pets disease

The vestibular system is a specialized portion of the nervous system found within the inner ear, brain, and spinal cord. Its duty is to maintain a state of equilibrium and balance. By communicating with the nerves supplying the eyes, limbs, and trunk, the body is able to coordinate the position and activity of these regions with movements of the head.
Peripheral vestibular dysfunction (PVD) is a disease that affects the nerves of the vestibular apparatus in the ears. PVD is characterized by a sudden onset of incoordination and loss of balance, which is often accompanied by a head tilt, involuntary twitching of the eyeballs, and in many cases, vomiting. The causes of this disorder can include trauma to the ears, skull infections, and tumors involving the middle or inner ear. Diagnosis of PVD is achieved using clinical signs and various laboratory tests to rule out other potential causes of the symptoms. Radiographs of the skull may be helpful in the detection of any masses or infections that may involve the inner portions of the ears. Treatment, of course, depends on the underlying cause and usually includes high doses of corticosteroid medications designed to reduce inflammation involving the vestibular apparatus.
Vestibular ataxia syndrome is seen in kittens born of queens stricken with feline parvovirus during pregnancy. Owners often are alerted to a problem when these kittens seem to have trouble in attempting to walk. The condition will not improve as these kittens mature, nor will it usually worsen.
Congenital vestibular syndrome is seen in Siamese and Burmese cats, with signs appearing anywhere from 2 to 4 weeks of age. Many of the Siamese cats affected are deaf as well. The prognosis for Siamese cats with congenital vestibular syndrome is good, with clinical signs usually abating by the time the cat is 6 months of age. In Burmese cats, however, the prognosis is not as good, and the poor quality of life for most of these individuals will usually warrant euthanasia.

Problems with Degenerative disk disease (DDD) can show up in smaller breeds as early as 3 years of age. In larger dogs, the onset of signs might not occur until they are 6 to 7 years old. Overweight dogs are at an especially high risk of developing complications associated with intervertebral disk disease.
The clinical signs seen with degenerative disk disease and/or disk rupture depend on the location of the lesion and the amount, if any, of the rupture that has taken place. In fact, the extent of pressure or damage to the spinal cord can be estimated according to the signs seen.
Dogs with early or mild cases of disk disease causing slight pressure upon the cord will be quite painful and reluctant to move. Many will cry or yelp when picked up. If the neck is involved, any manipulations attempted will be met with vigorous protests. These pets often prefer not to be bothered, and have the tendency to isolate themselves. Appetites are usually reduced as well. Since nerve fibers responsible for coordinated muscle movement run within the outer layers of the spinal cord, owners may also notice weakness and/or incoordination when their pet attempts to walk.
With more severe disk ruptures, damage to the deeper portions of the spinal cord can become a serious factor. When this occurs, partial or complete paralysis of one or more limbs might result, depending on the location of the rupture. If the entire depth of the spinal cord is involved, these animals will also lose all pain sensation to one or all four limbs, again depending on the areas of the spinal cord involved. Such severe cases carry a very grave prognosis, since treatment at this stage is rarely successful.
In most cases, confirmation of a ruptured disk is made via a thorough examination, clinical signs, and with radiographs of the vertebral column. If the exact location of the spinal lesion cannot be pinpointed with regular radiographs, a special test, called a myelogram, is performed. This test involves injecting a dye directly into the spinal canal. The dye, which can be identified on a radiograph, helps outline the cord lesion and demonstrate the extent of the disk rupture.
The type of treatment instituted for disk disease and/or rupture depends on the extent of the damage done by the disk to the spinal cord.
For those dogs showing only pain with some mild incoordination, a strict 2 week confinement period, either at home or in a hospital setting, is a must Afterward, short 10- to 15-minute physical therapy sessions, including swimming, can be performed twice daily to help speed recovery and return to normal function.
For cases in which the affected dog is having great difficulty walking, strict cage confinement combined with anti-inflammatory therapy and other specific treatment is indicated. If the disease is such that the dog is unable to support weight on the limbs at all, even after medical therapy, then surgery is required to reduce the pres- sure placed on the spinal cord by the ruptured disk.
This surgery, called a laminectomy or hemilaminectomy, works best if performed within the first 24 hours of the injury. It involves the removal of part of the vertebra over the affected cord segment. By eliminating the enclosed space through which the spinal cord runs, the pressure on the cord caused by the inflammation is allowed to dissipate. At the same time, surgeons often elect to perform intervertebral disk fenestrations, aimed at removing the offending nucleus pulposus from the disk in question and from adjacent disks as well.
The prognosis is poor for those pets that are unable to walk and have lost deep pain sensation in their legs as a result of a ruptured disk. The loss of deep pain indicates that the entire depth of the spinal cord is invariably involved, and surgical salvage procedures are rarely successful.
In those instances where surgery is unsuccessful, or in which paralysis is permanent, euthanasia is not always the only option left to the owner. Special “wheelchairs” for dogs have been developed for dogs paralyzed by a ruptured disk or other neurological accidents. Although not suitable for every patient, these carts can help afford mobility to select patients willing to wear the apparatus and an alternative for those owners willing to devote much time and care to their paralyzed pet. If you think that such a device could be applicable to your own pet’s situation, ask your veterinarian for more details regarding this and other management options available.
There are specific measures that pet owners can take to help protect their dog from a ruptured disk. The first and most important is to prevent obesity. Overweight dogs are prime candidates for such complications; hence, they should be placed on a strict diet to reduce this risk factor.
Jumping should be discouraged in dogs predisposed to intervertebral disk disease. Many ruptured disks result from pets jumping off and on furniture. Pets so inclined should be assisted up or down whenever possible. Even better, a small chair or ramp can be placed in front of the dog’s favorite piece of furniture to allow easier access.
Whenever lifting a dog with back problems, be sure to firmly sup- port both the front and hind ends, keeping the back as straight as possible. This stabilizes the position of the spine and affords the handler with better and safer control should the pet struggle.
Surgical intervertebral disk fenestration is often used as preventive measures in dogs that have previously suffered from bouts of inter- vertebral disk disease. As mentioned before, this involves the penetration and removal of the nucleus pulposus from one or more intervertebral disks suspected of causing current or future problems. If this is done, the danger associated with later disk rupture is removed with the nucleus.

Coursing along the length of the back, the spinal cord travels protected within the bony vertebral column. Separating each vertebra, and located beneath the spinal cord itself, are structures called intervertebral disks, which serve as cushions between each individual vertebra, absorbing shock and forming joints that allow the vertebral column to bend. Each circular disk is composed of an outer band of tough, fibrous tissue called the annulus fibrosus surrounding an inner gelatinous center called the nucleus pulposus. This latter structure is responsible for absorbing any shock placed on the disk.
Degenerative disk disease (DDD) is characterized by the slow degeneration of the nucleus pulposus within one or more intervertebral disks. As these continue to degenerate, they become less resilient and can even calcify, leaving the intervertebral disk without its shock-absorbing unit. As a result, the disks so affected become very susceptible to compression damage, even from normal day-to-day activity. In pets so affected, continued stress or sudden trauma to the disk or vertebral column can lead to an overt tearing or rupture of the annulus fibrosus, and extrusion of the degenerating nucleus pulposus. Unfortunately, since the top portion of the annulus is much narrower than the bottom portion, this extrusion usually occurs upward directly into the spinal canal, damaging the spinal cord and associated nerves.
Overt disk ruptures may be classified as partial or complete. In partial ruptures, the annulus can either be stretched or displaced into the spinal canal, or it can partially rupture, allowing a small amount of the nucleus within to escape and pressure the spinal cord. With complete ruptures, the entire nucleus content is allowed to escape into the spinal canal. Obviously, the consequences of such a rupture versus a partial one are much more severe.
The region of the vertebral column most susceptible to rupture is that portion extending from the last rib to the pelvis. The neck region is another area that can be affected. In a pet suffering from Degenerative disk disease (DDD), even the slightest wrong move, such as jumping off the couch or running too fast, can cause an affected disk to rupture. Dogs are the species primarily afflicted with Degenerative disk disease (DDD). Although any dog can suffer from DDD, there do seem to be some breed dispositions. The dachshund breed certainly leads the list in the number of cases reported. Other breeds commonly afflicted with degenerative disk disease include poodles, Pekingese, and Lhasa apsos. Beagles and cocker spaniels also have a notable incidence of Degenerative disk disease (DDD) in their neck region.