Intervertebral Disc Disease

Which breeds are most likely to be affected with Intervertebral Disc Disease?   By far the most commonly affected dog is the Dachshund. However, the Shih Tzu, (along with Pekingese, Lhasa Apso, Welsh Corgi, and the Beagle) are also commonly affected. This in no way implies that your dog will be affected; but it is a good idea to have an understanding of the disease in case your dog is affected.     Spangles, who had successful surgery for a ruptured disc at Davies Veterinary Specialists

The dog’s spinal column consists of the spinal cord that is protected by the vertebrae.  The intervertebral discs are structures that lie between the individual vertebrae and act as a cushion between the discs.  Each disc has a fibrous tissue outer layer called the annulus fibrosus that surrounds a soft inner core called the nucleus pulposus (similar to a jelly filled doughnut).

Intervertebral disc disease is a premature hardening of the centre of the disc, and weakening of the outer layer of the disc that occurs in chondrodystrophic dogs such as dachshunds. As the outer layer of the disc ruptures, the inner material is displaced upwards against the spinal cord.  This herniated disc material injures the spinal cord and results in cord swelling and compression.  Consequentially, the  nerves within the spinal cord travelling to the legs and urinary bladder become damaged.  This in turn results in loss of limb function that can range from weakness to paralysis, and loss of bladder control.

 In some cases, the damage to the spinal cord is minor, clinical signs are mild, and anti-inflammatory drugs such as methylprednisolone can be given to decrease the swelling in the cord and allow function to return.  If methylprednisolone is given,

the animal may feel better and may want to be active.  However, it is extremely important that the dog is strictly confined to prevent further herniation of disc material.  In about 4-6 weeks, the rupture heals and the dog can resume normal activity.

In other cases, the amount of disc material compressing the cord is too great and conservative therapy is unsuccessful. These dogs require surgery to remove a section of bone over the spinal cord (hemilaminectomy), and to remove the herniated disc material in order to relieve the pressure on the cord. Before surgery can be done, radiographs (x-rays) and a myelogram (a special x-ray in which dye is injected around the spinal cord) must be performed to identify the area of the spinal cord that is involved. After surgery, the prognosis is still guarded. Unless there has been severe damage to the cord, most dogs will regain some degree of neurological function may and be able to walk.

Some dogs have such severe damage to the spinal cord that they can no longer feel when their toes are pinched and are said to be “deep pain negative.”  In this group of dogs the prognosis for regaining use of the legs is very poor.   These dogs can still receive decompressive surgery and if the cord appears intact, we can wait to see if the dog regains function.  After 6 months, if the dog has not regained function it is highly unlikely that the dog will walk again.

http://www.vetspecialists.co.uk/

http://www.vet.purdue.edu/cpr/

Borrowed from bakalo.com