Wobbler's Research
Ronaldo C. da Costa, DMV, MSc, PhD, Dipl. ACVIM – Neurology
Department of Veterinary Clinical Sciences
The Ohio State University

What is wobbler syndrome?
Wobbler syndrome is a neurologic disease of dogs that affects their spine in the neck region. It is a very important and common cause of neurologic disability in large breed dogs.

Are there other names for Wobbler syndrome?
Wobbler syndrome or wobblers is the most common name used but the Veterinary literature has used 14 different names to describe this condition. This is in part due to the confusion regarding the mechanisms causing the disease. The name most commonly used in veterinary articles is cervical spondylomyelopathy (which means a disease of the neck vertebrae affecting the spinal cord). Other common names are CVI – cervical vertebral instability, CVM – cervical vertebral malformation, CVMM – cervical vertebral malformation-malarticulation, and cervical spondylopathy.

What are the signs of Wobbler syndrome?
Dogs with wobbler syndrome typically have a “wobbly” gait mostly in the back end (thus the name “wobblers”). This wobbly gait may only be visible on slippery floors and when the dog walks slowly. They may walk with their head down, which is usually a sign of pain. In the more advanced stages of the disease the problems become obvious in all four legs, and they may have trouble getting up, appear very weak, and even “buckle over” with the front legs. Approximately 5% of dogs with wobblers may become acutely paralyzed in all four legs.

Which kind of dog gets wobbler syndrome?
Wobbler syndrome is primarily a disease of large and giant breed dogs. Small breed dogs occasionally get the disease but it is uncommon. In a study with 104 dogs with wobblers only 5 were small dogs.

What are the breeds most commonly affected?
Dobermans and Great Danes are the breeds most commonly affected. A recent survey of the Veterinary Medical Database showed that 4.2% of Great Danes have wobblers, whereas the disease is present in 5.5% of Dobermans. Other breeds are Rottweilers, Mastiffs, Weimaraners, German Shepherds, Bernese Mountain dogs, and Swiss Mountain dogs, but any large or giant breed dog can have the disease.

Is the disease the same in Dobermans and Great Danes?
Generally speaking no, the disease tends to be different in these breeds. Dobermans usually have the disease when they are middle aged to older (mean age 6 years), whereas Great Danes are typically younger (mean age 3 years).

What causes the disease?
We don’t know yet what exactly causes the disease. Many people believe that there is a genetic basis for the disease, which may well be true, but the evidence for genetics is still not clear. We are investigating the genetics of the disease in Dobermans and have plans to study it in Great Danes in the future.

Why do they have the neurological signs or pain?
The neurological signs happen because affected dogs typically have spinal cord compression. The compression can be caused by a combination of a small spinal canal with disc herniation (as commonly seen in large breeds such as the Doberman), or a small spinal canal secondary to bony changes impinging upon the spinal cord (typically seen in Great Danes). The spinal nerves or nerve roots can also be compressed. When the nerves are compressed this causes a great deal of pain/discomfort.

How can I find out if my dog has wobblers?
Your dog has to be first examined by your Veterinarian. During the examination he/she will perform a physical and a neurological examination to find out if the reason for the difficulty in walking can really be attributed to a neck/neurologic problem.
To specifically diagnose the disease we need to do some imaging tests. We typically do X-rays first to see if we can identify any obvious bony lesion or diagnose other diseases that can mimic wobbler syndrome. To confirm the disease more advanced imaging tests are required. In the past we used to do myelograms (an X-ray with dye injected around the spinal cord). This technique is rarely used these days because there are better, more sensitive tests. The best test is an MRI (magnetic resonance imaging). We have specifically compared MRI and myelogram in 18 dogs with wobblers and MRI was superior. MRI is also very safe. We do not see any neurological worsening after MRIs, whereas this happened frequently with myelograms (even though the worsening was mild and temporary). A CAT scan (computed tomography) is a good test too, but probably not as good as the MRI because we can not see well the spinal cord without using dyes. Typically these tests are done by specialists in larger Hospitals or specialty clinics.

What are the treatment options?
Dogs can be treated medically or surgically. Medical management usually consists on the use of anti-inflammatory drugs (steroidals or non-steroidals) with restricted activity. Because they have a neck problem, neck leashes should not be used, and a chest harness is strongly recommended.

How is surgery done?
Surgery can be done in many different ways. There are at least 21 different types of surgery to treat wobbler syndrome. Several factors must be taken into consideration when deciding on the type of surgical treatment, for example how severe are the symptoms, how many lesions are present in the spine, how severe is(are) the spinal lesion(s), the presence of other concurrent medical conditions, such as dilated cardiomyopathy, etc. The attending Neurologist or Surgeon will discuss the options with owner, taking into consideration the short and long term expectations of the family.

What is the success of the treatment?
We have done a study looking at the success of surgery and medical management of wobblers in 104 dogs. Based on that study we learned that approximately 50% of dogs will improve with medical management, approximately 30% will remain stable and 20% will worsen. Surgical treatment offered a success rate of approximately 80%. The other 20% of dogs either remained stable or worsened. We have had very good success with both medical and surgical management.

Would wobblers shorten the life expectancy of my dog?
It might. Again, it depends on how severe are the spinal lesions, how much neurological impairment is present and the type of treatment. Typically, based on our studies, the mean survival time of dogs with wobblers is approximately 4 years after the diagnosis.

Are you doing any studies at Ohio State?
We have a strong program to better understand and treat dogs with wobbler syndrome. Currently we have a major project studying the disease in Great Danes (please see below more information).

Anatomic and functional characterization of Great Danes with and without signs of wobbler syndrome. This study aims to characterize and to compare the presence of spinal abnormalities in normal and wobbler Great Danes using MRI and other tests. In previous studies in Dobermans we found that many clinically normal Dobermans had severe changes in their spine, yet they had no signs of wobblers. This information was crucial to allow a better understanding of the disease in Dobermans. As almost 1 out of 20 Great Danes have wobblers, we need to have a better understanding of the disease in the breed. We are enrolling 30 Great Danes (15 normals, 15 with wobblers). The study will cover all the costs for the normal Great Danes who volunteer to help with this study. Also, the study will cover the cost of the MRI for the Great Danes affected with wobblers. This study will be part of the PhD thesis of one of the Neurology residents. This study is being graciously supported by the Great Dane Club of America.

Question/comments please contact:
Dr. Ronaldo C. da Costa, DMV, MSc, PhD, Dipl. ACVIM – Neurology – (dacosta.6@osu.edu)

Dr. Paula Martin-Vaquero, DVM (Paula.Martin@cvm.osu.edu) - Neurology Resident and PhD student

Please see below a list of our published work on Wobbler syndrome.

da Costa, RC. Cervical spondylomyelopathy (Wobbler syndrome). Veterinary Clinics of North America – Small Animal Practice. V. 40, n. 5, p. 881-913, 2010.

Johnson, J, da Costa, RC, Goel, V.J., Allen, MJ. Kinematic motion patterns of the cranial and caudal cervical spine in the dog. Veterinary Surgery. In press, 2011.

Johnson, J, da Costa, RC, Allen, MJ. Micromorphometry and cellular characteristics of the canine cervical intervertebral discs. Journal of Veterinary Internal Medicine. v. 24, n. 6, p. 1343-1349, 2010.

da Costa, RC, Johnson, J, Parent JM. Are cervical vertebral ratios useful in the diagnosis of cervical spondylomyelopathy in Dobermans? Proceedings of the 28th Annual American College of Veterinary Internal Medicine Forum, ACVIM Forum, Anaheim, CA, 2010.

da Costa, RC, Echandi RL, Beauchamp D. Computed tomographic findings in large and giant breed dogs with cervical spondylomyelopathy: 58 cases. Journal of Veterinary Internal Medicine, v 23, n. 3, p.709, 2009.

da Costa, RC, Parent JM. Magnetic resonance imaging findings in 60 dogs with cervical spondylomyelopathy. Journal of Veterinary Internal Medicine, v 23, n. 3, p.740, 2009.

da Costa, RC. Cervical spondylomyelopathy: recent advances. Proceedings of the 34th World Small Animal Veterinary Association Congress (WSAVA), June 21-24, 2009.

da Costa, RC; Parent, J; Holmberg, DL; Sinclair, D; Monteith, G. Outcome of medical and surgical treatment in dogs with cervical spondylomyelopathy – 104 cases. Journal of the American Veterinary Medical Association, v. 233, p. 1284-1290, 2008.

da Costa, RC; Parent, J. One-year clinical and magnetic resonance imaging follow-up of Doberman pinscher dogs with cervical spondylomyelopathy treated medically or surgically. Journal of the American Veterinary Medical Association, v. 231, p. 243-250, 2007.

da Costa, RC. Pathogenesis of Cervical Spondylomyelopathy: Lessons from recent years. Proceedings of the 25th Annual American College of Veterinary Internal Medicine Forum, ACVIM Forum, June 6-9 2007, Seattle, WA.

da Costa, RC. Wobbler syndrome (cervical spondylomyelopathy). In: Tilley, LP; Smith, FWK. Blackwell’s 5 Minute Veterinary Consult: Canine and Feline. Blackwell Publishing, 4th Ed, 2007, p. 1442-1443.

da Costa, RC; Parent, J; Dobson, H; Holmberg, DL; Partlow, G. Comparison of magnetic resonance imaging and myelography in 18 Doberman pinscher dogs with cervical spondylomyelopathy. Veterinary Radiology and Ultrasound, v. 47, n. 6 p. 523-531, 2006.

da Costa, RC; Parent, J; Partlow, G; Dobson, H; Holmberg, DL; LaMarre, J. Morphologic and morphometric magnetic resonance imaging features of Doberman pinscher dogs with and without clinical signs of cervical spondylomyelopathy. American Journal of Veterinary Research, v. 67, n. 9, p. 1601-1612, 2006.

da Costa, RC; Poma, R; Parent, J; Partlow, G; Monteith, G. Correlation of motor evoked potentials with magnetic resonance imaging and neurological findings in Doberman pinscher dogs with and without clinical signs of cervical spondylomyelopathy. American Journal of Veterinary Research, v. 67, n. 9, p. 1613-1620, 2006.

Ronaldo C. da Costa, DMV, MSc, PhD, Dipl. ACVIM - Neurology
Assistant Professor and Service Head, Neurology and Neurosurgery
Department of Veterinary Clinical Sciences
College of Veterinary Medicine
The Ohio State University
601 Vernon L. Tharp Street
Columbus, OH 43210-1089
Telephone: (614)-292-3551
Telefax: (614)-292-0895
E-mail: dacosta.6@osu.edu


JP Yousha
Chmn., Health & Welfare Committee
Great Dane Club of America
432-684-8940 (CT-USA)


Permission to reprint as submitted for educational purposes is given. 
Submitted by JP Yousha, Chair, H&W Committee, GDCA 2011.