A team of researchers at Michigan State University’s (MSU) McPhail Equine Performance Center offers hope to horse owners facing underrun heel and flat-footed woes with a 16-month study examining the short-term and long-term effects of a specific barefoot trimming technique on hoof conformation.

In the study, seven previously barefoot horses were trimmed every six weeks with a technique that leveled the hoof to the live sole, lowered the heels, beveled the toe, and rounded the peripheral wall. The sole, frog, and bars were left intact.

"This study has shown that a group of school horses performed well and remained sound when trimmed so that the frog, bars, and sole of the foot were engaged in the weight-bearing function," explained Hilary Clayton, BVMS, PhD, Dipl. ACVSMR, MRCVS, the Mary Anne McPhail Dressage Chair in Equine Sports Medicine at MSU. "We believe it is important for these parts of the foot to contact the ground, not only to distribute the weight-bearing forces and to support the coffin bone from below, but also to provide the horse with proprioceptive input from receptor cells in the heels."

The first four months of the study established the hoof shape representative of the barefoot trim. From this baseline, morphological (shape and structure) changes in the hoof’s response to the trim technique were monitored from months 4 through 16. At 0, 4, and 16 months, the researchers measured hoof morphology from lateral (from the side), dorsal (from the rear), and solar photographs, as well as lateromedial (side to side) radiographs.

As the study progressed, subjects showed palmar/plantar migration of th