Stromsholm Clinic: Modern Farriery Techniques
Jonathan Nunn and Jay Tovey are both well known within the industry – regulars at farriery competitions and frequently ‘in the ribbons’ - and both have recently undertaken research as part of achieving the ‘gold standard’ in farriery, the Fellowship of the Worshipful Company of Farriers. Invited to present their findings at The Horse Trust’s Home of Rest for Horses by Carl Bettison AWCF, Managing Director of Stromsholm, the lectures delivered to the group of qualified farriers, apprentices and vets generated discussion and gave insight into the gain provided by scientific farriery research and its practical application.
Hoof Anatomy and Modern Farriery
Jonathan Nunn FWCF
Jon undertook the WCF Fellowship following an inspired period in which he transformed from a “clogger” (with no fuller!) to a regular participant in farriery competitions and successfully completed his Associate examination. His thirst for increased knowledge was realised. Jon’s presentation highlighted anatomy within the hoof and gave practical examples of his preferred methods for specific diagnoses.
Advancements in technology have led to the production of computer generated images and Jon regularly uses Hoof Explorer and Hoof Anatomy in addition to the Coach’s Eye app to not only assist him in his work but also as a method of recording and communicating with clients. Jon works regularly at the Pool House Equine Clinic where MRI images provide pinpoint diagnoses and uses this information in conjunction with his own static and dynamic assessments. The importance of quality x-rays was highlighted to provide the clear guidance needed to form a shoeing plan.
Jon provided an insight into the structures in the foot, highlighting medial and lateral ligaments and cartilage, some of which are incredibly difficult to locate upon dissection but play an important role. The use of wide branch shoes in collateral ligament damage was discussed, with many vets having a tendency to recommend the additional width being placed on the injured side. Jon feels that many of these horses have a rotation which he feels can worsen if shod with the increased weight on the injured side and advised being guarded with the application of such asymmetric shoes. More recently he has developed a personal preference for spider plates and “shoeing the whole of the foot”. The use of spider plates is advocated in instances such as navicular syndromes, for support or protection, fracture, frog injury, surface support, and collateral ligament injury.
Jon has experienced some success with heel graduation in cases of a negative P3 angle but highlighted the important of avoiding crushed heels and cited a preference for a heart bar with a leather pad. The use of a hind heart bar with full frog support is used where reverse rotation in the hind limb is apparent in horses with front limb lameness. ‘Restorative’ farriery is aimed at restoring the sole arch, increasing heel growth and increasing angulation whilst strengthening the hoof wall with alternative support to the frog and sole to share the load. Pads in this instance help to minimise bruising.
A further consideration is given to the use of the horse. The more specific the work, the more straightforward the shoeing is. Horses that cover multi-disciplines are more likely to cover more surfaces and surface interaction and traction, needs to be considered. Concave is not suitable on softer surfaces.
Examples of hoof trauma were provided in which the wound is unloaded by fabricating on site. Handmade shoes, readymade shoes and inserts are part of Jon’s tool box.
In all cases a continuation plan for shoeing and trimming and a continuation procedure is discussed with the client. The client needs to be committed to the procedures to be undertaken and to the likely cost. Jon keeps records for comparison; photos on his phone and/or written diary notes to ensure that each case can be recalled accurately and any progress is evaluated accordingly.
The digital cushion and its relationship with the external hoof
Jay Tovey FWCF
Inspired to be a ‘better farrier’, Jay undertook his research at the Royal Veterinary College following a number of clients purchasing thoroughbreds off the track with stereotypical “long toe, low heel” conformation. With regular requests to “trim the toe back and support the heels” and the application of rolled toes, side clips and shoes with bars provided inconsistent results his interest in this area was piqued. The focus on the palmar/plantar aspect of the foot led Jay to explore the digital cushion, its function and the ability to predict its depth using external parameters, specifically that of heel height.
The digital cushion is made of collagen, elastic fibres, fat and fibro cartilage and the amount of these materials vary between horses. It is situated proximal to the frog, has a poor vascular supply of its own, yet the digital cushion can account for a third of the palmar foot. It provides support to P3 and P2 and has a close relationship with the frog and collateral cartilages and does not work on its own. Its function has been said to absorb concussion and to also act as a ‘pump’ assisting the blood return system by working under compression/decompression. The three theories of energy dissipation include that of pressure, depression and hemodynamic flow were discussed.
Jay’s study took in 100 cadaver limbs which varied in breed and type and unshod and shod. Foot mapping was used as a repeatable method of trimming, loose sole was removed and the heels were trimmed to the widest part of the frog. CT scans providing a mid-sagittal slice were taken in additional to external measurements using digital callipers. The results showed a strong correlation in the depth of the digital cushion compared with heel height and a very significant correlation between the digital cushion and the external heel bulb depth.
The study by Bowker (2003) focusing on ‘good and bad footed horses’ was highlighted by Jay. In the study Bowker describes the composition of the digital cushion of different breeds and demonstrates that thoroughbreds and standardbreds have a softer digital cushion containing more fat and less fibrocartilage compared with heavier cob types. Fibro cartilage typically forms between 3 and 6 years. As thoroughbreds are shod at a younger age the digital cushion receives less stimulation indicating that horses left until later when they begin work may develop a stronger digital cushion.
Jay believes that “prevention is better than cure” and gives consideration to a period of time without shoes, however that is not always possible. The term ‘long toe, low heel’ he feels is misleading and describes vertical displacement of the digital cushion and crushed heels. The application of both straight and heart bar shoes was discussed to both share weight and support the digital cushion but noted that that these are not fully supportive, the compression/decompression of the foot is compromised, blood flow may be inhibited and thrush is likely. Jay uses softer, moveable packing material such as Magic Cushion or Matrix, combined with a frog support pad to pack the whole foot.
This valuable 3 hour clinic provided superb examples of recent practical research, and its application, by two highly regarded farriers. Warmly thanked by Carl Bettison, the appreciative attendees left not just with increased knowledge but confident that scientific research can be applied and is beneficial in every day farriery work. A very worthwhile and educational clinic.
Bowker, R. M. (2003) ‘Contrasting structural morphologies of ‘Good’ and ‘Bad’ footed horses.’ In: American Association of Equine Practitioners (Vol. 49, pp. 186-209).