Intervertebral Disc Disease
Intervertebral disc disease (IVDD) is a condition that affects the spinal column of dogs. It occurs when the discs between the vertebrae bulge or rupture. The condition causes pain, nerve damage, and sometimes, paralysis.
The spine is composed of multiple bones called vertebrae. The vertebrae protect the spinal cord, which carries nerve signals between the brain and the body. Intervertebral discs are located between vertebrae, where they absorb shock.
Intervertebral discs consist of a fibrous outer shell (annulus fibrosus) and a gelatinous interior (nucleus pulposus).
There are two types of IVDD. Type I Disc Disease occurs when the gelatinous nucleus pulposus becomes mineralized. This hardened material pushes through the disc’s outer shell, causing compression of the overlying spinal cord. Type I disease usually occurs as an “acute” injury, often related to motion.
Type II Disc Disease is a slower, degenerative process. It occurs when the outer shell of the disc collapses and protrudes upward, placing pressure upon the spinal cord.
Dogs affected by Type I IVDD often seem fine one minute, then in pain the next. This may occur after a normal activity, such as walking up the stairs. Affected dogs may have hind limb weakness or paralysis. Type I IVDD commonly affects dogs with long backs and short legs, such as Dachshunds.
Dogs affected by Type II IVDD show similar symptoms as dogs with Type I disease, except that the symptoms usually develop over a longer period of time. Older, large breed dogs, such as German Shepherds, are predisposed to this type of IVDD.
If you think your dog has IVDD, he or she should be examined by your veterinarian, who will carefully evaluate for sensitivity on palpation of the back or neck in the region of the injury. They will also evaluate for decreased proprioception (knowledge of where the dog’s feet are in space) and decreased sensitivity in the limbs.
If your veterinarian suspects IVDD, they will probably recommend spinal x-rays. X-rays are important to rule out other causes of your pet’s symptoms, such as spinal fractures, dislocations, and tumors. A ruptured disc location can often be identified by x-rays, although x-rays are not always diagnostic.
Advanced imaging, such as CT or MRI, is often required for a definitive diagnosis.
Depending on the severity of the disease, your veterinary doctor will recommend medical or surgical treatment. Surgery offers the best chance of recovery for severely affected dogs, such as those who cannot walk. Medical treatment, consisting of pain control and anti-inflammatory medication, is a reasonable option for affected dogs who are not paralyzed or in severe pain. Treatment must ALWAYS be combined with strict confinement for a minimum of several weeks. Physical therapy may also be recommended.
Treatment affords a good chance of success, although some patients, especially those who have been more severely affected for a longer time, may not recover. Quick recognition of symptoms, veterinary treatment, and strict adherence to your veterinarian’s recommendations afford the best chance for recovery.