HOOF MAPPING Hoof mapping is a reliable and useful tool to recognise the location of internal anatomy from external references & asses hoof balance / hoof health. Whether you are applying a successful barefoot trim or looking for the optimal placement of a shoe / prosthetic, the principles of hoof mapping provide the foundation of my hoof-care. It is vital time is taken to get the hoof balanced to the internal anatomy and hoof distortions are recognized in their earliest form. The most expensive shoe systems will be of no benefit if they are not fitted in relation to the internal anatomy. Image showing overgrown hoof capsule in need of a trim the hoof is mapped and pinned ready for radiographs Note: o Length of central sulcus = shock absorbing zone of foot. The digital cushion and lateral cartilages reside above here. This zone is responsible for good blood flow and circulatution, absorbing concussion, proprioception adding in the coordination of the horse and aligning the bony column within the foot. o True apex of frog = this is the location the deep digital flexor tendon attaches to the coffin bone o Widest part of foot = centre of rotation of coffin joint o Optimal placement of breakover = 0.25inch ahead of tip of the pedal bone. Toe in photo is too long and has migrated forward of its optimal point of break over which would ideally be placed at the location of the drawing pin placed in the sole The soft tissues holding a healthy coffin joint in place will need to be free of undue stress. Structures that take on more stress than was intended will begin to develop a fail factor. A well balanced foot will have as much distance ahead of the widest part of the foot (the centre of rotation of the coffin joint) as there is in the back. This allows the joint to function free from undue leverage. This will also utilize the shock absorbing zone with in the foot and allow the horse to move freely over the toe at time of break over. Horse owners can use hoof mapping to asses hoof balance Hoof mapping can be used by horse owners to asses hoof balance. Simply establishing a rough guide to the widest part of the foot and evaluating the ratios. If there is more foot in front of the widest part of the foot than behind your horse has hoof distortion and your horses hoof capsule is losing its relationship to the internal anatomy! Common gait faults associated with hoof imbalance are tripping stumbling forging overreaching brushing etc. HOOF MAPPING PROTOCOL Finding the dimple or the last weight bearing surface of the foot 1. The Heels (Mark the Dimple in the Back of the Frog to Assess Heel Position relative to the Back of the Foot) o the central sulcus forms a” V” in its most caudal location. highlight this with your marker o using your fingers you will feel a flat spot just off the back of the frog butress draw a line across o Push the tip of the marker into the” V “ that forms in the central sulcus all 3 markers should now line up along the same tangent this is or should be the last weight bearing surface of the foot o Note the position of the heels to the position of the lines you have just drawn if there is a distance greater than ¼ inches then your horse has heel distortion if one heel is further forward than the other there is also medial lateral imbalance. 2. Recognize the Distortions of: (Note any distortions or non-distortions you see!) The Frog (is it Narrow, Long & Stretched, Diseased, etc.) The Bars (Excessive Curve, Laid Over, etc.) The Toe (Pointed on Front Foot, Seems Long, etc.) 3. Exfoliate the: (farriers job) Frog o Identify the True Apex. o Only loose tags. o Clean Central Sulcus o Trim corners so they don’t interfere with the rasp when trimming the heels Sole – Chalky Material o Quarters (Extremely Important!!) o Heels (Seat of Corn or ‘V’ between hoof wall and bars) o Pillars or Toe Quarters (Be very specific as this is your primary M/L Balancing Structure) o Across the Toe or Top of Sole Callus (if barefoot trim be conservative) Bars – Fractures, Excessive Curves, Laid Over, Bacteria Traps, Etc. The functional sole will secrete a waxy material. It's been shown by Mike Savoldi that the thickness of the functional sole is equal under the ventral border of the distal phalanx. Therefore, trimming each side of the hoof wall the same distance from the exfoliated, functional sole will insure that lateral/medial balance is easily attained. It should be noted however, that you must be very specific about accurately identifying the live, functional sole in order to use it as a guide. If you cut into the sole too aggressively and go through the plane of the live sole/dead sole junction, you will jeopardize your ability to use the sole as a guide. So, tread lightly. The live or functional sole is seen as the waxy appearing surface just below the chalky or exfoliating sole material. If you identify the live sole in the region close to the wall/sole junction, then trim the hoof wall an equal height from that live sole on each side, you have the best opportunity to get the ventral border of the distal phalanx parallel to the ground from side to side. Whether you leave ¼”, 1/8” or NO wall above the level of the sole, balance is achieved as long as you leave the same amount on the opposite side. This method is extremely helpful and much more accurate on those horses that are pigeon-toed or base narrow, because the hoof capsule can be shifted and lose its visual relationship to the coffin bone, and consequently becomes unreliable when sighting in a more conventional way. In short, the live sole is proving to be a much more reliable and less subjective means of evaluating and achieving medial/lateral balance. This waxy material will be of equal thickness either side of the pedal bone. Be very precise to identify this structure but do not remove it. This is your primary tool to achieve medial lateral balance. 4. Finding the centre of rotation of the coffin joint Mark the: True Apex of the Frog Widest Part of the Foot (Use all 3 Methods to locate) o From the True Apex of the frog, measure back (rearward) about 1” (on a size #0 to #2 foot) and draw a line. This is generally the widest part of the foot. o Find the position where the bars terminate into the frog commissures. If you run a hoof pick up the commissures (from the back forward), you will find a raised hump which general indicates the termination of the bars. A line across the foot at that position generally represents the widest part of the foot. o Mark an arc about 2” long in the quarters at the sole/wall junction on both sides of the foot. You should be able to visually see the peak of the arc on each side of the foot. This is the widest part of the sole. o All 3 marks should line up! Draw a line to connect them together. (if 2 line up and 1 is miss placed then use the 2 marks that do as the widest part of foot) 5. Optimal placement of break-over The Approximate Tip of the pedal Bone [PIII] is about 1.75” ahead of the Widest Part of the Foot on average sized feet. Approximate the Point of Breakover (Before & After trim) Area of the Pillar at the Sole Level Draw Line at Sole Callus/Wall Junction Around Toe (from Toe-Quarter to ToeQuarter) If possible, Draw a Line Across the Inside, Top Edge of the Sole Callus o Normally this is about ¼” ahead of the tip of the coffin bone, or 2” ahead of the Widest Part of the Foot on a medium sized foot. This should be your projected or estimated point of breakover. 6. Evaluate the Ratios: (Illustrate where current heel & breakover is, as well as where you hope to get them!) From the Widest Part of the Foot to the Rear Most Weight Bearing Structure (Before/Current & then for the After/Goal mark, use the Frog Buttress) From the Widest Part of the Foot to the Point of Breakover (Before/Current & After/Goal) Attainable Goals? – 50/50 Ratio or Slightly More to the Back 60/40 There is now an equal amount of foot behind the widest part of the foot as there is in front. This is illustrated in this picture using the width of the rasp. The frog is in contact with the ground and therefore becomes the most caudal weight bearing structure and the bevelled toe results in breakover point in a more caudal location. The toe of the foot has a natural roll worked into the foot at the location of optimal break-over & the hoof capsule is in a good alignment with the pastern Long toe low heel in a broken back hoof pastern alignment Note frog apex is stretched and pointed heels terminate way forward of the back of the frog as a result the distance in the back of the foot is shorter than the distance in front The bars are laid over and curved and as a result they are offering no support to the lateral cartilage The toe is stretched This type of foot is often miss-red! Because the foot is in a broken back hoof pastern alignment we are asked to trim the toe and leave the heel in an effort to stand the horse up However there are massive distortions in the back of this horse’s foot!! How can leaving the heel be a good thing for this foot? When the foot is exfoliated the bars are trimmed to straighten out the collapsed bars and a corn is uncovered due to the pressure of the heel in its current position the heel is trimmed to the back of the frog an increase in the distance from the widest part of the foot is achieved (utilizing the shock absorbing zone ) the loading point of the heel is placed in a caudal position away from the area of the corn The frog is now in contact with the ground helping to align the bone column and adding in the blood circulation to the foot & proprioception A more appropriate position for break-over can be achieved with the position of the shoe When the dorsal hoof wall is dressed despite trimming the heel the hoof and pastern are in a better alignment!!! The same basic principles described here are used when trimming horses for shoes! And in many cases trimming distortions out of feet is all that is required to maintain soundness and keep horses performing to the best of their ability. So should my horse be Barefoot? A Barefoot lifestyle is for many horses a healthy option! I believe many horses are shod unnecessarily and from a biomechanical stand point (if structures of the foot are non distorted & healthy) foot function is in its most natural state! I encourage many of you to consider removing shoes if your horse fits certain criteria. However there are many factors that must be employed in order for it to be a successful venture, Some primary components from the owner or care taker are: environment, husbandry, hoof health and expectations. The farrier or hoof care provider will have three primary goals for successful barefoot trimming: Protection, Support & Balance. ENVIROMENT / HUSBANDRY One of the first things that needs to be addressed and understood, especially by the horse owner or caretaker is the commitment that is required by them to have a horse go without shoes and still do the type of riding that is expected of them. You are asking your horse to” be natural” and then asking something unnatural of them. It takes extra time for conditioning the feet, as well as an awareness of both the living and riding terrains that the horse will encounter in order for the horse to stay sound and comfortable. The horses hoof is a complex structure with clearly defined functions the most relevant is its ability to absorb concussion. This vital function is reliant on the maintance it receives good nutrition and correct fluid levels. (12-15% being seen as optimal) the introduction of extreme environmental factors can result in even the strongest feet starting to suffer. In the depths of winter or even wet summers. We place our equine friends in water logged fields (even heavy dues in the grass) for prolonged periods of time. So that they can benefit from some turn out! However this can have a negative effect on the hoof capsule. Equines with weaker feet are most at risk. The sole can become spongy. It may flex under thumb pressure and as a result offers little protection to the tip of the pedal bone. The sole is easily penetrated by sharp objects such as grit or flint increasing the risk of abscessing & once the sole loses its strength the hoof capsule becomes vulnerable to the shearing forces of locomotion. The hoof wall and its attachment to the pedal bone via the laminea are torn with every foot step, we call this mud founder it is a type of laminitis. Special care should be given to horses in Breeds with genetically weaker feet such as thoroughbreds. These Equines with weaker feet will need a very different stable management regime involving much more time in a dry environment if they have any chance of having a healthy hoof capsule. (Shod or barefoot) Products that can help in conditioning feet Products such as keratex hoof gel can help. As this product will if used regularly will build a hydro repellent layer and waterproof the hoof capsule it should be applied when feet are dry and the product should be allowed to dry. Keratex Hoof Gel allows the hoof to breathe. Air can pass freely through Keratex Hoof Gel in either direction and excess moisture can be expelled from the hoof. No water or typical chemicals can enter the hoof from the outside. In dry conditions when there is no moisture in the ground, Keratex hoof hardener is a great product to use as it works with the keratin in the foot and helps to make it more tear resistant. Keratex Hoof Hardener strengthens weak, worn and cracked hooves by improving the molecular structure of the horn itself. This results in a reduction of bruised soles & abscesses. EXPECTATIONS The owner’s expectations also play a part in whether barefoot is a good option for their horse or not. For example, it is unreasonable to expect that you can keep your horse in a Stable or small paddock with soft ground or deep bedding for 24 hours a day and then take him for a ride on firm or even stony tracks a few times a week. If the equine has been placed in a wet or soft environment the hoof capsule will become soft. Feet will wear at a faster rate on abrasive surfaces if soft. The whole foot needs a certain amount of time to adapt and adjust to the difference in conditions. If that same horse was only ridden in a soft arena or something like that, then he would probably do fine. If you expect your horse to be ridden on firm stony ground its living environment must be dry so feet can harden and the environment must be similar to what you expect to ride them on. If the animal is not comfortable roaming freely it will not be comfortable under saddle. HOOF HEALTH The quality of both the external and internal hoof components can also be a limiting factor in horses going barefoot successfully. There are certain breeds that do have feet that are better suited for a barefoot lifestyle. Horses with thick walls and thick soles will obviously be better able to adapt. If you go through the proper process in transitioning from shoes to barefoot, if horse has kept in a dry environment and owners have put in the time to condition the feet, but the horse is still uncomfortable even on a medium type terrain, then I feel it is inhumane to continue to subject the horse to that situation. THE HOOF CARE PROVIDER PROTECTION When we talk about protection, we are basically addressing the protection of the coffin bone inside of the hoof capsule. In general, the structures that are responsible for protecting the coffin bone are the sole and the hoof wall. From a trimming standpoint, these are also the two structures that are often addressed differently from one environment to another. Meaning, that in certain climates, more sole and/or wall protection is necessary than it would be in a different region. The success or failure of implementing the guidelines is largely determined by the choices you make when it comes to exfoliating the sole and then trimming the wall with respect to that sole. Obviously you could opted to take the ultra conservative approach regardless of the environment, and never remove any sole material in the toe region and leave ¼” of wall clearance above the sole. In the majority of your cases, you would probably not have sore horse’s .However, in most environments you will eventually end up with massive distortions and imbalances because neither you nor the environment is facilitating the real maintenance needs of the foot. Therefore, it is up to the hoof care provider to figure out where that protection / equilibrium is for each horse in their care. 1. First of all, you must be able to recognize what you are starting with. This means that you should always run hoof testers over the sole prior to starting your exfoliation. In doing so, you will not only get an idea of any sensitivity to sole contact that the horse may have, but you will also gain an appreciation for the density or texture of the sole material. 2. It is important to recognize how much length of wall (beyond the level of the sole) that you have before you start trimming. In the hard environments after long periods of dry weather the ground will not yield to the foot. Therefore, if the horse has a moderate amount of room to roam, the hoof wall is often worn down to the level of the sole in the toe region. In light of that fact, most horses require very little sole exfoliation in the front half of the foot. Even the slightest amount of sole removal in feet like this can be disastrous because there is no wall available to take over the role of protection once any amount of sole is removed. The same is true in an extremely wet environment where feet can get flared out and the sole sinks to the same level as the wall. In these cases, you will need to remove the cracked and flared hoof wall, however in doing so you will virtually have a negative or zero sole/wall clearance. If you then remove any sole material at that time, the horse is likely to be off, and in many cases suffer from what you’ve done. The point is that if you do not have any protective wall material before you begin your trim, it may limit the amount of sole material (if any) that you can safely remove, even if it is chalky material. 3. Sole thickness and sole depth. Although these terms are often used in conjunction with each other, the depth of the sole and the thickness of the sole are not the same thing. Sole thickness is the amount of live or functional sole material that is generated from the sole corium. In layman’s terms, the sole thickness is usually recognized as the amount of functional sole material beneath the coffin bone. The best way to determine the amount of sole thickness a foot has is best measured with the use radiographs. As it is not always easy to know exactly how much sole thickness exists just from looking at a given foot. A good sole thickness could be as much as ¾” (22 mm); where as poor sole thickness could be as little as ¼” (6mm). The more live sole thickness a horse has, the better chance they have of being comfortable barefoot (at least in theory). Horse with good sole thickness horse with very little sole thickness It is no surprise. Horses with very little sole thickness will often have a tougher time going barefoot. The depth of sole is better described as the amount of sole build-up above the level of the true frog apex. The build-up of material can be live and functional, but in many cases it represents an excess of exfoliating sole tissue that can be removed. In most cases, too much depth of sole or a retained sole can contribute to pathologies. Therefore, learning to recognize how much depth of sole you have is necessary in order to make appropriate decisions about the protective needs of the foot. Locating the true frog apex is the key to determining the depth of sole. Providing protection to the coffin bone is certainly a balancing act. If you take too much from one area, you have to make sure you have (or leave) enough from the other area to keep the horse happy. SUPPORT As always, it is important to evaluate the structures that are involved in providing support to the barefoot horse. Once again, the coffin bone (and therefore the bone column) is the structure we are trying to offer support to. The components of the foot that facilitate this support are: the frog, bars, sole, and hoof wall. The hoof wall holds the coffin bone in place through its attachment via the lamina . The sole (primarily the pillars & sole callus) also help hold the coffin bone up inside the hoof capsule The bars help to support and hold the lateral cartilages up, which in turn support the back of the coffin bone. The frog acts as a primary support structure by influencing the soft tissue in the back of the foot (like the digital cushion) to hold the Navicular bone in place and lift the back of the coffin bone through the lateral cartilage matrix. Like the goal of Protection, there is a balance between all the primary support structures of the foot. If the hoof wall fails (like an under run heel for example), and the bars fail (by curling and lying over), then the frog has to pick up the slack if the foot is going to remain functional. It is apparent that the support structures of the foot work together as best as they can to get the job done. However, when 1 or more fail, the other structures have to take over and unfortunately, in time, in some cases, they too begin to fail. From a barefoot management standpoint, when all the support structures are healthy and functioning properly, the likelihood of the horse being comfortable and striving in a barefoot condition is much more likely. If hoof health is suffering, then whatever means that are necessary to help restore function to the foot should be employed. Many times, a good shoeing program that jump-starts the restoration process is often helpful for yielding the best barefoot management results in the long run. BALANCE When we talk about balance, we are really talking about equilibrium to the coffin joint (and joints above) both statically and dynamically (meaning at rest and in motion). As we look at the majority of improvements made in the barefoot care of horses over the last 15 years, the biggest improvement in terms of balance is the reduction of leverage. Leverage effects the foot from a dorsal/palmer (front to back) and a medial/lateral (side to side) standpoint. By simply dividing the ground surface mass in equal proportions around the centre of articulation of the DIP joint (basically the widest part of the foot), you will minimize the majority of excessive leverage forces on the internal structures of the foot. At the same time, if you prepare the hoof wall at an equal height from the functional sole on both sides of the foot, you will effectively equalize the balance of the coffin joint from side to side (since the sole is uniform in thickness on each side of the coffin bone). To sum up, the entire package (Protection, Support, Balance, environment, husbandry, hoof health and expectations.) Need to be employed in order to have a shot at achieving SUCCESS with barefoot horses!