Refurbishing Poor Quality Feet
1996 - 10th Annual Bluegrass Laminitis Symposium Notes
Refurbishing Poor Quality Feet
Written and presented January 1996 by R.F. (Ric) Redden, DVM
The first step for successful foot refurbishing is goal setting. All parties involved have either a negative or positive influence on the end result. Discuss in detail the desired image, use of the animal, and set short term realistic goals from one shoeing to the next. If these goals are not met, regroup and clarify the problem.
Positive results are the product of good planning and the execution of skills. I must agree with Dr. Doug Butler that "the power of observation is our most valuable tool", and skill is meaningless without it. There are basically two schools of thought for refurbishing poor quality feet.
1. Quick Fix: I refer to as "The Band-Aid Technique", offers immediate cosmetic appeal and often results in a favorable response which is relative to the condition in which you started.
I often hear "You should have seen this foot when it came to us", and I have been guilty of saying the same. Evaluating the craftsmanship of any shoeing job immediately following shoeing has many pitfalls. Most all pathological conditions related to mass and balance steadily deteriorate over the next few weeks. Evaluating a job at the end of a given shoeing period often leads one to believe the job performed was performed incorrectly, a very unfair assessment.
For years I asked myself, why does the quality of the horn often deteriorate, in spite of consistent, regular good shoeing? Being critical of my work, I developed a simple observation plan with each follow up case. Is the foot better, the same, or worse than it was following the last shoeing? Failing to meet the requirements of load, balance, mass and function invariably results in loss of form and produces undesirable side effects. Quick fixes certainly have their place in our profession but we must remember, payback can be devastating. You can pinch hit and quick fix on a weekly basis and squeeze a few more miles out of a foot, but when you have exhausted the Band-Aid option in the peak of the season, you have but one option, shut down. Careers are shattered and millions lost annually from sore, unresponsive feet. How can we avoid the risk associated with the quick fix?
2. Natural sculpturing is a method that offers consistent favorable results on a daily basis. This method relies on the natural load sensors of the foot that apparently transmits a strong message to the growth center. Once properly stimulated, strong horn mass quickly replaces weak, thin, dysfunctional horn. This method is best referred to as "Sculpturing for Tomorrow". Cosmetic appeal can be maintained as well as desired foot flight with this method. It is the natural consistent replacement of horn mass that verifies that there are no true poor quality feet. All feet will respond, some quicker than others, and the response is good for the first stage (five to ten days). When examining a case I like to start by assessing the current trimming or shoeing method. Sort out all the good and bad points. Observe the physical condition of horn and identify all areas that appear to be weaker as the shoeing period progresses. Even though we may not have answers that would withstand the challenge of scientific studies, we can eliminate most all aspects of the shoe or trim in order to assure a favorable response.
I prefer the philosophy of leaving every bit of the horn the horse needs and taking only what it does not need. With this concept, the actual work is cut in half and the thought process doubled. Relying on keen observation to guide the knife and rasp offers a consistent chance for natural recovery. Horn, mass and balance steadily improves throughout the shoeing or trim period and favorable results are quite evident four to six weeks later. This approach allows us to develop a new mindset for basic requirements.
There are three basic problems that consistently create poor quality feet:
1. Excessive Breakover: Anything that lies anterior to a perpendicular line, 1" to 1 1/4" in front of the point of the frog.
2. Bent Heel Tubules: Loading the heel tubules on their side has serious side effects.
3. Excess Moisture: Capsular horn is rigid and durable when the water content is quite low and becomes very weak and unresponsive when water saturated.
Basic Principles of Restoration
Support the horn tubules at the posterior pillars. Rasp the heels back (from the point of the frog back), until the bent tubules are straighter. This will be at the widest point of the frog. Using this technique, it is quite easy to increase the support surface of the hoof 1" to 2". I prefer the term "push back" verses "lower the heel", as many trainers become confused when they think you are lowering the heel on a horse that seems to have no heel. Simply put, if you want a heel to be strong and durable, the tubules must be loaded in a manner that enhances pillar function.
Determine the depth of sole without taking any of it out. Trim a small area around the apex, down to the frog-sole junction. This is a helpful technique when soles are quite thick and hard. At this stage, it is time to determine whether to apply the four point shoe or go straight to the four point barefoot trim. Several factors must be considered at this stage. The principles of load and breakover will basically be the same with or without the shoe. Performance horses that have reached the limits of quick fix and are forced into a short rehabilitation period will need to be shod because the rehabilitation period is too short to fully utilize the effects of the four point trim. High profile stallions, mares and show animals, that have to frequently meet the public eye approval, will need temporary shoeing as well, to avoid unacceptable tender feet. Those with extremely thin soles and minimal mass will need shoes for a short while as well.
The four point shoe offers reasonably quick results, protects the sensitive sole and can be adapted to all breeds. The shoe, regardless of breed, is designed in such a fashion that breakover is 3/4" to 1" anterior to the apex of the frog. Covering the horn tubules to the widest point of the frog, the 4-point shoe enhances medial-lateral breakover, reduces stress on the nails and consequently weak walls.
The open heel offers a more natural dynamic heel action, especially when used in conjunction with arch support. The breakover properties of the shoe allow the farrier to use a very small nail, reducing further damage to the walls. I prefer aluminum, as it is very light, 1/8" drilled holes to accommodate a 1 1/2" race nail is sufficient for most all feet, regardless of size. The drilled hole offers minimum wear, optimum pitch and placement. Nails that seat super tight, cause little or no damage to the horn and do not create excessive hole wear.
Once the feet are shod, the horn must be kept at a very low water content. Stiff horn apparently picks up a specific signal and transmits a positive message to the growth centers. Water soaked horn will collapse under load and has little or no recall. I prefer Keratex Hoof Hardener as an aid to creating consistent tough, rigid horn. Hot seating is helpful in the early stages of breakdown but seems to cause excessive drying when the horn wall is open with multiple fissures and cracks.
Four point shoeing stimulates horn growth, making it essential to reset every three weeks for the first few shoeings.
Breakover will migrate forward 3/4" to 1" in three weeks, requiring frequent touch ups to maintain the new response. The downside of the four point shoe over the four point trim appears to be relative to natural signals to the pillars. The shoe invariably traps moisture, bacteria and debris and interferes with natural ground horn stimuli.
The typical poor quality hoof, whether still on the circuit or retired for breeding purposes, has a typical appearance. The ground contact at the heels is 3/4" to 2" forward, at the widest point of the frog. Breakover is 2" to 3" forward of the apex. The bars are basically nonexistent and the heels are folded under and forward. The clinches are raised and wall texture is like swiss cheese. All these dysfunctional areas are apparently due to the result of improper pillar loading, horn growth and maturation. All can be corrected over a period of four to six months.
Attempting to refurbish extremely poor quality feet for several years has led me to question the validity of the eggbars and extremely full shoeing at the quarters. It is apparent to me that eggbars are great support for the suspensory apparatus of the limb but they do not support the heels. Close observation will reveal increased bending of the tubules the longer the eggbar extends out the back. The horse may appear sounder and look great when freshly shod but has the same deplorable heels within six weeks. (All bars appear to prohibit natural action of the frog, sulci and bars which play a major role in reconstruction.) It has been said "That eggbars distribute load". Sounds good, but what do they tell the load sensors when the horn tubules touch the shoe 2" to 3" forward of its most posterior border of the bar? It is apparent from the wear on the shoe, as well as the frayed nature of the horn tubules, that a serious force is concentrated over a small area of the shoe. The bar is often embedded in the base of the frog, which indicates a lack of support. When wedges are used with eggbars, the tubules often become even more bent.
Very full shoeing seldom improves horn mass and quality, leading me to question the validity of increasing the medial-lateral breakover which adds additional stress to the horn wall, clinches and lamellar attachment.
Rocker toed eggbars - Do they continue improving the foot with each reset? The location of the rocker in relation to the point of rotation is very important. Most poor quality feet cannot be fitted with a rocker toe shoe, placed at the point of rotation, as mass is at a minimum and there is not adequate sole or horn. Placing it well in front of the dynamic breakover is helpful, certainly over that of a flat shoe, but it fails to stimulate continual restoration of mass.
Arch support appears to play a major role with natural reconstruction. Mud and debris that packs tightly into the sulci must surely play a major role in hoof health. Ground surface contact along the angle, sole, bars, sulci and frog offer a tremendous uplift that apparently enhances heel function and reduces stress to the wall and sensitive attachment. Placing a bar across the area, regardless of reason, appears to interfere with heel function and preludes maximum mass development. Placing a bar across the heels appears to reduce the possibility of uplift support.
Included are a few diagrams of the shoes I use with most all reconstruction. This basic shoe has many adaptations that can meet the demand of most all breeds. I hope you find it to be as valuable a tool as I have.