The grey are aka "the hoof" article

The Grey area aka the hoof

            As horse owners, farriers, trainers and vets we all know about the ever increasing foot ailments that horse's endure.  We have all heard the saying, “No foot, No horse”.  Do we really live that approach in our day to day lives with our equine companions?  Have we really obtained all the information possible about our horse's hoof dynamics?  The majority of hoof lameness' and even upper limb lameness' are a mechanical diseases that can benefit from a well developed mechanical solution based on evaluation of the forces at play within the hoof combined with accurate diagnosis and medical therapy. The hoof is often times overlooked as many of the people involved in the care of horses do not have all the information necessary to help maintain a healthy foot.  Farriers have good working knowledge of trimming, nailing, using various tools in there day to day job but many lack knowledge of internal anatomy, radiographic anatomy and physiology.  Veterinarians have a good understanding of anatomy, physiology and diseases but lack many of the hands on skills,  knowledge of external hoof characteristics and techniques that a farrier takes for granted.    The grey area is birthed from neither profession has enough information to communicate on the same level.  As a veterinarian I was not educated on bio-mechanics, how to take farrier friendly radiographs, or how to evaluate lower limb mechanical forces.  There just isn't enough time to completely cover all aspects of the horse while in veterinary school. Most veterinarians base their therapeutic recommendations on findings in veterinary lameness text or based on empirical personal experience and not a well designed mechanical plan based on radiographic findings.  I know this because that was my approach upon graduating veterinary school.  I find in my everyday practice that many hoof care professionals are unaware of a more in depth approach to evaluating and treating hoof disease and lameness.  When we combine the knowledge of both professions with egos aside and develop a plan from that combination more success will arise.  Many foot ailments can be a financial and emotional drain and require aggressive, quick and precise mechanical and medical treatments to be successful.  I have been fortunate to learn from a pioneer in the podiatry world, Dr. Ric Redden of Versailles, Ky.  Through his practical and innovative use of venograms, serial podiatry style radiographs and new mechanical devices, many horses are relieved of unnecessary pain and suffering. 

            Below are four basic guidelines for successfully maintaining healthy hooves and approaching hoof lameness issues. 

1.     

Nutrition- We are all aware that skinny horses do not typically grow good hooves, but did you know that research has shown that added biotin at a rate of 100mg per day will increase hoof quality.  Common hoof supplements that are commercially available only supply 10-20 mg daily. Biotin is long been noted to aid in hair and hoof growth.  All of my hoof cases that have poor quality hoof,  thin soles, slow growth or laminitis (founder) are started on 100 mg of Biotin daily.

2.      Balanced mechanical forces-  This information is obtained from careful and in depth examination of external hoof characteristics combined with information based on measured soft tissue parameters from a farrier friendly radiograph.  Radiographs must be taken in a consistent manner to obtain results that can be compared between radiographs. Radiographic measurements that are important to evaluate are:  Coronary band/Extensor process distance (CE), proximal (top) and distal (bottom) horn lamellar zone (H/L), digital breakover (DB), sole depth (SD), and palmar angle (PA).  Accurate assessment of these parameters will give you an idea if the horse's hoof is within a healthy range  or not.  To be successful in many common foot ailments, such as laminitis, navicular syndrome, caudal heel pain, long toe/low heel and club feet, it is paramount that precise radiographic evaluation of the forces at play is accomplished.  The basis for all my therapeutic recommendations comes from these measurements.  Below is a diagram of soft tissue parameters commonly utilized.      

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            Farriers are often given a very vague prescription such as wedge the heels and back the toe up, but how much wedge and where should the toe be backed up to.  A more precise prescription might include:  DB at 0 mm, PA increased from 0 degrees to 10 degrees and use of aluminum rail shoe rockered mid shoe attached with glue and fit with a positive pressure frog plate.  In order for a prescription like this to be given and received both farrier and veterinarian must speak and understand the same language, which also means that both individuals have pursued a higher level of understanding of the equine hoof. 

3.      Preventive hoof care programs-  Many equine hoof ailments are results of long standing minor mechanical imbalances and predisposing genetic traits. Many of these can be identified early in life and monitored on annual basis via farrier friendly radiographs.  For example, if your horse as a yearling has long pasterns, zero degree pa and a 30 mm breakover then you can assume that as an adult he will be predisposed to crushing his heels, maybe have thin walls and sole.  However since it has been identified at an early age a maintenance program for the farrier can be developed that may differ from a basic perimeter fit steel shoe or traditional trimming. Many horses these days are not blessed with perfect feet and many would benefit from minor modifications in shoeing approach early in life to help delay or prevent the onset of hoof disease.  A preventive hoof care program should involve a yearly podiatry style exam with radiographs that could be easily included into your yearly vaccination and wellness exam.   Foals should be evaluated within the first week of life and every month for the first year of life.  Radiographs can be taken any time along the way but definitely prior to entering training as to develop a hoof care plan.  We as hoof care professionals need to be focused on maintaining hoof mass and quality instead of pretty and appealing to the eye.   We can find minor changes in the measured soft tissue  parameters long before bone changes occur and before the horse will exhibit pain or discomfort. 

4.      Regular and consistent farrier visits-  It is very important to have shoeing/trimming intervals that are appropriate for the  individual horse as mechanical properties and soft tissue parameters change early in the shoeing interval.  Often times by the end of the shoeing period, especially if overdue, the soft tissue measurements such as palmar angle and digital breakover have entered into an unhealthy zone.  Using the podiatry style radiograph to design a healthy protocol that may maintain a healthier palmar angle and digital breakover longer in the shoeing cycle is another added benefit for preventive hoof care programs.

           

            In conclusion, I would like to see veterinarians and farriers alike adopt this similar language and radiographic techniques to evaluate the equine hoof. Without regard to consistent technique and  a detailed evaluation of the mechanical formula there is an inherent risk of not obtaining the level of success that one may desire.   What we do, and more importantly what we do not do to the hoof, not only has an affect today but in the future as well.  We all need to recognize that a perimeter fit flat steel shoe may not be the best option for every horse, as simple modifications may prolong the health of the foot and prevent problems down the road. 

Further reading and resources: 

1.      Dr. Redden's website, www.nanric.com, numerous articles regarding evaluation and treatment of many common foot ailments and soft tissue parameter measurement illustrations and articles.

2.      My website and blog, www.innovativequinepodiatry.com and www.innovativeequinepodiatry.blogspot.com

Upcoming Clinic with Dr. Ric Redden

Come join us for a unique learning opportunity!  Hope to see you there.  If I can answer any questions regarding this lecture/demo please feel free to call 918.235.1529 or email at iepvs11@gmail.com

Backyard mare Project, Updated radiographs after returning to Flat perimeter fit shoes. Please look back at previous Post for serial podiatry style radiographs and venograms

Hello again, I hope this finds you and yours healthy and safe.  Kellee and I have been very busy and enjoying meeting many new clients and horses.   We are now focused on getting ready for Dr. Reddens In depth podiatry clinic in October and hope to see many of you there.  For more information on that go to our website at www.innovativeequinepodiatry.com and click on the Nanric link. 

I am posting some radiographs of Susie Q which is my old faithful trail horse that I have placed back into to a more traditional perimeter fit steel shoe after being in a rockered four point shoe and obtaining 19mm of sole depth.  Please look back at the other post that contain the previous radiographs and venograms.  I will post below radiographs from June 20 when the steel flat perimeter fit shoes where applied and today's radiographs.  A good ole 8 week cycle.  She did lose one shoe at 2 weeks in and I replaced.  Note the toe clip on the Left front.  Notice the loss of sole depth in both fronts and gain of nearly 10 mm of digital breakover.  She did grow hoof wall which elevates digit from the shoe but true dense sole depth, measured from the tip of the coffin bone to the noticeable dense sole, is diminished by a few millimeters. 


You would expect an 8 week cycle to have a ton of sole depth but this is where we are wrong many times.  If you take these hooves and reset while cleaning and cupping the sole you may have as little as 10 mm of sole when finished.  If this horse remains in this similar package another 8 weeks and we are lucky and maintain that 10mm of sole we are still below the healthy sole depth of 15 mm required to have a healthy vascular supply and protection noted on the venograms.   Digital breakover has increased almost 10mm.  This had increased the effective lever arm to a whopping 15-20mm past what would be considered ideal of 20-25mm.  The shorter breakover and self adjusting palmar angle is what allowed this mare to obtain better than adequate sole depth of 19mm.

Also notice the decrease in Palmar angle.  This is the reaction to the lengthening digital breakover and the base of support migrating forward allowing more load and crush to the palmar aspect of the hoof. This will overload the digital cushion and deep digital flexor tendon and overwhelm it's capability to suspend the coffin bone at a higher palmar angle.  I believe the deep digital flexor muscle continues to get stretched and has difficulty returning to home base with maximum contraction capability and cannot pull the palmar angle back up to a more positive angle.  The long digital breakover is antagonizing the ability for the flexor muscle be an affective suspension apparatus and hold the better palmar angle.  At the same time with extra antagonism against the flexor tendon we are adding additional compression of the solar corium below the tip of the coffin bone which in turn compresses the blood supply and reduces production of horny sole and the measurable distance from the tip of coffin bone to the cup of the foot which is the black air space between sole and shoe.  It is this response that suggest to me that many horses should not be maintained in traditional perimeter fit shoes but in a package that will at least maintain a better digital breakover longer in the cycle.  This approach obtained through natural balance shoes, mustad equilibrium, kerkhart comforts, four point shoe, or by simply forging a roll in the toe of a plain steel shoe, will allow better maintanence of sole depth, tendon tension, palmar angle and overall health of the entire limb.

 Reducing these forces should also reduce hyperextension forces in fetlock and carpus (fetlock and knee) and may help in reducing arthritic conditions in aged performance horses if started and maintained in this manner early in life.  Podiatry style radiographs early in life will help determine which horses may benefit from shorter digital breakover shoes and aid in maintaining better hoof  and limb health.  Many times shortened digital breakover is only part of the equation to institute better blood supply and foot mass recovery.  I suggest the above as a bare minimum for maintaining a sound horse.  If we are not obtaining the goals we set forth, we must also consider palmar angle adjustment especially in unsound horses with diagnosed lameness issues.  Susie Q is not lame but is beginning to stumble with this long breakover.  I can only surmise that if I where to continue the flat shoeing approach coupled with a performance career for several years that this will lead to certain pain and inflammation in many possible areas. 

I plan to reset the flat steel shoes and continue to monitor over the next 4-6 weeks. 

This is first flat shoe after rocker

8 Weeks in flat shoe, note loss of sole depth and increased digital breakover.

First flat shoe after rockers

8 weeks in flat shoe, note loss of sole depth and very lengthening of digital breakover and loss of palmar angle.