Know signs, therapeutic options for canine Wobbler syndrome

Canine Wobbler syndrome is called by many other names depending on the training background of the clinician discussing the subject.

Figure 1

These include caudal cervical vertebral instability and malformation, cervical spondylopathy, and spondylolisthesis, to name a few.

We recognize these dogs as primarily giant and large breeds with the usual history of progressive generalized ataxia and weakness. Occasionally we see an acute onset of signs, perhaps due to trauma or a fall. Close questioning of the client may elicit a history of what was previously interpreted to be simply a "clumsy" Great Dane, Mastiff, Doberman, or other large breed patient. Usually, Great Danes and Mastiffs show clinical signs as young animals, while Dobermans and most other large breeds present at middle age or as a geriatric patient.

Neurologic exam

The neurologic examination should reveal normal mentation and cranial nerves, with any degree of tetraparesis or ataxia. Conscious proprioception is usually abnormal in all four limbs. Lateralization of signs is possible. Spinal reflexes may be normal, exaggerated, or reduced in the forelimbs depending on the severity and location of the cervical lesion(s). Rear limb reflexes are also variable, and evidence for spinal pain on palpation is difficult to find in many of these stoic patients.

If left without definitive treatment most of these dogs will gradually or rapidly "go down."

Often the attending clinician may take some plain cervical spinal radiographs to rule out obvious neoplasia or discospondylitis, and discuss the options of anti-inflammatory medications or acupuncture therapy versus referral to a specialist. It is at this point important to note some recent publications on the subject of surgery for Wobblers.

Figure 2

Important findings

Late in 2002, the journal, "Veterinary Surgery," published an article by Dr. Luisa De Risio et al discussing post operative recovery and long term follow-up in 20 Wobbler dogs treated by dorsal laminectomy. The authors reported on cases treated with this surgical method at Colorado State University and North Carolina State University. This is one of the few papers discussing Wobblers which actually follows the neurological status of the patients long term.

In it they report a length of hospitalization of 8.3 (+/- 7) days, and neurological improvement in 19 of 20 patients postoperatively. These findings are in direct contradiction to the published and oft-repeated mantra of many authors (and others who perform small animal neurosurgery), which holds that prolonged post operative recovery inevitably follows a continous dorsal laminectomy (CDL), and that ventral distraction and fusion techniques are more effective procedures for treatment of Wobblers.

Actually, a strong proponent of the ventral distraction and fusion techniques (Dr. Howard Seim) has published and described the use of dorsal laminectomy techniques in Current Veterinary Therapy XXXIII. Figures 1 and 2 illustrate the end appearance and decompressive effect of the CDL procedure.

Mythology debunked

These two important publications debunk some of the mythology surrounding the dorsal surgical techniques for the treatment of Wobblers. Perhaps now more owners can be offered another option with a reasonable chance of solving the problem. This is especially critical if diagnostics demonstrate "multiple site" Wobbler lesions, which are notoriously poorly responsive to the ventral distraction and fusion techniques.