Jewel is a 10-year-old female Yorkipoo—a designer dog. She walked into her vet’s clinic on a Tuesday because of back pain. She was hospitalized that day. On Wednesday, she became paralyzed. On Thursday afternoon, she was referred for evaluation because she was losing deep pain. An MRI revealed a large disc hernia at T13-L1. Surgery was performed late that night.
This is not a completely unusual case. Your local surgeon or neurologist could probably share many similar stories of delayed referral of a paralyzed patient. What can we learn from Jewel’s story?
A Real Jewel
The neurological exam revealed that she was indeed paraplegic, with normal reflexes and minimal deep pain in the hind legs.
The goals of the MRI are to confirm the diagnosis (a disc hernia) and localize the lesion (T13-L1). In addition, the MRI determines the side of the hernia (left vs. right), which dictates the surgical approach.
Surgery entailed a hemilaminectomy and fenestrations.
A hemilaminectomy is a surgical procedure that consists of removing the lateral and dorsal part of the lamina of the vertebrae on either side of the disc space. This allows access to the spinal cord, and in Jewel’s case, to remove the calcified, compressive herniated disc material.
A fenestration is a preventive procedure designed to remove the center, or nucleus pulposus, of intervertebral discs on either side of the hernia. Jewel was considered at risk for another disc hernia in the future.
In fact, the MRI confirmed this suspicion, and revealed that her other discs were calcified. By the way, the annulus fibrosus remains in place, so this is not a fusion.
When should you consider referring a back patient?
* When the patient has proprioception deficits, is ataxic or is dragging the hind legs.
* When the patient is paralyzed.
* When back pain or ataxia is worsening.
* When response to medical management is poor.
* When back pain or ataxia has recurred after a previous episode.
* When the patient becomes worse after pain medications are tapered.
* When you are not sure if a patient has neurologic or orthopedic signs.
Such patients should at least have the benefit of advanced imaging such as a myelogram, a CT scan or an MRI to confirm the diagnosis. If a disc hernia is confirmed, surgery should be performed ASAP.
Occasionally, the patient doesn’t have intervertebral disc disease, but another lesion. One of the goals of advanced imaging is to determine if the condition is compressive or not.
Compressive diseases include disc hernias, tumors, vertebral fractures and luxations, etc. It is important to keep in mind that cats with paraparesis or paraplegia are often thought to have a spinal tumor, but they certainly can have a disc hernia.
Non compressive diseases include fibro-cartilagenous embolus (FCE), granulomatous meningo-encephalitis (GME), degenerative myelopathy, etc.
Spinal diseases, just like any other, perfectly fit the VITAMIN D acronym as mentioned in the sidebar.
The MRI revealed that Jewel had a type I disc hernia, i.e. extrusion of the nucleus pulposus into the spinal canal. This is a classic slipped disc. It typically occurs in small, chondro-dystrophoid breeds. It is due to chondroid degeneration of the nucleus, which herniates through the annulus and compresses the spinal cord. Most type I discs cause acute signs.
This is in contrast to a type II disc hernia, i.e. protrusion of the annulus fibrosus. This is also called a bulging disc. It mostly occurs in larger dog breeds, secondary to fibroid degeneration. The annulus is intact but degenerative, and typically causes chronic compression of the spinal cord.
It may be a good idea to suggest that the owners visit their dogs during hospitalization, ideally when treatments are performed. This could easily be arranged by a treatment technician. This is a great way to show clients how to appropriately take care of their dogs, turn them over, perform physical therapy, etc. It would also be a perfect time to teach them how to express the bladder, an art with which few clients feel instantly comfortable.
After a few days in the hospital, the patient is sent home with instructions for strict confinement to a small, enclosed area; bladder expression or urinary catheter management as needed; land-based and water-based exercises at the local rehabilitation facility if possible; and recumbency management.
Jewel’s story has a happy ending, as she was ambulatory at suture removal, two weeks after surgery.
Regardless, back patients should not be treated casually. Procrastination rarely benefits anybody. The outcome could have been very different and the referring veterinarian’s liability could have been involved.
Sure, even a paralyzed patient with positive deep pain has an 80-90 percent chance of walking again. But we certainly would prefer doing surgery on a patient who is walking than paralyzed. Recovery will be quicker for the patient and easier for the owner.
As surgeons poetically would say, “Don’t sit on a back.”
In spite of several recent articles showing that steroids shouldn’t be used in spinal patients, a common approach is to send a back patient home on steroids. More often than not, no instructions for confinement are given. Steroids may indeed make the patient feel better. She may start running around and jumping on and off furniture. The small disc hernia may suddenly become a big disc hernia that may paralyze your patient. So now what?
If in doubt, you might want to consider calling your local specialist next time you are dealing with a neuro patient (the reasoning would be similar for cervical lesions).
Most (neuro)surgeons actually don’t bite, and would be happy to help you decide how to advise your client and how to provide the best care for your patient.
Applying the VITAMIN D Acronym to Spinal Patients
Here is a non-exhaustive list of spinal conditions.
V –Vascular: Fibro-Cartilagenous Embolus (FCE), saddle thrombus
I –Infectious: Diskospondylitis, Feline Infectious Peritonitis (FIP), Toxoplasmosis, Neospora, distemper
T –Trauma: fracture, luxation
A –Anomalous: deformity, congenital defects
M –Metabolic: Addison, hypokalemia, diabetes mellitus, hypoglycemia, uremia
I –Immune: degenerative myelopathy, myasthenia gravis
–Inflammatory: Granulomatous Meningo-Encephalitis (GME)
–Nutritional: hypervitaminosis A
D –Degenerative: intervertebral disc disease (IVDD), spondylosis deformans
Dr. Phil Zeltzman is a mobile, board-certified surgeon near Allentown, Pa. His website is www.DrPhilZeltzman.com. He is the co-author of “Walk a Hound, Lose a Pound” (Purdue University Press).