Effects of farriery on locomotion

In the last decades, scientific studies proved beneficial effects of farrier interventions and shoe modifications. More refined measurement techniques have been introduced to measure the detailed pressure distribution underneath feet. These techniques have been used to analyse the equine gait especially the hoof loading and unloading patterns and have made it possible to gather scientific evidence of the effects and benefits of conventional farriery. As a result, developments in the production processes of mass produced horse shoes have been made. Today, most manufacturers have shoe models with a rolled toe in their range.

The effects of shoes are already quite well known such as improvement of animation of gait due to the added weight [1,2]. The latter is effectuated through changes in swing phase kinematics directly after shoeing [3] but is rather short term as horses get accustomed within a few days [2]. At impact shoes increase the vibrations that occur at hoof wall level [4,5]. At the level of the metacarpophalangeal joint so far no differences have been identified between shod and unshod conditions [5].

The initial contact with the ground is most often on the lateral part of the hoof [6–8]. This is more pronounced in the hind feet (98%) compared to the front feet (65%) in which the landing is shorter and shows more variability. It has been reported that at midstance, shoeing resulted only in changes in maximum component of the ground reaction force [5,9]. The limb load in the front was on average 118% of the body weight and 96% for the hindlimb [7,8,10]. At midstance the location of the centre of pressure (CoP) was closely around the centre of the shoe. During an 8 week shoeing interval the CoP at midstance had the tendency to shift in a palmar direction. From midstance to toe-off there was a distinct hoof-unrollment pattern; the CoP travelled towards a maximum lateral deviation and returned towards the dorso-palmar/plantar axis of the hoof. The effect of trimming was an intra-individual decrease in left/right difference in the hoof-unrollment pattern [6]. During the 8 weeks the hoof angle decreased about 3.3° and the dorsal hoofwall length increased by about 1.4 cm [11]. Horses compensated for changes in hoof conformation which developed during a shoeing interval [11]. As the capability to compensate was less in forelimbs the relative increase in loading of these limbs was larger [10,12].  […]