It is a catch all term that means a horse has caudal heel pain (pain in the heels of his front feet) but bone damage cannot be seen on an x-ray.
Navicular disease means the same thing, but bone loss/damage is evident on the x-ray.
The navicular bone is a small bone that sits behind the coffin bone. It is attached by tendons above and below. The navicular bursa is a fluid filled sac which sits behind the navicular bone and in front of the Deep Digital Flexor tendon (DDFT). The navicular bursa cushions the bone from the DDFT which slides across the back of the navicular bone. The DDFT is responsible for flexing the foot. The impar ligament is a tiny ligament which attaches the navicular bone to the coffin bone.
Repeated toe first landings cause navicular syndrome! How's that for a simple explanation!
At one time it was thought that a horse first developed navicular disease and then started landing toe first. This is not the case. It is the toe first landing itself which causes navicular disease. This was determined back in the 1970's in a study done with cadaver feet by James Rooney DVM.
Here's where it gets tricky. I think the best thing for a weak digital cushion is lots of exercise with lots of heel first and flat footed landings. This will actually cause the digital cushion to change and become more cartilaginous which will protect the heel from pain.
The problem is how to make a horse stop landing toe first when landing heel first hurts even more.
The answer is boots and pads.
I've used the Easy Boot RX which is a rehab boot designed for recovering from an injury when the horse is not very mobile. It can also be used for light workouts. The soles of the boot offer a thick soft cushion that can encourage a flat footed or heel first landing. Inserting dome pads in the boots adds extra cushioning. If your horse gallops around like a loon he will destroy these boots. I would not recommend leaving the boots on 24/7. They should be put on when you are exercising your horse.
I like to walk around in a large field on a 45' Parelli line attached to a rope halter and change direction of the circle often. It's less boring than a round pen for the horse. Moving in a circle will force your horse to bend and use his shoulders.
If you horse really tries to avoid going in one direction (right or left) it could mean that the outside foot in the direction he does not want to go hurts more than the other foot.
Build your horse up slowly. Ideally you would exercise your horse for 45 minutes a day, 7 days a week but it will take a long time to get to that level of activity. If you can’t workout every day try for every second day. It may take 6 months to 2 years for your horse to heal navicular syndrome.
I've also used the Easy Boot Epics with dome pads. The dome pads are essential for a flat footed or heel first landing. Boots without pads are just another peripheral loading device and will not promote a heel first landing. I've also added flat foam pads underneath the dome pads for added cushioning. Do what ever it takes to get a flat footed or heel first landing.
Avoid lots of up hill work because that will force him to land toe first which is what we want to avoid.
Toe walking forces the horse to use accessory muscles in his shoulder and neck that he wouldn't normally use. His neck and shoulders will be as hard as a rock and extending his leg forward will be difficult. As you lunge your horse stop every 5 minutes or so and stretch his front legs. Mild stretches when he is already warm are best. It's easy to learn half a dozen different types of stretches. Regular massages will also work well to loosen his muscles.
Here are my trimming suggestions for navicular syndrome caused by a weak digital cushion:
If you want help fitting boots on your horse or trimming his/her hooves, please call me at 250 377-1104 (Pacific Time). Also check my barefoot trimming services page for more information and to request a quote by email.
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