Wobbler Syndrome

(aka cervical vertebral instability, cervical spondylopathy, cervical spondylomyelopathy)

The Wobbler syndrome is a group of disorders that cause compression of the cervical spinal cord in large and giant breed dogs. The disease is especially common in young Great Danes and older Doberman Pinschers with males twice as likely to be affected as females. The cause of the disease is not completely understood but likely has multiple factors including heredity, nutrition, rate of growth and possibly trauma. The disease can be divided into 5 subclasses based on underlying abnormalities. These include chronic degenerative disc disease, congenital osseous malformations, vertebral tipping, hypertrophied ligamentum flavum and hourglass compression. The end result of all these processes is compression of the cervical spinal cord that results in decreased nerve conduction through the cord.

Clinical signs may include neck pain, difficulty rising, muscle atrophy, an awkward or unsteady gait and lack of coordination. Clinical signs usually are first noted in the rear legs but all four can be affected. A myelogram is needed to confirm the diagnosis and to determine which components of the syndrome are present in each particular patient. The myelogram is a procedure where a needle is placed into the spinal canal of the lower back in the space that contains the spinal fluid. A contrast fluid or dye is injected into this space to outline the entire spinal cord. A series of radiographs are then taken with the neck in various positions of flexion, extension and traction to determine where the cord is compressed and whether or not it changes with position of the neck (static vs. dynamic lesions). We will usually allow the patient to recover from the myelogram prior to initiating any surgical therapy to minimize anesthetic risk.

Medical therapy with cage rest and steroids is predominantly used for very mild cases of Wobblers syndrome. Often the disease is progressive in spite of medical management. Surgery is generally recommended for more severely affected patients or patients that have failed to improve with medical management. The prognosis for improvement depends on the neurologic condition of the patient prior to surgery and is better for less severely affected dogs. Surgical therapy is variable from patient to patient and depends on the underlying cause of cord compression. Options include ventral slot decompression, dorsal laminectomy decompression, ventral stabilization and ventral traction-stabilization. The goal of surgery is to remove the underlying cause of cord compression to allow the cord to function normally. After surgery a neck brace may be used to support the operative site during healing. The dogs are often initially worsened neurologically after surgery and require a lot of nursing care and rehabilitation. This includes pain management, physical therapy and basic nursing care. Recovery time and prognosis depend on the underlying cause and severity of neurologic deficits before and after surgery and hospitalization can be prolonged. Dogs that are able to walk but are uncoordinated have a better prognosis than dogs that are paralyzed and unable to stand. Surgery will generally improve the dog's function and limit the progression of clinical signs. The degree of improvement depends on the amount of spinal cord damage already present.