Horses sometimes get problems with their navicular bone and surrounding tissues. The bone is located on the front of the foot. This is usually behind coffin bone and just below the pastern bone. There are strong tendons that run across this area all the way to the back of coffin bone across the soft tissue. There is some cartilage between navicular bone and the coffin bone. Furthermore there is a small sac just over navicular bone that prevents the bone from abrasion. Navicular bone and surrounding tissues at times get inflamed or degenerates causing disabling and lameness to the horse. Navicular disease in horses should therefore be given attention.
There is no known single cause of this syndrome. However, there are two theories put forward to explain what could be the cause. First, it is believed that compressing of navicular under the tendons and the small pastern bones, as explained above, can cause degeneration of cartilage. This causes the cartilage to flatten and results to it becoming less springy and is unable to absorb bigger shock.Researchers have also found gradual cartilage erosion and degeneration along the surface next to this bone where there was suspected compression. This is associated with biochemical changes and has similarity to human osteoarthritis. This erosion may progress to a point that the underneath bone becomes exposed and thus not protected.
Research has shown gradual but persistent cartilage erosion along the navicular bone in horse with the syndrome. It is believed to be associated with some biochemical changes similar to osteoarthritis in humans. Persistent erosion wears off the cartilage and exposes the underneath bone. This bone constantly rubs against the tendons continually causing inflammation. Compression also makes the bone increase in density and thus becomes brittle. Brittle bones break easily.
Study has also shown that tension on ligaments that support this particular bone could eventually cause bone degeneration. In extreme cases, there is strain on top of inflammation and decreased blood flow to as well as from this particular bone. Since most blood vessels run around this area, tension thickens the blood vessels on this areas leading to lower blood flow.
If blood is restricted from one side, there is a buildup of fluid in this bone. The bone responds to this reduced flow by absorbing mineral that is found at the center of the bone. Extreme tension causes exostoses. This is a case where ligaments get attached to the particular bone and compress it to a canoe shape. The ligaments may also tear in the process.
The treatment offered depends on the extent to which the particular bone is affected. Thus, medication can range from conservative to aggressive. They include therapeutic shoeing, surgery and various medications. The response to treatment is not guaranteed to be positive. Therefore, it is rather advisable to start with less aggressive methods.
Shoeing treatment involves placing a bar across the heels to relieve pressure on these heels. It also improves blood flow. The veterinary can also rasp the quarters of wall of the hoof or cut grooves to relieve contraction. Trimming the foot also aids in balancing the foot. Most horses with the syndrome have long toes, very little inner wall depth and under run heels. Trimming improves the hoof form and structure.
The use of medication involves injection with vasodilators to improve blood flow. There are also anti-inflammatory drugs to treat pain. There are also oral medications aimed at relieving the problem. Surgery involves severing the nerves that could be causing the pain but causes the horse to lose sensation in the back of a foot.
There is no known single cause of this syndrome. However, there are two theories put forward to explain what could be the cause. First, it is believed that compressing of navicular under the tendons and the small pastern bones, as explained above, can cause degeneration of cartilage. This causes the cartilage to flatten and results to it becoming less springy and is unable to absorb bigger shock.Researchers have also found gradual cartilage erosion and degeneration along the surface next to this bone where there was suspected compression. This is associated with biochemical changes and has similarity to human osteoarthritis. This erosion may progress to a point that the underneath bone becomes exposed and thus not protected.
Research has shown gradual but persistent cartilage erosion along the navicular bone in horse with the syndrome. It is believed to be associated with some biochemical changes similar to osteoarthritis in humans. Persistent erosion wears off the cartilage and exposes the underneath bone. This bone constantly rubs against the tendons continually causing inflammation. Compression also makes the bone increase in density and thus becomes brittle. Brittle bones break easily.
Study has also shown that tension on ligaments that support this particular bone could eventually cause bone degeneration. In extreme cases, there is strain on top of inflammation and decreased blood flow to as well as from this particular bone. Since most blood vessels run around this area, tension thickens the blood vessels on this areas leading to lower blood flow.
If blood is restricted from one side, there is a buildup of fluid in this bone. The bone responds to this reduced flow by absorbing mineral that is found at the center of the bone. Extreme tension causes exostoses. This is a case where ligaments get attached to the particular bone and compress it to a canoe shape. The ligaments may also tear in the process.
The treatment offered depends on the extent to which the particular bone is affected. Thus, medication can range from conservative to aggressive. They include therapeutic shoeing, surgery and various medications. The response to treatment is not guaranteed to be positive. Therefore, it is rather advisable to start with less aggressive methods.
Shoeing treatment involves placing a bar across the heels to relieve pressure on these heels. It also improves blood flow. The veterinary can also rasp the quarters of wall of the hoof or cut grooves to relieve contraction. Trimming the foot also aids in balancing the foot. Most horses with the syndrome have long toes, very little inner wall depth and under run heels. Trimming improves the hoof form and structure.
The use of medication involves injection with vasodilators to improve blood flow. There are also anti-inflammatory drugs to treat pain. There are also oral medications aimed at relieving the problem. Surgery involves severing the nerves that could be causing the pain but causes the horse to lose sensation in the back of a foot.
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Understanding Navicular Disease In Horses.