot placement and surfaces, he says. torque on the lower leg bones, the injuries While Crevier-Denoixs shoe is anare worse.invaluable tool in understanding how aCrevier-Denoixs research also reveals horse reacts to a surface, its not one thatobvious correlations between hard sur-can be used as a global standard becausefaces and superficial digital flexor tendon it would require using the same horse,(SDFT) injury risk, she says. She found Roepstorff says. A machine developed bythat Standardbreds trained on hard sand Mick Peterson, MS, PhD, executive direc- were far more likely to have early signs tor of the Racing Surfaces Testing Labora- of SDFT and fetlock damage visible dur-tory and professor of biosystems anding image-based screening within four agricultural engineering at the Universitymonths than those training on soft sand of Kentucky, in Lexington, on the other(TheHorse.com/158926). hand, drops weight into surfaces to mimicMeanwhile, in horses jumping on the loads and speed of a moving horse.a sand-fiber-mix footing, she noted While the method doesnt use an equineincreased impact shock and vertical limb, it applies the same force and move- loading rate on limbsincreasing injury ment to the footing every time to allow forriskwhen the softer top layer was only 7 standardized verifications, he says.cm thick compared to a cushier 13 or 20 The goal is to provide riders with com- cm. If you try to cut costs with a thinner prehensible and comparable descriptionstop layer, youre just going to end up with of surfaces, says Roepstorff. Its not tomore lameness, she says.say if the surface is good or bad but toHard surfaces are even more problem-rate various aspects on a scale so peopleatic with repetitive training, long rides can learn to associate that rating withover extended distances, and/or frequent what they feel, he says. But that has tocircling, says Denoix. Riding club horses start with a more universal language. experience more trauma to the lower joints when theyre constantly turning in circles in hard-surface arenas, he says. Theres not even aEndurance horses face similar risks be-consensus yet on whatcause of distance traveled. Theyre cover-ing 100 kilometers (62 miles) or more, so soft and hard mean. if the ground is hard, this isnt going to DR. NATHALIE CREVIER-DENOIX be ideal for their joints, and (they) could even develop road founder, a form of laminitis, he says. That language includes terms suchHowever, the occasional cross-country as cushion, firmness, grip, responsive- run on firm ground is less likely to be a ness, and consistency. Currently, though,risk factor for joint injury because the theres not even a consensus yet on whatdistance is shorter and the number of soft and hard mean, Crevier-Denoixjumps doesnt compare to the repetition says. Objective measurement should help,of strides experienced in disciplines such she adds, but if its going to provide reli- as endurance, he adds. able information about injury risks, theRisks can multiply due to the nature of tool needs to reproduce the movementa hard surface, says Crevier-Denoix. Firm and timing of a horse foot. footing provides better push-off, making horses move faster. This creates a double The Sweet Spotpenalty because higher speeds are, them-Although not officially defined, theselves, a risk factor for injury, she says. terms hard and soft footing basicallyRiders need not avoid hard surfaces TheHorse.com|The HorseMay 202033'