A Comparative Study Between the Dynamic Analysis of Aluminium and Steel Shoes on Show Horses.

Transcription

1 MR 3127 BSc (Hons) Farriery Double Dissertation. A Comparative Study Between the Dynamic Analysis of Aluminium and Steel Shoes on Show Horses. Mark Wood Dip WCF, FdSc. Student number: Word count: Mark Wood Dip WCF, FdSc. April 2013! Page 1

2 Acknowledgements I would like to give me sincerest thanks to Mrs Lorraine Allan MRCVS for her patience and support over the past two years when I needed some guidance completing my dissertation. I would also like to thank Mark Caldwell FWCF for all his help and support during my time spend in higher education. Mark Rosbotham has also proved to be very invaluable for helping me to understand and teach me how to calculate my statistical data. Lastly and by no means least I would like to thank all my peers that have been on this journey with me, for their support and reassurance, when I have had to get through tough times and keep going when all seemed lost and insignificant, it has been worth the struggle and I have made some life long friends, thank you! Mark Wood Dip WCF, FdSc. April 2013! Page 2

3 Abstract Introduction It is a commonly held belief amongst owners of show horses that a lighter aluminium shoe will give a more preferential stride action on the show horse compared to a more traditional steel shoe. All the show horses in this study were selected due to their soundness, conformation, temperament and good quality hoof capsules. Study design This is a pilot study of ten horses which is quantitive and experimental. Materials and methods 10 clinically sound show horses, 3 mares and 7 geldings aged 7 to 16 years and weighing 490kg to 706kg were used in this study. To reduce the variables and increase the validity of this study all the horses were trimmed by the researcher, who ensured that the trimmed heel terminated near to the widest part of the horny frog. Each horse was shod with both aluminium and steel shoes, after a marker was attached to the hoof they were trotted in a straight line, 4 times in each type if shoe by a confident handler for video recording. One stride from each trot up video was taken and analysed with a gait analysis program. The average weight of the aluminium shoes was one third the weight of the steel shoes used in this study. Results The hypothesis for this study was that a lighter aluminium shoe would provide the show horse with a more preferential stride action than a more traditional steel shoe. A two way ANOVA test was used on the data giving a probability value of P=<0.001 showing a significant difference between the two types of horse shoes. The overall result was that we can accept the hypothesis that there is a difference with a P value of p = <0.001 and F 3,8 = Conclusion The weight of a horse shoe does seem to alter the stride length of show horses, but it could be to the soft nature of the aluminium shoe is detrimental to the soundness and longevity of the horse s showing career. Mark Wood Dip WCF, FdSc. April 2013! Page 3

4 Contents. Title page Page 1 Acknowledgments Page 2 Abstract Page 3 Table of contents Page 4 Chapter 1 Introduction and Rationale 1.1 Rationale Page The importance of horse shoes Page Different types of horse shoes Page Gait analysis Page 9 Chapter 2 Literature review 2.1 Introduction Page Marker placement Page Camera methods Page The use of force plates and treadmills Page The most appropriate gait and speed for gait Analysis Page Different horse shoe material Page Stride length Page Flight patterns Page Hoof trimming protocol Page Shoe weights Page Statistical analysis Page 21 Mark Wood Dip WCF, FdSc. April 2013! Page 4

5 Chapter 3 Methodology 3.1 Study aims and objectives Page Hypothesis Page Introduction to methodology Page Reliability and validity Page Sample size and inclusion criteria Page Materials and methods Page Hoof trimming protocol Page Standardisation Page Data analysis Page Ethical considerations Page 28 Chapter 4 Results 4.1 Group selection Page Group details Page Shoe weights Page Stride lengths Page Descriptive statistics Page 32 Chapter 5 Discussion 5.1 Standardisation Page Limitations Page Results Page Differences between aluminium and steel shoes Page 37 Chapter 6 Conclusion and recommendations 6.1 Conclusion Page Recommendations for future research Page 38 Mark Wood Dip WCF, FdSc. April 2013! Page 5

6 References Page 39 Figures 4.1 Details of case studies page Chart showing the weight comparison of aluminium and steel shoes page Table for length of stride of each trot up, measured in centimetres page Descriptive data of each case Page Frequency of stride length for both types of shoes Page Two-way ANOVA: Length (cm) versus Shoe Page Stride length chart from Minitab 16 Page Interval plot graph Page Effects plot for length of stride for shoe, case and each of the three trot ups Page 35 Appendices Appendix 1. Marker placement Page 45 Appendix 2. Camera placement and calibration Page 46 Appendix 3. Client letter Page 47 Appendix 4. Raw data of case studies Page 48 Appendix 5. Corn caused by aluminium shoes Page 48 Appendix 6. Hoof marker placement, with aluminium shoe Page 49 Appendix 7. Aluminium shoe with groove Page 49 Mark Wood Dip WCF, FdSc. April 2013! Page 6

7 Chapter 1. Introduction Rationale. It is a commonly held belief amongst owners of show horses that a lighter aluminium shoe will give a more preferential stride action on the show horse compared to a more traditional steel shoe. Show horses in the United Kingdom (UK) are assessed for temperament, conformation and most importantly movement. These horses will be judged on all aspects of their conformation, in lay terms what a horse looks like or how it is put together. It consists of two aspects, the skeleton and muscular development (Pilliner and Davies 1996). Anecdotal observations by the researcher has highlighted various problems associated with the use of aluminium shoes on the larger show horses, including hoof capsule distortions, due to the soft nature of the aluminium and the lack of support it gives as a shoe. This has also been observed by Williams and Deacon (2001) and is described in more detail later in this dissertation. A large percentage of these horses start to develop problems pertaining to the horny hoof capsule including widening and splaying of the fore feet, flattening of the sole due to the horny wall spreading and collapsing of the heels. This in turn can lead to mechanical laminitis, solar bruising, corns (Appendix 5) and excess pressure placed upon the deep digital flexor tendon, distal sesamoid bone and surrounding soft structures which can impact on the soundness of the horse The importance of horse shoes. Since domestication of the horse, the need to prevent wear by the application of shoes was closely followed by the need to prevent slippage. Numerous solutions were described in farriery and veterinary literature to help the working horse obtain purchase and a secure footing (Dollar and Weatley 1898). The most important part of a horse is it s four hooves, the hoof capsule is a hard outer layer of horn which surrounds the sensitive structures and bones within it. In the wild, horses' hooves are worn down as fast as they grow and are always the correct length (Humphrey 1995). Farriery is the art of shoeing horses, it is necessary Mark Wood Dip WCF, FdSc. April 2013! Page 7

8 to enable horses to work under their domesticated circumstances (Colles and Ware 2010). Horse shoes are primarily attached to the hoof of the horse to protect the sensitive structure within the hoof capsule. Horses which work regularly on the roads without shoes, would wear their hooves more quickly, then will become sore and lame (Humphrey 1995). Hickman and Humphrey (1998) supported this and stated that as soon as man used horses to carry loads and pull vehicles, the hooves wore away more quickly than they were renewed, exposing the sensitive structures and resulting in pain and lameness, which prevents the horse performing the job for which it was intended, usually costing the owner money and time to rectify. Modern horses tend to have relatively larger bodies and smaller feet, this is why they can become easily bruised on uneven ground, a shoe protects the foot from bruising as well as excessive wear (Humphrey 1995). The horse shoe also gives extra grip and will help to support the hoof in weak footed equines. Hooves are continually growing and shod or unshod, they need the attention of a qualified farrier on a regular basis to keep the hooves in the best shape and condition as possible (Humphrey 1995). Roepstorff et al (1999) suggested that horse shoes were originally intended to protect the hoof from wear. The growth rate of the hoof wall is approximately 7mm every 28 days, at this rate it would take between 9 and 12 months for the hoof capsule to renew itself (Pollitt 1990 and Josseck et al 1995). Currently different farriery techniques are employed to improve performance and prevent injury with the use of different pads and shoes. Balch et al (1997) stated that ideally, shoes properly fitted to horses hooves, should serve as extensions to the hoof and would have the following characteristics: perpetuate the normal anticoncussion mechanisms of the hoof, position the ground bearing surface of the hoof in the correct spatial relationship to the axes of the upper limb and cannon bone, prevent excessive wear of the epidermal hoof, prevent excessive trauma to the dermal hoof, they should also offer traction characteristics of the hoof in a manner appropriate for the horse's athletic ability. Mark Wood Dip WCF, FdSc. April 2013! Page 8

9 1.3. Different types of horse shoes. A horse shoe is simply a bar of steel which has been bent to the shape of the distal border of the hoof and nailed to it (Humphrey 1995). Horse shoes are traditionally made from mild steel due to the cheaper cost and being harder wearing. Aluminium is also used, which is more expensive but weighs considerably less and wears more quickly due to its softer structure. The aluminium does not provide the same amount of support as a steel shoe due to the soft nature of the metal (Williams and Deacon 2001). Plastics and rubber have also been used but also are more expensive and time consuming to apply. As steel is the most versatile material for producing shoes, it can be modified to create surgical and therapeutic shoes to help alleviate problems of disease, injury or conformational abnormalities (Williams and Deacon 2001). Humphrey (1995) stated that the most common types of steel shoes were, plain stamped shoes which were a simple shoe constructed from a flat bar of steel with just the nail holes punched in, and usually having a clip. Concave shoes are the most popular for riding and competition horses, they are made from steel which has already had a groove made in it, the inner edge of the steel is also sloped. This gives the finished shoe better grip and reduces the weight. Fullered shoes are also made from flat bar steel which has a groove forged into it called fullering. These types of shoes are harder wearing than concave shoes but weigh considerably more. Light steel shoes are made from the same rolled steel as a concave shoe but the section of steel is thinner and not as wide, this makes it very lightweight for a steel shoe. The only other shoe which is lighter is the aluminium shoe. The light steel and aluminium types of shoes are most commonly used on racehorses which reduces the weight on their hooves when racing thus helping them to run faster Gait analysis. Equine locomotion has attracted clinical interest since early photography conducted by Muybridge in the late 19 th century, he was the pioneer of equine biomechanics by producing the first moving pictures of a horse showing a moment of suspension in Mark Wood Dip WCF, FdSc. April 2013! Page 9

10 the trot stride, where the horse was completely off the ground. The mechanics of movement also known as kinematics or more properly, biomechanics describes the study of horse movement, which as a science has found new importance in recent decades, partly because of difficulties in equine lameness diagnosis. This had led to many forms of technical gait analysis appearing, such as force plates, treadmills, video and photography (Smythe 1993). Advances in technology have enabled scientists to measure a wide range of gait related variables in a quantitive manner, therefore facilitating repetitive and objective analysis (Clayton 1997). Back and Clayton (2001) stated gait analysis in horses applies measurement techniques to quantify the characteristics of locomotion. Kinematic analysis describes the movements of the limbs and body in terms of timing, distance and angular variables. Hildebrand (1965) also noted that the horse is more versatile in the selection of gait than any other quadruped, although the boundaries between different gaits may be arbitrary and often based on factors of breed and style rather than on differences in general manner of movement of the legs. Muybridge (1887) suggested that trot is characterised by the more or less synchronous movements of the digital limb pairs. Gait analysis in horses is useful in both clinical and performance spheres. Clinical analysis involves an objective, repeatable and standardised protocol which would be a recordable lameness evaluation. This can be useful tool during initial diagnosis or for assessment of progress during initial orthopedic treatment or rehabilitation programmes (Liljebrink and Bergh 2010). Performance horses which went to the Olympic games in London 2012 were assessed before shoeing so the farrier could evaluate their movement and shoe the team horses according to their individual conformation. The biomechanics of locomotion are divided into two groups, kinematics and kinetics, kinematics is the study of movement describing three dimensional linear and angular displacements of the limbs. Kinetics studies the forces that are generated to resist or produce locomotion are absorbed during locomotion (Marlin and Nankervis 2002). Common examples of kinematic variable analysed in the horse include stride length, stride duration, stride frequency and carpal and tarsal angles. Kinetic forces are Mark Wood Dip WCF, FdSc. April 2013! Page 10

11 generally invisible so assessments using analysis systems must potentially measure vertical, horizontal or rotational forces (Weishaupt et al 2010). Chapter 2. Literature review Introduction. The research methods used for this study included the internet, equine veterinary journals and Myerscough college library. The internet research utilised scientific paper specific search engines, Science Direct, Wiley on-line, Ivis and Google Scholar. The key words searched were stride length, locomotion, kinematics, gait analysis, aluminium shoes, show horses and shoe weights. The nearest studies that resemble this one was (Clayton 1994 and Galisteo et al 1997). In both these studies the horses were trotted along a defined line and plotted stride length using a software program. One other similar study, Roepstorff et al (1999) concluded that stance time was not significantly changed between the horse having a shoe on or not. They describe in their discussion that the significant differences in movement were mostly related to swing phase parameters but there was no specific notes on how the horses moved in the swing phase Marker placement. In current literature, marker placement has not been standardised which means that researchers use different methods of placing the markers. The most popular methods tend to concentrate upon the joints of the limbs. In Preedy et al s (2001) study the researchers used markers on both fore feet of one horse. As the camera was recording from the left side of the horse, the assumption would be lateral hoof wall on the left fore and the medial hoof wall on the right limb were the locations, but this was not stated. This study used the marker positions used by Buchner et al (1997) and Back and Clayton (2001). Buchner et al (1997) used 15 linked segments using Mark Wood Dip WCF, FdSc. April 2013! Page 11

12 reflective markers adhered to the skin over palpable skeletal landmarks on the left side. These markers estimated the centre of rotation of the joints. This was also supported by the work done by Cleburne et al (2001), who analysed three thoroughbreds at gallop on a treadmill to measure stride duration before and after fatigue had set in. Roepstorff et al's (2009) study, used one hoof marker placement on the lateral wall of the left fore, they performed their study on seven elite horses ridden on a treadmill with a mean age of 14 years, height 1.7m and body mass of 609 kg. All the above studies used retroreflective markers and an infrared kinematic system called ProReflex. The reflective nature of the markers made it easier for the camera to pick them up. The sample size of all theses studies was limited so their validity and reliability could be questionable. Rogers et al (1999) did not use markers on the limbs or hooves, they also did not describe which part of the hoof was used for the dynamic analysis data, this cast doubts on the validity of the study. The general findings from the literature indicated that the choice of marker placement is dependent on the study being conducted. Lanovaz et al (1999) and Lanovaz et al (2001) just referenced the work done by Clayton et al (1998) and did not specified the hoof marker placement. Burn et al (2001) were investigating hoof deformation, so used a larger number of smaller spherical plastic beads as markers. Five beads were glued in a line up the dorsal wall of the hoof, two on the lateral wall and two on the shoe nearer to the heels. Back and Clayton (2001) also suggested that the markers should be placed over the joints stating the most distal marker should be placed over the distal interphalangeal joint. This would place the marker a third of the way down the hoof capsule, in line with the bone column of the hoof pastern axis. This was the method of hoof marker placement used in this study shown in (Appendix 1 and 6), which was supported by (Buchner et al 1997). The reason for choosing this method was it was the best way of repeatability and accuracy, in the opinion of the researcher this would produce a consistent position which would increase the validity and reliability of this study. Mark Wood Dip WCF, FdSc. April 2013! Page 12

13 2.3. Camera methods. Camera technology has improved over time and this can be clearly seen whilst reading the literature as the older papers used slower cameras whilst some of the more recent papers used high speed cameras. High speed cameras give a much clearer picture when each frame is assessed during the movement, allowing the marker on the hoof to be easily identified. High speed cameras are also used for recording small amounts of movement such as the contraction and expansion of the hoof capsule during the stance phase of the stride. These kinds of movement are difficult to detect by the naked eye and give a clearer insight. Clayton et al (1994), preferred to use a high speed camera operating at 150 frames a second, the camera was set up with access perpendicular to, and 25 metres from, the horse s line of motion. The lens was at a height of 1.2 metres and the field of view was 8 metre wide, which was sufficient to record at least one, and usually two strides at each pass. A calibration stick was recorded in the plane of motion, scaling the linear measurements, the disadvantage of using a stick is that there may not be a suitable place to align it in the camera shot where the horse will be trotting along. Back and Clayton (2001) used a self standing rectangular frame or a linear ruler for calibration which was positioned along the horse s line of progression. The calibration marker is a point of reference so that an exact measurement for gait analysis can be obtained. This study also used a standard camcorder that recorded 25 frames a second in PAL format, they decided against a high speed camera due to the lighting conditions. This is because the lighting conditions become more critical at faster recording speeds and are used for studies of short duration events or rapid movement. Current high speed cameras do not rely totally on well lit conditions to perform. Burn et al (2001), studied the front left hoof of the horses in their study, each horse was trotted in a straight line at a constant speed, whilst the marker position was recorded at a rate of 240 frames a second, this paper was replicated in this study as part of the camera method protocol. The only difference in this study was that the most suitable distance for the camera away from the calibration markers to obtain Mark Wood Dip WCF, FdSc. April 2013! Page 13

14 one to two full strides, was 2.5 metres. The camera used was a Canon IXUS 1000 HS, which on high speed filmed 240 frames per second. The lens was at a height of 8 cm, the calibration box used for this study had markers on each of the corners, measuring 50 cm in length and 16 cm width (Appendix 2). Rose et al (2009), used a 50 Hz digital Sony video camera perpendicular to the trot up line to measure range of motion and stride length. The measurements were averaged from four repetitions, then assessments were taken from the horses which were trotted in hand to obtain the horses natural gait rather than been ridden on a treadmill The use of force plates and treadmills. There has been different studies performed with the use of force plates concentrating on the stance phase of the stride, which measure ground reaction forces, (Roepstorff et al 1999, Burn et al 2001 and Eliashar et al 2002). Force plates were first introduced to equine analysis in the 1970 s and have in one form or another been extensively used in the past 20 years (Marlin and Nankervis 2002). A force plate is a steel plate which has been recessed into the ground, it is then covered with a non slip material, usually rubber. During the stride cycle, toe components are of particular interest in relation to ground reaction forces. The force generated by the initial impact of the hoof has been associated with soft tissue injuries and the force related to the loading phase of stance, which will determine the propulsive forces generated in that limb (Parson et al 2011). Back and Clayton (2001) stated when the horse lands on the plate during the stance phase of the stride, the forces are detected by transducers, converted to electrical impulses and the variables measured then recored. Force plates provide valuable information on the stance and contact phase of each leg during movement and can calculated the weight bearing capacity of each limb, indicating how much each limb contributes to propulsion (Peham et al 1999). Applying Newton s 3 rd law of motion, which states that for every action there is an equal and opposite reaction, force plates can be used to study the forces the limb Mark Wood Dip WCF, FdSc. April 2013! Page 14

15 applies to the ground and hence the forces the ground applies to the limb, (Parsons et al 2011), for example when a horse s limb strikes the ground during locomotion, it will apply force to the ground surface and will receive a reciprocal force generated from the ground into the limb. Treadmills can be a useful tool that can help regulate and control a particular gait as the speed and the slope of the belt is determined by the operator (Back and Clayton 2001). It is necessary to accustom the horses to the treadmill before the study begins, this will allow the horses to trot in a relaxed manner and give the results more validity. It will usually take a horse two sessions before measurements can be taken as they will adapt rapidly at trot (Back and Clayton 2001). It has been demonstrated that the length of stride was longer on a treadmill than at the same speed on a track (Barrey et al 1993 and Courouce et al 1999). The authors Roepstorff et al (1999), Pardoe et al (2001) and Eliashar et al (2002) all used force plate analysis and Pro Reflex video system, but used a variety of surfaces to cover the force plate varying from sand, rubber to concrete. Papers analysing horses on treadmills include Albernaz et al (2009) and Roepstorff et al (2009). (Roepstorff et al 2009) studied seven dressage horses whist ridden at trot, comparing left and right rising trot. Albernaz et al (2009) assessed the kinematics, at walk of seven Arabian horses on a treadmill with toe and heel elevations against a normal shoe. This paper was very brief with little detail on the camera and marker placements used. The authors stated that by adding a 6º toe elevation a reduction of swing time and stride length were produced, and the heel elevation produced an increased stance time. It would have been more interesting to see some data on the horses assessed in trot and how this would affect foot flight. The lack of information in this paper casts doubt into its reliability and validity. For this study a treadmill was not chosen due to the inconvenience it would cause to the owners, and horses of traveling them to a treadmill. The most sensible method for protocol was to trot the cases up in hand at a location that the horses were familiar with and comfortable. Mark Wood Dip WCF, FdSc. April 2013! Page 15

16 2.5. The most appropriate gait and speed for gait analysis. The horse s body can be divided into multiple segments which interarticulate with each other to produce motion. The movement of the horse is defined by the four limbs coordinating to produce the recognisable gaits. Each gait has different stride patterns and is composed of a stance phase, whilst the limb is in contact with the ground, the swing phase when the limb is lifted off the ground, and swings forwards in preparation for the next stride (Marlin and Nankervis 2002). The horse s stride is also composed of the protraction or flexion and retraction or extension of the limb. A good quality trot is recognised by a long swing phase duration and a suspension phase with more retraction of the fore limb, (Back and Clayton 2001). Clayton (1994) suggested trot as the most appropriate gait to use for gait analysis since the trot is a symmetrical gait, with the footfalls of the contralateral, left and right limbs begin evenly spaced in time (Hildebrand 1965). The diagonal limb pairs swing more or less synchronously giving the trot a two beat rhythm (Clayton 1994). This is supported by the Federation Equestre Internationale, stating trot was decided as the gait of choice because it has a two beat diagonal, symmetrical gait in which the horse s body weight is traveling down each diagonal pair of the fore and hind limb separately which makes analysis easier and more practical to analyse. Lanovaz et al (2001) also stated that trot is the most important gait in studies of both performance and lameness. Audigie et al (2001) suggested that the most comfortable speed at trot in their study ranged from 3.0 to 3.5 m/s, Weishaupt et al (2001) confirmed that the most appropriate trotting velocity, to obtain a natural gait, was a speed of 3.5 m/s, this was obtained by analysing the horses on a treadmill set to that speed. Usually if a horse is trotted by a confident handler, at a speed that is comfortable to that particular horse, the strides remain constant and even, which was the method adapted for this study. As the trot is a two beat symmetrical gait, it is assumed that both fore limbs produce the same length of stride. For this study the left fore was chosen for analysis. Mark Wood Dip WCF, FdSc. April 2013! Page 16

17 2.6. Different horse shoe material. Pardoe et al (2001) studied the effects of shoe materials on the kinetics and kinematics of foot slip at impact on concrete. This paper stated that eight horses were shod with steel, plastic, and rubber on their fore feet. The study was undertaken on a concrete covered force plate and steel shoes were fitted to the hind feet throughout. All shoes were fitted with adequate length and width for each individual horse. When comparing the weights of the shoes, the steel were 50% heavier than rubber and 100% heavier than plastic. The difference between the plastic and steel shoes were of particular interest to the researcher as this was the nearest study to the one conducted for this dissertation. The authors found that there was no significant differences between the mean values in slip time distance between all three types of shoes. It would have been interesting if they had followed up their study with some kinematic data on stride length as this would have been a valuable study to use as a comparison for the study performed for this dissertation. Alternative materials for horse shoes seem to have become very fashionable. Plastic, aluminium, and rubber have all been developed with their manufacturers claiming that their product is the holy grail (Williams and Deacon 2001). A common problem with aluminium shoes is that because of the softer nature of the metal, the horse s body mass is driven down into the metal causing a grove in the shoe at the heels, this can prevent the hoof capsule from functioning correctly by locking the heels into the shoe (Appendix 7). It is presumed that as aluminium shoes are softer and lighter, they reduce concussion, it is the researcher s thoughts that this is counteracted on hard surfaces due to the extra grip and consequent jarring of the hoof capsule, which in turn will cause concussion on the joints in the distal limb. This is supported by Colles and Ware (2010) who stated that the disadvantages of aluminium shoes were that they are quite soft and wear quickly. They also tend to grip the hoof and the ground which can result in increased concussion on the foot, on hard surfaces. They also stated that aluminium is about one quarter the weight of mild steel, and is primarily used for racing plates, although it is some times used for other special purposes such as show horses. Mark Wood Dip WCF, FdSc. April 2013! Page 17

18 More recently horse shoes have been designed from different materials in an attempt to alter the grip or impact attenuation of the horseshoe (Wilson et al 1992). These materials have different frictional properties which effect the distance the foot slides after impact and before it comes to rest (Heidt et al 1996). The use of alternative materials needs more study and research especially into their effects on hoof capsule function and equine locomotion Stride length. When using photography Clayton (1994) described that stride length was taken from the first frame which showed lift off, in which the hoof was clear of the ground, and finished with the impact of the hoof with the ground. She studied stride kinematics at collected, working, medium and extended trot, and found that speed increased significantly in each different trot phase and that the speed was changed primarily as a result of adjusting the stride length. This statement is supported by Marlin and Nankervis (2002), who suggested that when horses increase their speed within any gait, they tend to accomplish it by first making an increase in their stride length. With this study in mind it was very important to try to ensure that the horses in this study trotted at the same constant speed for all the trot ups and a mean value calculated. This helped eliminate some of the error due to fluctuations in speed which could affect stride length and the validity of this study. Interestingly, Rogers et al (1999) found that in their study even though the horses were traveling at a higher velocity on the third inspection at a three day event, they had a shorter stride length characterised by a decrease in retraction of both forelimbs due to fatigue. Balch (1997) stated that despite traditional expectations of farriers and trainers lengthening the hoof did not affect stride length. It was a common belief in the racing industry that by lengthening the toe of the horse s hoof, a longer stride length would be produced. In Rogers et al s (1999) study initial ground contact was taken as the first frame, which showed the beginning of the stride, thereafter the hoof lifted off the ground into swing phase followed by the hoof contact to the ground again, which was the last Mark Wood Dip WCF, FdSc. April 2013! Page 18

19 frame of the stride to be measured. This was the protocol method used for this study by the researcher when analysing the video footage on Ontrack equine gait analysis software. It was the thoughts of the researcher that this method would be the easiest to reproduce on all sixty trot ups to be analysed, increasing the reliability of the data. The stride length is the distance travelled by the horse s centre of mass during one stride, or the distance between successive prints of the same foot (Marlin and Nankervis 2002). Whilst Albernaz et al (2009) stated that toe elevation determines the length of the lever arm over which the limb rotates as well as the timing of hoof take off. Rose et al (2009) performed a well constructed study which compared a three and six days a week stretching regime, with a control group which received no stretching. The results showed that by performing a 3 day stretching regime the range of motion (ROM) improved the shoulder joint. The ROM of the hock and stifle in the 6 day stretching regime were significantly lower than in the three day group which could be the result of muscle stiffness. No changes occurred in the length of stride within either of the control groups. The study appeared to be valid due to the amount of protocols set in place to control the reliability of the study. The results of this study for stride length can be seen in chart form (Fig 4.5 and 4.7) Flight patterns It was demonstrated by Yxklinten et al (1998) that a horse can alter its limb flight patterns and foot placement to compensate for differing shoeing states by altering joint angles, joint angular velocities and foot velocity at impact. Pardoe et al (2001) studied the effect of shoe material on kinematics and kinematics of foot slip at impact on concrete. The authors concluded that slip time and slip distance were similar for all three shoe types, but the craniocaudal, decelarative force after impact was significantly reduced in the plastic shoes. This did not support their original hypothesis and suggested that horses may alter their gait to compensate for the grip characteristics of the shoe that is fitted, in order to maintain a constant slip time and distance. The study was performed on 8 clinically sound horses with good hoof Mark Wood Dip WCF, FdSc. April 2013! Page 19

20 balance. The different shoes were applied in a random sequence and 8 strikes on the force plate for each shoe recorded. However the authors made no comments of how the hooves were trimmed and if the data was taken on the same day for each type of shoe, which could impact on the validity of their study Hoof trimming protocol. In Roepstorff et al s (1999) and Lanovaz et al s (2001) studies they stated that the foot trimming was performed by an experienced farrier whilst the studies performed by Eliashar et al (2002) stated two different farriers applied the shoes. The first farrier from the household cavalry applied the toe clipped and side clipped shoes whilst the second farrier, who applied the shoes used the process of fitting from the paper by Ovnicek (1997). Each of the different types of shoe were applied at three week intervals and assessed a week after shoeing. This would cause doubt for the reliability and validity of this study. The paper also had good graphs and tables of data which made it easier to understand. It would have been interesting if the authors had also analysed the slip time of an aluminium type shoe to see how much extra grip and what the consequence of jarring would have been as a result of the softer nature of the metal. The protocol used for this study was taken from a combination of Balch et al s (1997), Eliashar et al (2002) and Stashak et al (2002) Shoe weights. The distal limb of the horse has evolved to become very light in weight. One of the goals when shoeing a horse is to keep the weight of the shoe as light as possible (Balch et al 1997). This decreases its inertia, which reduces energy expenditure in protracting and retracting the limbs. Butler (1995) stated that 1oz at the foot is equivalent to 30oz at the withers, and that the maximal weight that should be added to the hoof is 5 to 10oz. Willemen et al (1999) investigated the influence of shoeing on stride kinematics, of young horses that were shod for the first time. The average weight of the horses was 516kg and the average weight of the shoes were 478g. Mark Wood Dip WCF, FdSc. April 2013! Page 20

21 Stride duration and the relative swing phase duration were longer in the shod horses, but stride length was not significantly different. Balch et al (1996) doubled the weight of the shoe from g to g, which did not result in changes in stride length, stride duration or breakover time. Butler (1995) stated that toe weight would improve the flexion of the carpus and heel weight would improve the reach of standardbred horses. Willemen et al (1994) applied 88g toe weights to the fore feet of trotters, the effects of toe weights on stride kinematics varied with the individual locomotion pattern. Weight attached to feet increases the height which the feet are raised from the ground through greater limb flexion. This is a well known effect used to improve the performance of gaited and carriage horses. This is the opposite to the trot gait which the show horses are require to move. Show horses are preferred to move with a lower arc of flight with an extension of the limb in the final stage of the swing phase. The effects of shoeing and weight on the distal limb on gait quality have been studied and shown to mainly affect the swing phase variables of the trot (Roepstorff et al 1999). Back and Clayton (2001) stated that the effect is greater with a more distal placement. The weight of a shoe is likely to affect both the energetics and the kinematics of locomotion. For this study the average weight of the aluminium shoe was 155.5g and the steel mean value was 449.5g, the average weight of the horse was 600kg Statistical analysis. There are different types of statistical tests which can be performed depending on what data needs processing and how many test groups are being analysed, in this study there were two main groups the aluminium and the steel shoes. The result data figures were down loaded onto a Microsoft Excel spread sheet and analysed for normality of distribution. The figures were assessed through histogram graphs and an ANOVA test on the descriptive data were performed between the mean values of each horse and was calculated using minitab 16. Descriptive statistics (mean, median, mode and standard deviation) were calculated for the variables in each Mark Wood Dip WCF, FdSc. April 2013! Page 21

22 horse and both types of shoe where possible. Pardoe et al s (2001) study used analysis of variance (ANOVA) test, using statistical software program to analyse foot slippage with three different types of shoes. ANOVA tests can be used when there are two means to compare, the t test and the ANOVA F-test are equivalent. The relation between ANOVA and t is given by F = t 2, ANOVA is used when the researcher wants to study the interaction effects among the treatments. With repeated measurements ANOVA is used when the same subjects are used for each treatment group. Rogers et al (1999) used a paired t test, whilst Pardoe et al (2001) performed a post hoc t test. Roepstorff et al (1999) used a Wilcoxon matched pairs test, which is a non parametric hypothesis test, used for comparing matched samples or repeated measurements on a single sample. It can be used as an alternative to a students t test, which for matched pairs, or t test for dependent samples when the population can not be assumed to be normally distributed. Clayon (1994) used a paired t test for left and right, bilateral, symmetry with a probability value of 0.05 alpha. The hypothesis that there was no difference in the measured kinematic variables between collecting, working medium and extended trots was tested using an analysis of variance and that Waller-Duncan-Bayes K-ratio t tests at a probability level of 0.01 Alpha. Mark Wood Dip WCF, FdSc. April 2013! Page 22

23 Chapter 3. Methodology Study aims and objectives. The purpose of this study was to compare kinematic characteristics of horses with two different weights of shoes. There has been very little research on the effects of shoeing larger horses with aluminium shoes and if any differences, in stride length, occur when compared with steel shoes. The consensus within the showing community is that a lighter aluminium shoe, will give that particular horse an advantage in dynamic motion by providing a greater length of stride compared to a heavier steel shoe. Therefore the aim of this study is to identify the most appropriate material for shoeing show horses, and to calculate which shoe gives a horse the preferred movement Hypothesis. A hypothesis from ancient Greek hypotithenai, means to put under or to suppose, and the plural is hypotheses. For a hypothesis to be a scientific hypothesis, it requires that one can test it. A hypothesis is usually the beginning statement of many projects, Verma and Beard (1981) defined it as a tentative proposition which is subject to verification through subsequent investigation. It may also be seen as the guide to the researcher in that it depicts and describes the method to be followed in studying the problem (Bell 2010). In many cases hypothesis are hunches that the researcher has about the existence of relationship between variables, bearing this in mind the hypothesis makes a statement of relationships between the variables so the researcher has a guide to their original hunch and something to test. The hypothesis for this study was that a lighter aluminium shoe will give a more preferential stride action on the show horse compared to a more traditional steel shoe. Mark Wood Dip WCF, FdSc. April 2013! Page 23

24 3.3. Introduction to methodology. Methodology is defined as how one approaches a study of a phenomenon, whilst the methods are a more specific way to collect data. It is generally accepted that there are two main research paradigms or theoretical frameworks; quantitative, deductive reasoning and qualitative, inductive reasoning (Gilbert 2008). Epistemology is the study of the nature of knowledge, this is split into two categories of deductive and inductive investigations. Deductive investigations are based on knowledge on a subject that already exists i.e a known theory. Inductive investigations are based upon knowledge of a subject that is not assumed. Many researchers believe that when planning a research study the researcher should be designing either an inductive study or a deductive study, however, there is definitely a place for using a combination of elements from both, as discussed by (Gilbert 2008). Quantitative or deductive research involves beginning with a hypothesis drawn from existing theory, then to follow this with the investigation of two or more variables, experimentally to establish relationships between the variables (Feldman 1998). Qualitative researchers aim to gather an in depth understanding of behaviour and the reasoning that governs such behaviour. Qualitative methods investigate why and how decisions are made. Qualitative research explores motivations, emotions and prejudices which can be used to support or reject hypothesis as well as answering research questions (Kumar 2010). A quantitative research paradigm was selected for this study as it was a comparison between two variables. Both inductive and deductive investigations were used when conducting this study Reliability and validity. Reliability is the extent to which a test or procedure produces similar results under constant conditions on all occasions. The study needs to be repeatable by different researchers so the methodology needs to be consistent and reliable, which is increased by the standardisation of all possible variables in the study (Bell 2010). Mark Wood Dip WCF, FdSc. April 2013! Page 24

25 Validity is usually defined as whether an item or instrument measures or describes what it is supposed to measure or describe, Sapsford and Jupp (1996), defined validity to mean, the design of research to provide creditable conclusions. If an item is unreliable, then it will also lack validity. If the findings of research are invalid they are not credible and therefore worthless (Cohen et al 2000) Sample size and inclusion criteria. A pilot study was performed with a sample size of ten show horses to measure any differences in the length of stride between aluminium and steel horse shoes. A show horse is classified as a horse of either gender of a height of 15 to 17 hands. When these horses are shown, a judge will assess the horse for conformation, locomotion action and temperament. All ten horses main use currently is that of a show horse in the summer show season. All the horses in this study were selected as they were sound and of good conformation with good quality hoof capsules, giving the study better validity and reliability. This also limited the risks of causing any unnecessary discomfort. The horses were monitored for soundness throughout the study and if any had become unsound they would have been removed from the study Materials and methods. 10 clinically sound show horses, 3 mares and 7 geldings aged 7 to 16 years and weighing 490kg to 706kg were used for this pilot study (Fig 4.1). The horses were assessed at the owners yards at the time of shoeing, when the showing season was finishing. The timing of this study was selected as this was when the horses were due to come out of aluminium shoes and back into steel shoes for the winter. To reduce the variables and increase the validity of this study all the horses were trimmed by the researcher, who ensured that the trimmed heel terminated near to the widest part of the horny frog, which gave both shoes the same amount of support. The shoes were both fitted in the same manner with the toe of the shoe in line with Mark Wood Dip WCF, FdSc. April 2013! Page 25

26 the wall at the dorsal hoof wall, and was fitted to the outline of the bearing border with caudal support when needed. The researcher attached a 15mm round self adhesive marker on each of the horses. It was placed on the mid point, lateral aspect of the left fore hoof capsule (Appendix 1 and 6). This was the point of reference for the gait analysis software to measure the horse s stride length. The first pair of aluminium front shoes were attached to the hoof capsule using only four nails and using old nail holes where possible to limit any extra nail holes and discomfort (Appendix 6). Video footage was taken of the horse trotting on concrete, following a defined line, four times by the same experienced handler at a speed comfortable for the horse. The aluminium shoes were carefully removed and the second pair of steel shoes were attached for another four trot ups. The horses remained in the steel shoes for the duration of the winter and steel shoes were fitted to the hind feet throughout the study. The video footage was analysed using Ontrack Equine software to measure the stride length. The researcher measured each horse s stride beginning the moment after the hoof contacted the ground during stance phase all the way through the swing phase until the limb was again in it s stance phase, just after first contact. The results were compared and analysed for statistical data Hoof trimming protocol. Appropriate hoof preparation and shoe fit are integral to soundness and performance (Butler 1985 and Balch et al 1995a,b). This solid statement is supported by Stashak et al (2002) who also stated the hoof capsule is malleable and the manner in which it is trimmed and shod can have marked effects on performance and soundness of the equine athlete. The protocol followed in this study was taken from Stashak et al (2002), who stated balance as it applies to horseshoeing is three dimensional and may be defined as an equal weight or force around the centre of gravity which is identical with that of the foot. Balch et al s (1997) theories were also used, by adapting the technique of geometric limb axis oriented procedure that prepares the ground surface of the wall perpendicular to the axes of the cannon bone and Mark Wood Dip WCF, FdSc. April 2013! Page 26

27 phalanges. All the front feet were prepared so that the trimmed heel terminated close to the widest part of the frog (Eliashar et al 2002). Following these methods helped to give each of the different shoe weights the same amount of heel support Standardisation. The researcher performed a trial study on three horses initially to assess the variables and reliability of the study. When analysing the initial data with Ontrack equine software it became apparent that the quality of the digital camera was struggling to accurately pick up the marker placement on the hoof capsule. The researcher decided to suspend the research and obtain a higher quality camera. The researcher in this study controlled most of the variables from choosing the horses, to hoof preparation, shoe application, marker placement, camera operation and gait analysis. The only other human intervention was that of a familiar hander to trot the horse at a comfortable speed in a relaxed manner. Whilst analysing the video footage of the trot ups, it became apparent that one of the trot ups on three of the horses was not showing a full stride in the middle of the shot which seemed to make the accuracy of the stride measurements inconsistent. These videos were excluded and only three trot ups for each of the shoes per horse was used for the data analysis Data analysis. The data were collected form the 10 horses when they were due to go into the heavier steel shoes at the beginning of the winter. Within each stride every limb has a stance phase when it is in contact with the ground, and a swing phase when it moves forward in preparation for the next stance phase. It is the length of the swing phase which was of interest. The first assumption that should be checked is that the data is normally distributed. Basic statistical tests for normality should be checked before any other statistics are performed. Statistical calculations can be used to describe the likelihood of the results arising from chance, the results of which are described as the p-value. If the Mark Wood Dip WCF, FdSc. April 2013! Page 27

28 p-value is less than 0.05 it is classed as statistically significantly, the lower the p- value, the greater the likelihood that the relationships are based on the independent variable (Crombie 1996). Once the data was collected the researcher calculated some basic quantitive statistics to form the numerical data extracted from the study results. Descriptive statistics for both aluminium and steel shoes were generated in Microsoft Excel 2010 (Fig 4.3 & 4.4). Normality of distribution was assessed through histogram graphs generated from the data analysis on Microsoft Excel The differences between passes were calculated by subtracting the results from passes 1-2, 2-3 and 1-3. Analysis of the arithmetic means data in this study was completed using a two-way, analysis of variance (ANOVA) test in minitab 16 (Fig 4.6) which is a powerful statistical test used for independent, numerical data. A pair t test on the differences between passes and a pair t test between the mean values of each horse was considered, but rejected and a two-way ANOVA on minitab 16 was performed Ethical considerations. This study was conducted under the ethical guide lines and approved by Myerscough College ethics committee, University of Central Lancashire. It was important to consider the ethical implications at all stages of the research study and not impose any stress pain or suffering upon any of the horses involved in the study. Researchers need to satisfy themselves that they have done everything possible to ensure that your own research is conducted in a way which complies with your own ethical principles (Bell 2010). A client Information letter and questionnaire was given to the owner and a signature indicating consent obtained. The letter made the owner aware of what the study was about and that their information would be kept private and confidential (Appendix 3). Their horses were shod by a qualified registered farrier at a time when they are due to have their feet trimmed and shoes replaced which kept the amount of intervention to a minimum. The client had the right to remove their horse from the study at any time. Mark Wood Dip WCF, FdSc. April 2013! Page 28

29 Chapter 4. Results Group selection All the horses were selected due to their soundness, conformation, temperament and good quality hoof capsules. The selected horses were all used for showing in the summer season, the research had taken place at the end of the showing season There was no particular age, breed, gender or weight used as a preference, these factors were all random. Four of the subjects 3 to 6 belonged to the same owner, which made obtaining the video footage more practical, as they were all shod on the same day at the same location. Horses 7 to 10 were also stabled on the same yard but had different owners and were shod on different days. The weights of the horses were measured in kilograms (kg), ages in years and height in both hands (hh) and centimetres (cm). The weight of the shoes were measured in grams whilst the stride length was in centimetres Group details Ten clinically sound show horses, three mares and seven geldings, the commonest breed was the Irish draft cross Thoroughbred (ID x TB), with seven of the horses ten horses. The standard deviation from the mean was calculated for their ages of between 7 to 16 (mean ± s.d 10.4 ± 2.55 years), weighing from 490kg to 706kg (mean ± s.d 600.3kg ± 79.28kg) and heights of 157.5cm to 170cm (mean ± s.d 163cm ± 4.68cm) which converts to 16 hands ± 1.84 inches. Fig 4.1 Details of case studies. Case Age Height Weight Breed 1 9 years 16 hh 528 kg ID x TB 2 10 years 16 hh 490 kg TB 3 7 years 16'2 hh 665 kg ID X TB 4 11 years 15'3 hh 706 kg ID X TB 5 12 years 15'2 hh 608 kg ID X TB 6 12 years 15'3 hh 698 kg ID X TB 7 16 years 16'3 hh 624 kg ID X TB Mark Wood Dip WCF, FdSc. April 2013! Page 29

30 Case Age Height Weight Breed 8 9 years 16 hh 624 kg ID X TB 9 10 years 15'2 hh 490 kg TB 10 8 years 16'3 hh 570 kg WB X TB Mean 10 years 16 hh 600 kg ID X TB Mode 16 hh ID x TB Median 10 years 16 hh 616 kg ID x TB Standard deviation 2.55 years 0.47 hh kg 4.3. Shoe weights. The shoe weights were measured in grams using digital weighing scales and arithmetic mean values calculated, the aluminium shoes were between 90g and 210g (mean ± s.d 155.5g ± 40.1g) in contrast to the weight of the steel shoes which were 325g to 610g (mean ± s.d 449.5g ± g). This made the average weight of the aluminium shoes one third the weight of the steel shoes used for this study. Fig 4.2 Chart showing the weight comparison of aluminium and steel shoes horse 1 horse 2 horse 3 horse 4 horse 5 horse 6 horse 7 horse 8 horse 9 horse 10 Aluminium weight g Steel weight g Mark Wood Dip WCF, FdSc. April 2013! Page 30

31 4.4. Stride lengths. The video footage of both the aluminium and steel shoes were downloaded and analysed using Ontrack equine software program. Following examination of the raw data for stride length comparison (Appendix 4), the statistical analysis highlighted that there was a significant difference between the two types of shoes Fig 4.3 Descriptive data of each trot up in centimetres. Each trot up Mean Standard Error Median Mode Standard Deviation Sample Variance Kurtosis Skewness Range Minimum Maximum Sum Count Fig 4.4 Descriptive data of each case. Aluminium cases Mean Standard Error Median Standard Deviation Sample Variance Skewness Range Minimum Maximum Sum Count Mark Wood Dip WCF, FdSc. April 2013! Page 31

32 Steel cases Mean Standard Error Median Standard Deviation Sample Variance Skewness Range Minimum Maximum Sum Count Fig 4.5 Frequency of stride length for both types of shoes Frequency More STRIDE LENGTH Aluminium Steel 4.5. Descriptive statistics A different approach was considered than a paired t test on excel The researcher decided to use mini tab 16, and a parametric test assuming an abnormality was performed. A two way ANOVA test was used on the data giving a probability value of P=<0.001 showing a significant difference between the two types of horse shoes (Fig 4.5). The overall result was that we can accept the hypothesis that there is a difference with a P value of p = <0.001 and F 3,8 = No statistical rules had been broken whilst analysing the data set. Mark Wood Dip WCF, FdSc. April 2013! Page 32

33 The reliability and variation of measurements were a consideration when calculating the results. When the average, (arithmetic mean) was presented it is scientifically correct to specify the error associated with the value quoted. Statistically the term error refers to the inherent genetic and environmental variations, plus any limitations on the equipment and sample size. The error figure attempts to quantify the reliability of the sample measurements taken, as shown with the error bars in (Fig 4.6). Caution is advised when encountering interactions, Test interaction terms first and expand the analysis beyond ANOVA if interactions are found. Texts vary in their recommendations regarding the continuation of the ANOVA procedure after encountering an interaction. Interactions complicate the interpretation of experimental data. Neither the calculations of significance nor the estimated treatment effects can be taken at face value. A significant interaction will often mask the significance of main effects. There was no interactions found in this test. Fig 4.6 Two-way ANOVA: Length (cm) versus Shoe, case Source DF SS MS F P Shoe P<0.001 case Interaction Error Total S = R-Sq = 87.74% R-Sq(adj) = 81.92% Individual 95% CIs For Mean Based on Pooled StDev Shoe Mean Al (------*------) St (------*-----) Individual 95% CIs For Mean Based on Pooled StDev Mark Wood Dip WCF, FdSc. April 2013! Page 33

34 case Mean (---*---) (---*---) (---*---) (---*---) (---*---) (---*---) (---*---) (---*---) (---*---) (---*---) Fig 4.7 Stride length chart from Minitab 16 Seven of the horses had a very similar length of stride for both types of shoe. Mark Wood Dip WCF, FdSc. April 2013! Page 34

35 Fig 4.8 Interval plot graph. Fig 4.9 Effects plot for length of stride of the shoe, case and each of the three trot ups. Shows that the mean values for the three trot ups were very similar, indicating that the horses did not produce a longer stride once they had warmed up by the third assessment. Mark Wood Dip WCF, FdSc. April 2013! Page 35

36 Chapter 5. Discussion Standardisation The horses in this study were chosen because they were all used for the showing ring. The majority of the horses were Irish Draft cross Thoroughbreds and were of a similar height which helped with the standardisation of the cases studies. They all had excellent quality hoofs and good conformation Limitations As this was a pilot study, the number of case studies were small and therefore decreases the validity of this study. A larger group sample would reduce the amount of error for statistical results. The horses had been shod at the clients premises due to the inconvenience of traveling them to a single venue. Whilst assessing the data the researcher was concerned that the amount of variance between the stride lengths observed in a single video footage. If a full stride was captured evenly over the direction of the camera, that stride was taken for the data. On some of the videos there were two full strides which were captured in the shot, when measured there was a significant difference in stride length, which implies that there is an anomaly due to the camera angle. The stride which was taken as the measurement for the data, was the one which was the closest to the centre of the shot which would be closer to the camera. With this abnormality noticed on some of the footage, the reliability and validity of this study is questionable Results. The results of the statistical analysis on the data show that there is a difference between the two types of shoe, it's is the researchers thoughts that by looking at the results raw data, any difference between stride length was subjective and no clear difference could be seen in order to to give a definitive answer. Mark Wood Dip WCF, FdSc. April 2013! Page 36

37 5.4. Differences between aluminium and steel shoes. The softer nature of aluminium when horses are ridden on a hard surface could cause unnecessary jarring and stress on the joints of the lower limb. Concussion has been suggested as a factor in the development of injuries to the distal limb (Back et al 1995). Horse owners need to understand that some horses shod with aluminium, will have detrimental effect to their hoof capsules due to the lack of support the aluminium gives (Appendix 7). All the horses in this study had good quality hooves and showed no signs of deterioration during the showing season whilst they were wearing aluminium shoes. Chapter 6. Conclusion and recommendations 6.1. Conclusion Equine gait analysis provides a simple and objective method of standardising the locomotion of the equine. It can be a repeatable and quantifiable method of assessment for both kinematic and kinetic profiles. Gait analysis has the potential of been a complementary tool for the use of lameness assessments and for the training, rehabilitation and pre shoeing plan of performance horses. It could also be used to predict the potential of young horses. Weight which is attached to the distal limb in the way of a shoe, increases the flexion of the limb and thus lifting the hooves further off the ground (Back & Clayton 2001). This could be why showing clients prefer lighter weight shoes, as the preferred way of movement of a show horse is a lower arc of flight which gives the illusion of a longer stride pattern. The weight of a horse shoe does seem to slightly alter the length of stride of show horses, but it could be that the soft nature of the aluminium shoe is detrimental to the soundness and longevity to the horse if they were shod for too long with aluminium Mark Wood Dip WCF, FdSc. April 2013! Page 37

38 shoes. The researcher has observed the larger ID x TB type show horses wear a groove into the bearing border of the metal at the heels of the shoe. This can lock the heels into the shoe and prevent the correct function of contraction and expansion of hoof capsule. The foot also appears to spread at the quarters, which encourages the sole to flatten, and creates an unstable hoof capsule. This in turn can cause bruising, sensitive soles and corns (Appendix 5). It is the thoughts of the researcher that by shoeing these types of horses with a steel shoe, stride length is very slightly altered, but the function and soundness of the hoof capsule is preserved, this seems the most sensible approach to shoeing show horses to prevent lameness and preserve soundness Recommendations for future research. This study did not plot the full arc of flight of the swing phase, but it would be interesting as a follow up study to see if the aluminium shoes had a lower arc of flight. Other areas of study and research I would recommend would be to see how different types of steel shoes change the flight pattern of the fore limbs. It would be interesting to investigate if a horse would have a longer stride with a rolled toe, square toe or roller motion type shoe compared with a traditional toe clipped front shoe. Aluminium shoes could also cause more concussive forces through the limb and joints due to the jarring affect of the softer material. A comparative study which measures the forces induced during locomotion between aluminium and steel shoes would also be very interesting. The different surfaces that a horse will be expected to work on will alter the length of stride and arc of flight, this would also be a good comparative study to undertake to see which surface would be more beneficial to help produce a more preferential stride. Mark Wood Dip WCF, FdSc. April 2013! Page 38

39 REFERENCES Albernaz, R. M., Basile, R. C., Glommed, L. M. W., Dias, D. P. M., Neto, A. D. Q. & Neto, J. C. D. L. (2009) 'Videographic kinematic analysis of equine movements submitted to 6º heel and toe elevation', International Veterinary Information Service. Available from: Accessed on February 9 th 2013 Audigie, F., Pourcelot, P., Degueurce, C., Geiger, D. & Denoix, J. M. (2001) Kinematic analysis of the symmetry of the limb movements in lame trotting horses, Equine Veterinary Journal, Supplement. 33, pp Back, W., Schamhardt, H.C., Savelberg, H.H.C.M., Van Den Bogert, A.J., Bruin, G., Hartman, W. & Barneveld, A. (1995) 'How the horse moves: 2. Significance of graphical representations of equine hind limb kinematics', Equine Veterinary Journal, Supplement. 27 Back, W., Schamhardt, H. C., Van Weeren, P. R. & Barneveld, A. (1999) A comparison between the trot of pony and horse foals to characterise equine locomotion at a young age, Equine Veterinary Journal, Supplement. 30, pp Back, W. & Clayton, H. M. (2001) Equine Locomotion. London: W. B. Saunders Balch, O., White, K., Butler, D. & Metcalf, S. (1995a) Hoof Balance and lameness: improper toe length, hoof angle, and mediolateral balance, Compendium on Continuing Education for the Practising Veterinarian. 17, pp Balch, O., White, K., Butler, D. & Metcalf, S. (1995b) Hoof Balance and lameness: Foot bruising and limb contact, Compendium on Continuing Education for the Practising Veterinarian. 17, pp Balch, O., Clayton, H. & Lanovaz, J. (1996) Weight and length induced changes in limb kinematics in trotting horses, American Association Equine Partners. 42, pp Balch, O. K., Butler, D. & Collier, M. A. (1997) Balancing the normal foot: hoof preparation, shoe fit and shoe modification in the performance horse, Equine Veterinary Education, Supplement. 9, (3), pp Barrey, E., Galloux, P., Valette, J. P., Auvinet, B. & Wolter, R. (1993) 'Stride characteristics of overground versus treadmill locomotion. Acta Anat. 146: pp Barrey, E., Evans, S. E., Evans, D. L., Curtis, R. A., Quinton, R. & Rose, R. J. (2001) Locomotion evaluation for racing in thoroughbreds, Equine Veterinary Journal, Supplement. 33, pp Bell, J. (2010) Doing Your Research Project, 5 th Edition. Maidenhead: Open University Press Mark Wood Dip WCF, FdSc. April 2013! Page 39

40 Buchner, H. H., Savelberg, H. H., Schamhardt, H. C. & Barneveld, A. (1997) Inertial properties of Dutch warmblood horses, Journal of Biotechnology. 30, pp Burn, J. F. & Brockington, C. (2001) Quantification of hoof deformation using optical motion capture, Equine Veterinary Journal, Supplement. 33, pp Butler, K. D. (1985) The Principles of Horseshoeing 2. Laporte, Colorado, USA: Butler Publishing Butler, D. (1995) The Principles of Horseshoeing 2. Farrier science & craftsmanship, 4th Edition. LaPorte, Colorado, USA: Butler Publishing Bystrom, A., Roepstorff, L. & Johnston, C. (2006) Effects of draw reins on limb kinematics, Equine Veterinary Journal, Supplement. 36, pp Cano, M. R., Miro, F., Monitored, J. G., Diz, A., Martin, J. & Galisteo, A. M. (2001) Changes due to age in the kinematics of trotting Andalusian foals, Equine Veterinary Journal, Supplement. 33, pp Clayton, H. M. (1994) 'Comparison of the stride kinematics of the collected, working, medium and extended trot in horses', Equine Veterinary Journal. Vol. 26 (3) pp Clayton, H. M. (1997) Classification of collected trot, passage, and Piaffe based on temporal variables, Equine Veterinary Journal, Supplement. 23, pp Clayton, H. M., Lanovaz, J. L., Schamhardt, H. C., Willemen, M. A. & Colborne, G. R. (1998) Net joint moments and powers in the equine forelimb during the stance phase of the trot, Equine Veterinary Journal, Supplement. 30, pp Clayton, H. M., Lavagnino, M., Kaiser, L. J. & Stubbs, N. C. (2011) Swing phase kinematic and kinetic response to weighting the hind pasterns, Equine Veterinary Journal, Supplement. 43, pp Cohen, L. Manion, L. & Morrison, K. (2000) Research methods in Education, 5 th Edition. London : Routledge Flamer Colborne, G. R., Birtles, D. M. & Cacchione, I. C. (2001) Electromyographic and kinematic indicators of fatigue in horses: a pilot study, Equine Veterinary Journal, Supplement. 33, pp Colles, C. & Ware, R. (2010) The Principles of Farriery. London: J. A. Allen & Co. Ltd Courouce, A., Geoffery, O., Barrey, E. & Rose, R. J. (1999) 'Comparison of exercise tests on different tracks and on an uninclined treadmill in French horses', Equine Veterinary Journal, Supplement. 30, pp Crumby, I. K. (1996) The Pocket Guide to Critical Appraisal. London: BMJ Publishing Group Mark Wood Dip WCF, FdSc. April 2013! Page 40

41 Curtis, S. (1999) 'The principles of hoof balance' In: Farriery - Foal to Racehorse. Suffolk: Newmarket Farrier Consultancy Curtis, S. (2002) Corrective Farriery (Volume 1) - A Textbook on Remedial Horseshoeing. Newmarket: R&W Publications Dollar, J. A. W. & Wheatley, A (1898) A Handbook of horseshoeing and the horses foot. Pf.2; The horse s foot in relation to shoeing, David Douglas, Edinburgh. pp Eliashar, E., Mcguigan, M. P. & Wilson, A. M. (2002) 'A comparison of three horseshoeing styles on the kinetics of breakover in sound horses', Equine Veterinary Journal, Supplement. 34, (2) pp Federation Equestre Internationale. (1991) Rules for dressage events, 18 th Edition. Federation Equestre Internationale, Switzerland. pp Feldman, H.R. (1998) 'Theoretical Framework' In: LoBiondo-Wood, G. & Haber, J. Eds. Nursing Research. Methods, Critical Appraisal, and Utilization 4th Edition. Missouri: Mosby, Inc Galisteo, A. M., Cano, M.R., Morales, J.L., Miro, F., Vivo, J. & Aguera, E. (1997) 'Kinematics in horses at the trot before and after an induced forelimb supporting lameness', Equine Veterinary Journal, Supplement. 23, pp Gilbert, N. (2008) Researcing Social Life. 3 rd Edition. London: SAGE Publications Ltd Heidt, R.S. Jr., Dormer, S.G. Cawley, P.W. Scranton, P.E. Jr., Loses, G. & Howard, M. (1996) Differences in frictional and torsional resistance in athletic shoe-turf interfaces, American Journal of Sports medicine. 24, pp Hickman, J., & Humphrey, M. (1998) Hickmans Farriery, 2 nd Edition. London: J. A. Allen & Co. Ltd Hildebrand, M. (1965) Symmetrical gaits of horses, Photo Science, Volume 150, pp Humphrey, M. (1995) The horse shoeing book. London: J. A. Allen & Co. Ltd Hunt, W.F., Thomas, V.G. & Stifle, W. (1999) 'Analysis of video-recorded images to determine linear and angular dimensions in the growing horse', Equine Veterinary Journal, Supplement. 31, pp Josseck, H., Zenker, W. & Geyer, H. (1995) Hoof horn abnormalities in Lipizzaner horses and the effect of dietary biotin on macroscopic aspects of hoof horn quality, Equine Veterinary Journal, 27: 3, pp Mark Wood Dip WCF, FdSc. April 2013! Page 41

42 Kane, A.J., Stover, S.M., Gardener, LA., Case, J.T., Johnson, B.I., Read, D.H. & Ardans, A.A. (1996) 'Horseshoe characteristics as possible risk factors for fatal musculoskeletal injury of Thoroughbred racehorses', American Journal of Veterinary Research. 57, pp Keegan, K.G., Wilson, D.J., Wilson, D.A., Barnett, C.D. & Smith, B. (1998) 'Effects of balancing and shoeing of the forelimb feet on kinematic gait analysis in five horses with navicular disease', Equine Veterinary Journal, Supplement. 18, pp Kumar, R. (2010) Research Methodology: A Step-by-Step Guide for Beginners. London: Sage Publications Lanovaz, J. L., Clayton, H. M., Colborne, G.R. & Schamhardt, H.C. (1999) 'Forelimb Kinematics and net joint moments during the swing phase of the trot', Equine Veterinary Journal, Supplement. 30, pp Lanovaz, J. L. & Clayton, H. M. (2001) Sensitivity of forelimb swing phase inverse dynamics to inertial parameter error, Equine Veterinary Journal, Supplement. 33, pp Liljebrink, Y. & Bergh, A. (2010) Goniometry: is it reliable tool to monitor passive joint range of motion in horse s?, Equine Veterinary Journal, 42, Supplement. 38, pp Marlin, D. M. & Nankervis, K. (2002) Equine Exercise Physiology. Oxford: Blackwell Science Muybridge, E. (1887) Animal locomotion: An electro-photographic investigation of consecutive phases of animal movements. University of Pennsylvania, Philadelphia. Reprinted as: (1979) Mybridge's Complete human and animal locomotion - Vol 3. Dover Pulications Inc. mineola, USA. pp Pardoe, C. H., Mcguigan, M.P., Rogers, K.M., Rowe, L. L. & Wilson, A. M. (2001) 'The effect of shoe material on the kinetics and kinematics of foot slip at impact on concrete', Equine Veterinary Journal, Supplement. 33, pp Peham, C., Licia, T., Girtler, D. & Scheidl, M. (1999) Supporting forelimb lameness: clinical judgement vs computerised symmetry measurement, Equine Veterinary Journal, Supplement. 31(5), pp Pilliner, S. & Davis, Z. (1996) Equine Science, Health and Performance. Oxford: Blackwell science Preedy, D. F. & Colborne, G. R. (2001) A method to determine mechanical energy conservation and efficiency in equine gait; a preliminary study, Equine Veterinary Journal, Supplement. 33, pp Rodgers, C. W., Davies, A. S., Pfeiffer, D. U. & Davie, P. S. (1999) Temporal changes in the trot between the first and third horse inspection at a CCI*** 3-day event, Equine Veterinary Journal, Supplement. 30, pp Mark Wood Dip WCF, FdSc. April 2013! Page 42

43 Roepstorff, L., Johnston, C. & Drevemo, S. (1999) 'The effect of shoeing on kinetics and kinematics during the stance phase', Equine Veterinary Journal, Supplement. 30 pp Roepstorff, L., Egenvall, A., Rhodin, M., Bystrom, A., Johnston, C., Van Weeren, P. R. & Weishaupt, M. (2009) 'Kinetics and kinematics of the horse comparing left and right rising trot', Equine Veterinary Journal, Supplement. 41, (3) pp Pollitt, C. C. (1990) An autoradiographic study of equine hoof growth, Equine Veterinary Journal, 22 (5), pp Rose, N. S., Northrop, A. J., Brigden, C. V. & Martin, J. H. (2009) Effects of a stretching regime on length of stride and range of motion in equine trot, The Veterinary Journal, 181. pp Smythe, R, H. (1993) Horse Structure & Movement. London: J. A. Allen & Co. Ltd Staskak, T.S. & Hill, C. (1995) 'Conformation & Movement' In: Horse owners guide to lameness, USA: Williams & Wilkins. pp Stashak, T.S. (2002) 'Trimming and shoeing for balance and soundness' In: Adam's Lameness in Horses. 5th Edition, Philadelphia: Lippincott Williams & Wilkins. Verma, G.K. & Beard, R.M. (1981) What is Educational Research? Perspectives on Techniques of research. Aldershot: Gower Weishaupt, M. A., Wiestner, T., Hogg, H.P., Jordan, P., Auer, J. A. & Barrey, E. (2001) Assessment of gait irregularities in the horse eye vs. gait analysis, Equine Veterinary Journal, Supplement. 33, pp Weishaupt, M. A., Hogg, H. P., Auer, J. A. & Wiestner, T. (2010) Velocity dependent changes of time, force and spatial parameters in warmblood horses walking and trotting on a treadmill, Equine Veterinary Journal, 42, Supplement. 38 pp Willemen, M. A., Savelberg, H. C. C. M., Bruin, G. & Barneveld, A. (1994) 'The effects of toe weights on linear and temporal stride characteristics of standardbred trotters. Veterinary Quarterly 16: pp Willemen, M. A., Jacobs, M. W. H. & Schamhardt, H. C. (1999) 'In vitro transmission and attenuation of impact vibrations in the distal forelimb. Equine Veterinary Journal, Supplement. 30, pp Williams, G. & Deacon, M. (2001) 'Wedges, pads, studs & new materials' In: No Foot No Horse. Kenilworth: Crowood Press. pp Williams, R. B., Harkins, L. S., Hammond, C. J. & Wood, J. L. N. (2012) Racehorse injuries, clinical problems and fatalities recorded on British racecourses and national hunt racing during 1996, 1997 and 1998, Equine Veterinary Journal, Supplement. 33(5), pp Mark Wood Dip WCF, FdSc. April 2013! Page 43

44 Wilson, P.D. Ratzlaff, M.H. Hyde, M.L. & Balch, O.K. (1992) The effects of a compressible plastic shoe, the seattle shoe on the kinematics of the strides of a galloping Thoroughbred horses, Equine Veterinary Journal, Supplement. 12, pp Wilson, A. M. & Pardoe, C. H. (2001) Modification of a force plate system for equine gait analysis on hard road surfaces: a technical note, Equine Veterinary Journal, Supplement. 33, pp Yoshihara, E., Takahashi, T., Otsuka, N., Ishayama, T., Tomiyama, T., Hiraga, A. & Wada, S. (2010) Heel movement in horses: comparison between glued and nailed shoes at different speeds, Equine Veterinary Journal, 42, Supplement. 38, pp Yxklinten, U., Johnston, C., Roepstorff, L. & Drevemo, S. (1998) 'Ollov Original and the Biomechanics in Horses - A Comparative Study Between Horses Shod with Traditional Horseshoes, Rubber Horseshoes and Barefoot', Commercial report, Swedish Agricultural University, Uppsala. Mark Wood Dip WCF, FdSc. April 2013! Page 44

45 Appendices. Appendice 1 Marker placement on the equine left fore hoof capsule Lateral view Mid point of the lateral aspect of the hoof capsule. In line with the hoof pastern axis Mark Wood Dip WCF, FdSc. April 2013! Page 45

46 Appendice 2 Camera placement and calibration. A camera will be set up at a height of 6 cm on a tripod, making the lenses height of 8cm The camera to be 2.5 metres away from the calibration box. Calibration markers measuring 50 cm x 16 cm apart were applied to a box for trotting between. The horse had a number on its shoulder to make it easier when processing the dynamic images and to avoid any confusion. Camera Calibration markers 50 cm x 16 cm apart. Mark Wood Dip WCF, FdSc. April 2013! Page 46

47 Appendice 3 Client Information Letter. Dear Sir/Madam, I am studying at the University of Lancashire for my Bachelor of Science degree in farriery. As part of my degree I am preparing a dissertation which involves performing a clinical study. The study involves comparing the stride pattern between aluminium and steel shoes on show horses. My aim is to identify the most appropriate material for shoeing show horses and the objective is to investigate whether aluminium or steel shoes produce a better stride pattern I would like your permission to use your horse for my study and to fill in some basic information about your horse. All information obtained on this form is kept confidential and no personal details will be used in my study. The data will be kept on a computer which needs a password to access and all information will be deleted once the study is completed. You have the right to withdraw your horse from the study and or any of the information obtained at any time. My contact details are. 2 The Croft, Thwaites, Keighley, West Yorkshire. BD21 4ND. Yours sincerely Mark Wood Dip WCF, FdSc Horse Information Name Height Weight Age Breed Owner name. Owner signature. Mark Wood Dip WCF, FdSc. April 2013! Page 47

48 Appendice 4 Raw data of case studies. Case Aluminium Steel Corn caused by aluminium shoes. Appendix 5 Mark Wood Dip WCF, FdSc. April 2013! Page 48

49 Appendix 6 Hoof marker placement, with aluminium shoe. Appendix 7 Aluminium shoe with groove. Mark Wood Dip WCF, FdSc. April 2013! Page 49