Navicular disease is a chronic condition that affects particularly those that take part in races. The cause of this problem remains obscure but the common denominator in all cases is destruction of navicular bones and other tarsal bones. The condition significantly reduces the competitiveness of the horse and is associated with considerable pain. We will look at some facts on navicular disease in horses in this article.
The disease has a gradual onset and initially manifests with intermittent lameness. Since both anterior limbs are usually affected simultaneously, it may go unnoticed for some time. One of the earliest instances that the problem is suspected is during a lunge. Preforming a nerve block on one of the limbs helps to confirm or rule out the problem. Flexing the distal forelimbs may exacerbate the lameness transiently.
There are a number of factors that predispose to this problem. Conformational defects within the hoofs of some horses are said to increase the risk of bone damage and concussion. Such will include, for example, small feet, upright pasterns and long toes among others. The problem with such defects is that pressure is not transmitted evenly within all the bones. The navicular bone is particular under increased pressure which causes destruction over time.
The terrain on which the animal trains is also important. The risk of navicular disease increases if the ground used is irregular and hard. The train that is exerted on the bones and tendons is a lot more and so is the damage. The weight transmitted through the feet also increases a great deal when the horse stands for prolonged periods of time and increases damage to the bony structures in the feet.
Improper shoes are another common predisposing factor. This has been evidenced by the fact that the problem is way common in domesticated horses as compared to those in the world. Improper shoes may prevent expansion of the feet during movement leading to fractures in some bones and ischemia to some tissues due to impaired blood flow. The solution to this is barefoot trimming.
Several treatment options exist. These are categorized as either conservative or invasive (surgical). Conservative options involve proper shoe selection and administration of analgesic drugs. NSAIDs are arguably the most commonly used class of drugs. They provide relief in most affected horses but may lead to some side effects especially in the renal and gastrointestinal systems. Stopping drug administration intermittently helps minimize these side effects.
Steroids should be considered if NSAIDs fail to relieve the pain. The steroids are usually injected into the navicular bursa directly bringing the drug very close to the affected structures. There is reported improvement in up to 80% of affected horses after 4 months of drug administration. The main worry with this mode of administration is an increased risk of tendon rupture.
There are several surgical procedures that may be performed but only as a last resort. It should be emphasized that these surgical operations will by no means cure the condition; they only provide symptomatic relief. One of those that are commonly performed is known as palmer digital neurectomy. Apart from relieving pain, this operation helps to improve competitiveness.
The disease has a gradual onset and initially manifests with intermittent lameness. Since both anterior limbs are usually affected simultaneously, it may go unnoticed for some time. One of the earliest instances that the problem is suspected is during a lunge. Preforming a nerve block on one of the limbs helps to confirm or rule out the problem. Flexing the distal forelimbs may exacerbate the lameness transiently.
There are a number of factors that predispose to this problem. Conformational defects within the hoofs of some horses are said to increase the risk of bone damage and concussion. Such will include, for example, small feet, upright pasterns and long toes among others. The problem with such defects is that pressure is not transmitted evenly within all the bones. The navicular bone is particular under increased pressure which causes destruction over time.
The terrain on which the animal trains is also important. The risk of navicular disease increases if the ground used is irregular and hard. The train that is exerted on the bones and tendons is a lot more and so is the damage. The weight transmitted through the feet also increases a great deal when the horse stands for prolonged periods of time and increases damage to the bony structures in the feet.
Improper shoes are another common predisposing factor. This has been evidenced by the fact that the problem is way common in domesticated horses as compared to those in the world. Improper shoes may prevent expansion of the feet during movement leading to fractures in some bones and ischemia to some tissues due to impaired blood flow. The solution to this is barefoot trimming.
Several treatment options exist. These are categorized as either conservative or invasive (surgical). Conservative options involve proper shoe selection and administration of analgesic drugs. NSAIDs are arguably the most commonly used class of drugs. They provide relief in most affected horses but may lead to some side effects especially in the renal and gastrointestinal systems. Stopping drug administration intermittently helps minimize these side effects.
Steroids should be considered if NSAIDs fail to relieve the pain. The steroids are usually injected into the navicular bursa directly bringing the drug very close to the affected structures. There is reported improvement in up to 80% of affected horses after 4 months of drug administration. The main worry with this mode of administration is an increased risk of tendon rupture.
There are several surgical procedures that may be performed but only as a last resort. It should be emphasized that these surgical operations will by no means cure the condition; they only provide symptomatic relief. One of those that are commonly performed is known as palmer digital neurectomy. Apart from relieving pain, this operation helps to improve competitiveness.
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