Jillian Mills, DVM, DACVSMR, CERP, CVA, Starwood Equine Veterinary Services – Courtesy of AAEP
Question: What are your thoughts on barefoot trimming for horses with moderate navicular disease?
Answer: Navicular disease is a syndrome affecting not just the navicular bone itself, but the entire podotrochlear apparatus located in the heel of the foot. Advanced imaging modalities, such as MRI, have allowed us to determine the specific structures that are injured when a horse is experiencing heel pain. The more specific the diagnosis, the better your veterinarian can direct their treatment and shoeing recommendations.
In general, there are two things we would like to accomplish when shoeing a horse with heel pain. These principles include reducing extension of the coffin joint, and decreasing the peak pressure on the navicular bone by unloading the deep digital flexor tendon (DDFT). With farriery you are able to provide pain relief by applying both static and dynamic shoeing principles. An example of a static shoeing principle for heel pain would be the use of a wedge pad to raise the heel and unload the DDFT. In this scenario, a wedge pad changes the biomechanics of the foot at all times, even while at rest. With navicular disease, permanent heel elevation can sometimes be detrimental as it can induce contraction of the DDFT. Barefoot trimming would require you to implement similar static shoeing principles, with the goal of heel elevation and improving breakover at the toe and quarters.
Therapeutic farriery also emphasizes the use of shoeing principles that have a dynamic effect. In the case of dynamic shoeing, the biomechanical effect only occurs in deformable footing. At rest, the biomechanics of the foot are unchanged. An example of a dynamic shoeing principle for heel pain would be the use of a flat reverse shoe. A reverse shoe prevents the heel from sinking while the horse is being worked, unloading the DDFT. The absence of a bar at the toe also encourages the toe to sink and allows the horse to wear its toe, maintaining ease of breakover throughout its shoeing cycle.
Both static and dynamic shoeing principles have their place in certain scenarios and for specific injuries. In the case of navicular disease, barefoot trimming requires you to apply static shoeing principles and may not be as beneficial as utilizing a dynamic therapeutic shoeing principle for the management of heel pain.
Question: As I watch my horse walk towards me, I can see that the outside of her left front foot lands first then the inside. She also has a lot of arthritis in her left fetlock area. Can my farrier do anything to make her front feet more balanced?
Answer: Uneven hoof placement does not necessarily mean that your horse’s feet are unbalanced. Foot fall can also be significantly affected by conformation. The two main means for evaluating medial-to-lateral (inside-to-outside) hoof imbalance include hoof measurements and radiographic evaluation. Radiographs (x-rays) are beneficial because they can make subtle imbalances more obvious and identify other abnormalities that may also require correction, such as a negative palmar angle. A radiographic shoeing consultation will allow your veterinarian and farrier to collaborate on what is best for your horse’s specific ailment.
Abnormal foot fall, regardless of the cause, can result in asymmetric joint loading. Abnormal joint loading has been implicated in the progression of osteoarthritis. Your farrier could apply a shoe with a heavily beveled medial (inside) quarter and branch to aid in medial breakover. This will reduce the strain on the lateral (outside) tendons and ligaments of the limb. To further reduce the concussive forces on the inside sole and limb, the width of the outside branch of the shoe should be widened to aid in redistributing the load.
Question: After years of lameness issues and treatments that had limited results, I decided to remove the shoes off my then 14-year-old Warmblood mare. She has been barefoot since 2016 and had an excellent farrier that was doing the Bowkers trim. Things progressed positively and have just recently started her back to very light work. The farrier that I had been using moved and another has taken over the trim. Before starting her back to work she was on a 5-week schedule and her feet looked great, no longer crushing heels and landing flat instead of toe first. She remains on the 5-week schedule, but the hoof is flaring and by the start of the second week, becomes really flared and not the nice hoof shape I had before. The foot is widening and I feel she is crushing heels again. She is a big girl and I expect changes but concerned this could be heading in the wrong direction. My current farrier is also concerned as he now must come every three weeks instead of five. I consulted my veterinarian and thought X-rays would help determine if on track. Any suggestions?
Answer: It sounds like both you and your farrier are concerned with the recent change in appearance of your horse’s feet. Some horses are very sensitive to slight variations in trimming and shoeing. Radiographs (x-rays) would allow you to determine whether there are any imbalances that may be contributing to her recent change in hoof conformation. A radiographic shoeing consultation would allow your veterinarian and farrier to collaborate on what is best for your horse’s specific ailment.
Underrun heels are one of the most commonly encountered hoof abnormalities. Conformationally, the hoof will appear to have a long toe, low heel, and broken back hoof-pastern axis. Our first inclination is often to improve this axis with a wedge pad, however this may lead to further crushing of the heels. A more successful outcome might be achieved by aiming to redistribute the forces off of the heels, and providing more ground surface contact with the frog and bars. We have had some good success with the use of a “flip-flop” shoe. Although your horse is barefoot, it may benefit from this application for one or two shoeing cycles. This type of shoe has both a pad and metal shoe component. The pad component redistributes the overall forces on the bottom of the foot, and the shoe component is abbreviated and does not extend to contact the heels. With the heels predominantly unweighted, this can promote heel growth.