ARCHIVE - ARTICLES 2010

April 10 - Quantitative horse hoof trimming protocol for research purposes

April 10 - Accreditation of the American Farriers Association qualification Certified Journeyman Farrier

April 10 - Rasps, fish hooks and The Battle of Trafalgar

 

Archive - Forge Magazine - April 2010
Quantitative horse hoof trimming protocol for research purposes

M. N. Caldwell. FWCF, J. D. Reilly, BSc (Hons), BVSc, PhD, MRCVS. & M. Savoldi2 CJF.
The Farriery Department, Myerscough College, Myerscough Hall, Billsborrow, Preston, Lancashire PR3 0RY . 2 9350 Canyon Road, Sheldon, 93175 CA

Background
Many approaches to gathering data on the shape of the equine hoof refer to a trimming protocol without specifying the full farriery details that have contributed to it. In the past this may have sufficed for a veterinary-based approach to a particular subject, but a rigorous farriery appraisal requires detailed information about the reference points used for a repeatable hoof trim for research standardisation purposes.
Aim
This paper aims to give detailed information about the farriery reference points that can be used to give a repeatable farriery hoof trimming protocol. This we call the geometric proportions (GP) trimming protocol. This can then be used for research purposes as a means of controlling important variables, which will then allow reliable and farriery controlled quantitative data to be collected.
Introduction
Farriery has relied on the transfer of knowledge, custom and practise from one generation to another. Foot balance is a quintessential aspect of farriery; what proportions of the hoof capsule constitute normal or even what is desirable have tested farriers and veterinary surgeons for generations.
Turner (1988) advocates a series of measurements to assess foot balance, yet these comparisons were made against the proportions of an anecdotal standardised model (Butler 1985) based largely on the work of Russell (1897). Russell argued that symmetry around the central axis was the perfect form for levelling and balancing the foot. Russell further argued that ‘the height of wall from coronary band to ground bearing border should be the same at any two opposite points’. To this day this symmetry remains the basis of standard farriery texts (Hickman 1987; Stashak 1990; Butler 1985) and corrective manipulation.
Turner (1986a; 1986b and 1988) and others (Stashak 1990) have attempted to define a number of hoof abnormalities but none of these authors describe any degree of biomechanical variance from the standard text model or allude to a trimming protocol from which abnormalities could be assessed objectively.
Debate amongst hoof-care professionals rages to this day, with poor hoof balance often cited as a major causative factor in these types equine foot and lower limb pathologies (Eliashar et al 2004). Many veterinarians and Farriers assert that a large proportion of the lameness seen today, could be prevented or treated through better farriery (Kane et al 1998, O’Grady and Poupard, 2001).
While there are many theories on this subject there seems to be no definitive protocols for farriers to follow. Ovnicek (1997) advocates the natural balance trim based on the interpretation of foot condition in feral horses. Duckett (1990) suggests trimming the feet to the centre of articulation of the distal interphalangeal joint (DIP) using a trimming plan that coordinates external reference points around the hoof capsule. Duckett theorised that the location of these external reference points of the hoof give an indication as to the location of specific internal anatomical and biomechanical land marks around which the foot should be trimmed and or shod.
Savoldi (2006) utilises the uniformity of sole thickness (UST) method and links hoof form to the orientation and function of the internal structures. He asserts that the form of the external hoof is directly related to the form and function of the internal structures. UST has been used to quantify orientation of internal structures in cadaver feet in saggital and frontal planes (Craig 2005; Savoldi 2006).
The conclusions of recent studies on the dynamic effects of foot trimming on the stance phase (Balch et al 1997; Van Heel. 2004, 2006a) including point of force loading and trajectory may have also been influenced by their trimming protocol and biomechanical variation within their study group. However, they failed to quantify the exact trimming protocol used merely citing the restoration of correct Hoof Pastern Axis (parallel dorsal hoof wall - phalangeal alignment angles) as their preferred method of achieving foot balance. Given the complexity of the biomechanical interactions of the foot and its internal anatomical structures while under load it is difficult to see how their results can be interpreted into everyday farriery protocols. Anecdotal farriery evidence of corrective farriery results suggests a more holistic assessment is required to achieve equilibrium of loads and thus translate static balance into dynamic balance.
The GP trimming protocol is aimed at restoring static foot balance and is based on trimming the foot with particular reference to external reference points on the hoof capsule. The major reference points along the longitudinal axis of the frog are thought to relate to internal anatomical or physiological structures at fixed points within the foot. The protocol is based on quantifiable elements of the previously described trimming methodologies (Duckett 1990; Ovnicek 2003 & Savoldi 2006).
The protocol allows for:
• accurate assessment of the requirements for farriery
• any interventions necessary in the amelioration of foot pathologies and
• correction of gait abnormalities when used in conjunction with diagnostic imagery.
The aim of the GP trimming protocol is to maintain a healthy functional hoof capsule without compromising the integral strength of the dorsal hoof wall (DHW) by preventing migration of the wall from the solar junction (flaring) associated with excessive tension and compressive forces experienced under conditions of abnormal loading.

TRIMMING PROTOCOL
Initial assessment
The limb is assessed for conformational deviation and hoof capsule orientation using lateromedial, dorsopalmar / plantar, solar and longitudinal axial eye line projections (Fig 1). Particular reference is made to hoof proportions at easily identifiable anatomical land marks on individual projections of the hoof and their geometric relationship with each other (Turner 1988) in order to build a three-dimensional image of the finished proportions of the trimmed foot. Hoof wall phalangeal alignment, heel toe ratio and the height of wall from coronary band to ground bearing border should be the same at any two opposite points (Butler 2005) are the basis against which initial assessment is compared and from which post trim interventions and shoe modifications can be calculated.
Frog, sole and white line
The trim relies heavily on the initial assessment and identification of anatomical landmarks and proportions. It is essential that the co-lateral sulci are clearly visible to their full depth, and that the true apex of the frog is identified.
The frog and perioplic horn binding in the heel buttresses are exfoliated to expose the collateral sulci to their full depth and to accurately assess the true position of the point of frog (where the frog horn blends into the solar horn).
The exfoliating sole is removed to live sole including the sole callus found at the toe area between 10 and 2 o’clock. The white line is then exfoliated to reveal the sole and horny wall interface (Ovnicek 2003; Savoldi 2006) (Fig 2).
1. Exfoliate the area from seat of corn to the true point of frog medially and laterally.
2. Continue removing exfoliating sole to live sole depth (identifiable as waxy horn at the sole white line interface at the sole's leading edge) (Fig 2). Revealing the true position of the sole white line interface, will determine the amount of excess dorsal hoof wall that can be safely removed from the solar surface and the dorsal area by way of flare dressing (Fig 4a).
3. Trim damaged structures back to viable tissue, cleaning any questionable areas.
4. Identify the sole’s leading edge with the white line interface by carefully removing the exfoliating horn at the sole leading edge from quarter to quarter, with the knife in an upright position (Fig 3). The white line area is then exfoliated exposing the true interface allowing the live sole (Fig 2).
5. Carefully remove the rest of the exfoliating solar horn; this reveals the true solar plane
(Fig 2).
The bars are trimmed to normal proportions, removing damaged or weak horn, to confluent bar tissue (Figs 2 & 4a). The frog is trimmed back to live frog in proportion to the foot with ground pressure to be engaged when the foot is static (Fig 2).
Bearing border
The excess wall at the bearing border is removed to a horizontal plane (Figs 5 & 6) with the live sole; this determines the vertical height of the dorsal hoof wall (DHW) (Duckett 1990).
Note: Before trimming the bearing border reassess the solar plane with the long axis of the limb. It is not always practical to trim the bearing border perpendicular to the longitudinal axis of the limb. In cases with even mild angular limb deformity (ALD), the bearing border is trimmed horizontal to the solar plane (Fig 6) taking into account any wall flaring or hoof compression.
1. Excess hoof wall is removed parallel to the live sole (the author prefers to trim toe to heel, others may trim commencing at the heel), great care is taken not to trim down so far as to invade the live sole (Figs 2 & 4a)
2. The heels are trimmed approximately to the widest part of the trimmed frog or the palmar / plantar aspect of the exfoliated central sulci
(Fig 4a & 6).
Note: Before applying the final rasping, orientation of the bearing border to both the longitudinal axis of the limb and the solar plane are re-assessed.
3. Rasp the hoof with even pressure over the rasp, being careful not to rasp down below the live sole, or lowering the bearing border below the sole.
Note: Trimming the bearing border and dorsal wall in this way is thought to lead to an overall approximate heel to toe height ratio of 3:1 being maintained (Fig 7).
Hoof wall shape and thickness
To determine the optimum dorsal distal position for the dorsal hoof wall we identify an external reference point on the bearing border, positioned 9.5 mm (in the average sized riding horse) palmar to the true apex of the frog (this point is often referred to as Duckett’s Dot (Duckett 1990) and represents the centre of pressure (COP) at mid stance). The distance from COP to the outer edge of the medial wall should correspond to the distance from COP to the dorsal distal tip of the dorsal hoof wall (Fig 4b). ‘Flare dressing’ the dorsal hoof wall in line with this measurement determines P3 orientation with the dorsal hoof wall without compromising the dorsal hoof wall’s structural integrity (Fig 7).
Two imaginary lines are projected dorsally from the heel buttresses parallel to the longitudinal axis of the frog to intersect the white line sole interface (the location of what has become known as the pillars (Duckett 1990)) (Fig 8).
1. From the farrier position, the toe is reduced in thickness and shaped at the distal dorsal hoof wall symmetrically.
2. The medial and lateral hoof walls are reduced in thickness from toe pillar to quarter (widest point of the foot) leaving an equal thickness of dorsal hoof wall (DHW) from quarter to quarter (Fig 8).
Note: Dorsal hoof wall thickness is determined by the width of the wall and the inner border of the white line interface at the quarters.
3. The hoof is then brought forward and the dorsal hoof wall flare dressed, going no more than approx. 25mm – 50mm dorsoproximal so as not to compromise the hoof capsule’s integral strength (Fig 7).
Note: The dorsal hoof wall is only flair dressed where there are deviations in symmetry to correspond to the phalangeal axis. This leaves an equal amount of wall from the white line / solar interface around the DHW circumference.
Dorsopalmar proportions are verified by comparison of physical toe length measurements taken with engineers calliper / dividers to measurements from the dorsodistal tip of the dorsal hoof wall to key external anatomical land marks along the bearing border.
1. The linear length of the toe should then correspond to the distance from the dorsodistal border of the toe to the widest point of the foot (Fig 9). This is said to represent the centre of rotation (COR) of the distal interphalangeal joint (Duckett 1990; Caldwell 2001).
2. This measurement should also correspond to the distance from the position referred to as Duckett’s Dot or COP to the widest point of the frog at its juncture with the heel bulbs (Fig 9) (Chapman 1984; Duckett 1990).
Note: Anatomically we visualise the centre of pressure (COP) as being located between the insertion of the deep digital flexor tendon (DDFT) at the semi lunar crest and the insertion of the common digital extensor tendon (CDET) at its insertion around the extensor process of the distal phalanx (Duckett 1990,
Wilson et al 1998).
The foot is said to be proportionate if all three distances are of a similar value± 6mm (D'Arcy et al 2008; Jones et al 2008 and Conroy and Caldwell 2008).
Conclusion
The technique of trimming the bearing border to the solar plane orientates the hoof capsule in line with skeletal deviations, and thus gives a more accurate medial / lateral and proximal / distal orientation, and leaves a uniform sole thickness around the white line / solar interface (Savoldi 2006) in addition to quantifiable dorso palmar proportions (Duckett 1990). This technique allows for more accurate radiographic measurements (Kummer et al 2004; 2007; Caldwell et al 2009).

 

Archive - Forge Magazine - April 2010
Accreditation of the American Farriers Association qualification Certified Journeyman Farrier

By Stephen Newman

The American Farriers Association (AFA) has been running the Certified Journeyman Farrier (CJF) exam since 1971, and this has been recognised by the Farriers Registration Council (FRC) since 1994 as being the equivalent standard to the Worshipful Company of Farriers (WCF) Diploma examination. In order to ensure standards remain comparable, members of the FRC Visitation Panel assess the CJF examination every three to four years. The last visit was to Florida in 2008. The AFA is proud to have this association with the UK.
The CJF exam, which I had the privilege to oversee, was sponsored by the Florida State Farriers Association (FSFA) held at Bryce Burnett’s farriery shop in Zolfo Springs, Florida, over a two-day period. The then President of the AFA
Mr Andrew Elsbree CJF was present throughout the exams and was a vital source of information.
Exams are held throughout the USA, with some 45 exams being held in 2007. Currently, there are approximately 70,000 full- and part-time farriers in the USA; approximately 2670 of these are members of the AFA of which just under 1000 are CJF. All candidates require at least two years’ shoeing experience and must have successfully completed the Certified Farrier (CF) exam. There is no time limit between taking the CF followed by the CJF exams (both can be taken in the same week) and they can be taken as many times as the candidate wants, but only once at each individual examination sitting, at a cost of $45 per time.
The AFA has set criteria for becoming an examiner and tester. All examiners belong to the AFA, whereas the testers are under their individual association, in this case the FSFA. To become a tester, a candidate must be a CJF who has been recommended by their association. They are then required to examine/test at three exams and or attend three seminars. The examiners are testers who have been recommended by their association to the AFA; once recommended they are required to undertake three provisional exams.
Candidates can take all of the CJF exam or part of it in one sitting, but all sections must be successfully completed within two years. In cases where the candidate does not achieve this, then they must sit the entire exam again.
The examination
All candidates sit a written paper. Following the format of previous years, a ‘tick-box’ style paper totalling 80 questions seemed to cover the entire syllabus in detail, with a pass mark set at 80 per cent. The AFA has four different CJF written examinations. Where a candidate has failed part of the examination they may retake that part at the next organised exam. Candidates with learning difficulties are allowed to have a reader/writer. Currently the AFA is developing question papers in French and Spanish.
The candidates that were taking the live horse shoeing discussed their shoeing plan with the examiner and a shoe fit agreed from the AFA set criteria of A, B or C (length of heel fit). The test consisted of shoeing a horse all-round with handmade plain stamped shoes from the candidates’ vans. If a candidate did not reach the required marks in any of the phases, or scored less than a three out of 10 marks in any of the sections (for example, sole trim), the candidate was stopped. The candidate was then briefed on their errors by the examiner.
The AFA has published a helpful study guide (Certification Study Guide, revised 2008), which can be found on its website,
www.americanfarriers.org

 

Captions from top to bottom, left to right:

The President of the AFA briefing the candidates on the exams, they where then shown the standard required for the day

One candidate's finished job, not forgetting they have shod all four feet in the same time that we shoe two in the Diploma exam

A plainstamped shoe made by Bryce Burnett to show the standard required

One of the horses used for the exams had been bitten by an alligator two weeks before the exams! And we moan about flies and midges!

Bryce Burnett forge where the exams took place

After the exams had finished I had a day before my flights. Bryce Burnett invited me to go alligator hunting at night with a rifle and bow and arrow!!
Having seen the horse that was bitten I decided to go diving on a couple of wrecks in the Gulf of Mexico some 12 miles out to sea, much safer!!

 

Archive - Forge Magazine - April 2010
Rasps, fish hooks and The Battle of Trafalgar

By Jeffrey Newnham DWCF

UK farriers spend approximately £1.5m per year on rasps. After speaking in depth with farriers over a two-year period, anecdotal evidence revealed that in every box of six rasps used for trimming, two were poor quality and rarely lasted more than a couple of days, two were ‘okay’ and lasted up to a week, and two lasted more than a week before being used for ‘clenching up’. These figures did not vary significantly between manufacturers or models. In some cases, complete consignments of rasps were returned to suppliers. With £1m spent annually on rasps that were at best good and at worst OK, and £.5m on rasps that did not work, I looked at ways of lengthening the useful life of rasps that could dramatically reduce waste/replacement.
After using a buffing mop and various abrasive products to mechanically sharpen my rasps for many years, my attention was drawn to whether a method of chemically sharpening (as used for products such as fish hooks) could be used for rasps. My research took me to the work done by Tumminaro in 1995. Following a year of my own testing using an etching and sharpening solution, manufactured by Chemsharp Inc on 30 used and discarded rasps, I found that chemically sharpening and/or etching a sharp edge were not only simple and effective but the ‘pickling’ process was easily performed with a suitable dip tank and a good quality solution. Chemical sharpening was, I discovered, a simple, effective treatment system that took up little space.
The only down side seemed to be the reliability of production and distribution. By teaming up with a UK chemical company and, after testing on hundreds of rasps, a new ‘pickling solution’ was developed. The main focus on developing a new liquid was to take into account the arena in which the liquid would be used. The liquid had to:
❙ Be as safe and stable as possible;
❙ Be able to be used by untrained operators;
❙ Conform to new detergent regulations;
❙ Comply with REACH (Registration, Evaluation, Authorisation and restriction of Chemicals);
❙ Overcome the frothing reaction (when rasps are immersed in a pickling solution, the reaction was to lift debris from the rasp; this debris rose to the top of the liquid in a ‘foam’ where it either stayed or overflowed the dip tank. When the rasps were removed from the dip tank much of this contaminant was deposited as the rasps were removed, thus coating them with a sticky residue that needed to be removed by washing/scrubbing);
❙ Flexible, the ‘pickling’ process should not be time critical;
❙ Remain ‘still’ (no frothing or foaming, so that the etched debris would fall to the bottom of the tank), and
❙ Efficient
Testing
The primary method for testing the liquids we developed was simple; ‘lets stick a rasp in it and see what happens’! This progressed to, ‘lets try this rasp on a foot’. Not very scientific I agree, but it gave us the feedback that we needed to progress. After a year of ‘sticking a variety of rasps in various solutions’ and then testing them on their effectiveness for trimming and clenching up (bearing in mind that these were already rasps that had been discarded as useless, the results were very encouraging. Making this liquid available to farriers has provided essential feedback for further product improvement.
We then reached a point were anecdotal evidence and simply saying ‘this is great’, was insufficient to help other farriers reduce the number of new rasps they were buying and show them that rasps, far from being a disposable hand tool, could easily be sharpened and re-used.
We then looked at ways we could test the restorative qualities of our liquid, and called on the services of the Cutlery and Allied Trades Research Association (CATRA), which has been carrying out this type of testing since 1952.
The tests we asked CATRA to perform for us had the following parameters:
We would test three out of a possible 20 different rasps (one economy rasp, one mid-price rasp and one top of the range rasp)
We would not examine any rasp prior to testing
We would test both sides of the rasps
Test equipment used included a CATRA rasp machine, CATRA software and CATRA measuring devices, and a mild steel block.
The tests
Test 1. Treat a new, unused rasp with EasySharp Liquid
We took one of each of the rasps, soaked them for four hours in the EasySharp Liquid, removed and dried them.
1. Using the CATRA flat file test machine, take a 100 cut light load test and measure the metal removed.
2. Take a 200 cut heavy load test and measure the metal removed.
3. Repeat the light load test and measure the metal removed.
4. Repeat steps 1 to 3 on the other side of the rasps.
Test 2. Test untreated new rasps
Using the other three rasps
1. Using the CATRA flat file test machine, take a 100 cut light load test and measure the metal removed.
2. Take a 200 cut heavy load test, and measure the metal removed.
3. Repeat the light load test and measure the metal removed.
4. Repeat steps 1 to 3 on the other side of the rasp.
Test 3. (a) Test rasps used in Test 2 that had been treated with EasySharp Liquid and (b) test same rasps after they had been used
1. Subject the rasps to EasySharp treatment.
2. Using the CATRA flat file test machine, take a 100 cut light load test and measure the metal removed.
3. Take a 200 cut heavy load test and measure the metal removed.
4. Repeat the light load test and measure the metal removed.
5. Repeat steps 2 to 4 on the other side of the rasp.
6. Repeat steps 1 to 5.

PART 2 of this article, which will include ‘Results’ and ‘Recommendations/Conclusions’ will be published in the next edition of Forge Magazine,
if you can’t wait until then, they are viewable on www.easysharp.co.uk ( follow link to test results )
Ps. If you are wondering “What the heck has this to do with The Battle Of Trafalgar”…….Easy Sharp Liquid is UN1805!

Further information
www.easysharp.co.uk
www.hse.gov.uk/coshh/index.htm
http://www.easysharp.co.uk/Video.html
http://www.hse.gov.uk/chip/phrases.htm
www.catra.org
www.boggstool.com/liquidhone.htm
http://www.fishingpatents.com/chemically-sharpened-hook-patents-usa.shtml
http://www.artemischem.co.uk/