Shoes without Nails
Glue-on horseshoes are commonly used in the treatment of many equine foot disorders including orthopaedic disorders in foals and abnormal foot conformation. As the design and materials have evolved to produce stronger adhesives and a more malleable composition they are now a viable option for horses in high levels of work. Their success has been highlighted with notable wins by horses wearing glue-on shoes in a number of disciplines.
The variety of glue-on horse shoes commercially available is evolving quickly but broadly speaking there are three main types: synthetic glue-on shoes, aluminium core shoes and metal horse shoes.
Synthetic glue-on shoes are made from acrylic polymers, polyurethane or polyethylene. This type of shoe absorbs energy efficiently; it is lightweight and permits expansion of the hoof. Available in different sizes and, in some instances widths, the glue-on shoe is attached to the hoof with a resin with similar final hardness as the hoof horn. The foot is trimmed as normal and the frog is trimmed level with the wall-bearing surface to prevent contact between the frog and the horseshoe. The foot is cleaned and degreased with denatured alcohol (or similar such as surgical spirit) and placed on a clean floor (often covered in a towel). Resin is applied to the outside web of the shoe all the way round and the shoe is then placed gently onto the foot in the desired position until the resin has set – this can take up to a few minutes depending on the external temperature. The limb is then placed carefully on the ground for a further five minutes before allowing the horse to move.
Glue-on horse shoes with an aluminium core are made from an aluminium horseshoe (to provide rigidity) covered with polyurethane (to absorb shock) – the horseshoe may have ‘tabs’ which are used to glue the horseshoe to the hoof wall. The shoes can be shaped before application to the hoof as with a standard nail-on shoe (a shaping device is often provided by the manufacturer as the shoes cannot be heated). The foot is trimmed as normal and the surface of the hoof wall is lightly sanded and cleaned with denatured alcohol and placed on a clean floor. The inner surface of the ‘tabs’ are degreased with denatured alcohol and then the shoe is placed on the foot and the foot is allowed to bear weight on the ground. It is advisable an assistant holds the opposite leg off the ground at this stage to prevent the horse from moving the foot whilst the shoe is glued-on. Beginning at the heel ‘tabs’ a small amount of glue is placed behind each tab and allowed to run down between the tab and the hoof wall. The tab is pressed firmly against the hoof wall and held in place for a few seconds. This is repeated until all the tabs are securely fixed to the hoof wall.
Metal horseshoes may be glued-on to horses with a very broken hoof wall potentially allowing the horse to stay in work whilst the new hoof grows. As before the foot is trimmed and degreased with denatured alcohol and placed on a clean floor. A horseshoe ‘liner’ made from neoprene strips is fitted onto the inner web of the shoe to prevent resin passing to the solar area of the foot and causing bruising of the sole. Resin is applied to the outer web of the horseshoe and the shoe is applied following the same procedures as for synthetic glue-on shoes. Some manufacturers advise ‘wrapping’ the foot whilst the resin sets completely and this wrap can be removed later. A further alternative is a glue-on shoe incorporating an adhesive bonded fabric cuff which promises to be stronger than a nail attachment and possess an effective shock absorbing rim pad.
The success of glue-on horseshoes is largely dependent on the correct application in suitable conditions carried out by a suitably qualified and competent farrier. The shoeing area must be clean, dry and, in many cases, well ventilated. The procedure is best carried out wearing latex or rubber gloves and with some products a mask is also recommended. Many manufacturers of glue-on shoes conduct training days for farriers to ensure the products are fitted correctly and the maximum benefits are realised.
Glue-on shoes are not always suited to changing environmental conditions, for example from muddy field to dry stable and across varying terrains, and cleanliness and hygiene is paramount to the success of the shoe both in longevity of attachment and to avoid infections such as thrush due to the decreased exposure to air. Increased application time compared with nailing-on shoes can cause some horses to become restless and need sedation. Higher material costs plus additional tools required and increased application time also means that glue-on shoes are far more expensive than traditional shoes. Many consider glue-on shoes to be aesthetically less attractive.
However, applied correctly a glue-on horseshoe can last as long as nail-on shoes and, in some cases, longer if nailed-on shoes have been thrown or have become loose early in the shoeing cycle. They are hard-wearing and good for sensitive footed and ‘hammer-shy’ horses. In remedial and therapeutic applications the benefits of glue-on shoes have revolutionised treatment and success rates, particularly in cases of laminitis and angular limb deformities in foals. Glue-on shoes are non traumatic and non invasive.
As with all areas of science new products are continually being research and trialled. One such product is a horseshoe shaped mould which is fitted onto the horse’s foot into which urethane is injected. Once set, the mould is removed leaving a ‘shoe’ forming an extension to the horse’s hoof which provides both protection and traction. For many the application of glue-on horseshoes will be a temporary solution to a hoof problem and it is unlikely that glue-on shoes will replace traditional steel and aluminium in the future however with the product shelf constantly evolving glue-on shoes may become a regular feature in leisure and competition horses.
