By Dani Powers, DVM, DACVIM (Neurology)
Disk related problems are very common in our canine patients, in fact it is the most commonly encountered spinal problem in dogs. Intervertebral disk disease or IVDD is common terminology used, but others include: herniated, slipped, ruptured, extruded or bulging disk. All refer to a similar process, which is degenerative changes to the disk with and without spinal cord compression.
Chondrodystrophic breeds are more prone to disk related problems, however IVDD also occurs in non-chondrodystrophic dogs and occasionally cats. A chondrodystrophic breed is basically the “long and short” breeds including Dachshunds, Beagles, Bichon Frise, Lhasa Apso, Bassett Hounds, Pekingese, Shi Tzus, etc. A non-chondrodystrophic breed is all others, essentially medium and large breed dogs, however we commonly see Labrador Retriever and German Shepherd dogs with IVDD.
The disk is composed of 2 main parts including the annulus and nucleus. The annulus is the outer covering and the nucleus is the inner gelatinous portion; these are similar in appearance to a jelly donut.
Disk degeneration can happen in 2 ways, these include Hansen’s Type I and Type II, or chondroid and fibroid degeneration, respectively.
Type I disk disease results in progressive changes to the nucleus (degradation and loss of water) until eventually the nucleus “extrudes” through the annulus layers to cause spinal cord compression and/or contusion. Clinical signs are typically acute in onset and quickly progressive (minutes to hours, maybe days). Clinical signs may include pain, weakness or paralysis. While certain actions such as jumping or stairs can exacerbate a Type I disk extrusion, they are often without a known cause, essentially the disk degenerated beyond the point of normal anatomic function (straw that broke the camel’s back).
Type II disk disease results from progressive changes to the annulus resulting in thickening and degeneration and eventually causes spinal cord compression. Clinical signs are usually insidious and slowly progressive. Clinical signs may include pain, weakness or paralysis.
Both type I and II can occur in any breed, however chondrodystrophic breeds are more common to have type I and non-chondrodystrophic breeds are prone to type II.
Definitive diagnosis (required for surgical intervention) usually involves advanced imaging such as MRI of the spine.
Treatment may be surgical vs medical management (strict rest, pain medication, anti-inflammatory drugs), however determination of the best course of treatment can be made with your family vet and often a referral to a veterinary neurologist.
BIO Dr. Powers is a board-certified small animal neurologist at MissionVet Specialty & Emergency. She joins MissionVet after serving as an associate neurologist at Seattle Veterinary Specialists. She graduated from WSU College of Veterinary Medicine in 2011. Dr. Powers completed a rotating internship in 2012 and her neurology residency in 2015 both at Seattle Veterinary Specialists. Dr. Powers, her husband, their 3 kids and cat are excited for a warmer climate and more sunshine in their move to Texas! Dr. Powers has interest in managing neurosurgical spinal emergencies as well as chronic spinal disease. In addition, she enjoys treating all aspects of brain disease including epilepsy management, brain tumors, degenerative, inflammatory and congenital brain conditions.