`Wobbler´s Syndrome´ is the term used to refer to compression of the cervical spinal cord in Doberman Pinschers and Great Danes. This disorder has many names- it is also called cervical vertebral instability, cervical vertebral malarticulation/malformation, cervical vertebral stenotic myelopathy, and cervical spondylopathy - which is probably why most of us refer to it simply as `Wobbler´s.´
Wobbler´s is characterized by progressive neurological dysfunction of all four limbs, usually starting with the hind legs. Common symptoms are an abnormal `drunken´ or `wobbly´ gait, scuffing or dragging of the hind feet, a short, choppy gait of the front legs, neck pain, and holding the head and neck in a flexed (downward) position. Signs may progress to the point where the dog may not be able to walk or get up on its own.
Wobbler´s usually occurs in older Dobermans (3 to 8 years of age) although it has been reported in dogs less than two. The spinal cord compression occurs in the lower neck, most commonly in vertebrae C5, C6 and C7. Some dogs may have multiple areas where the spinal cord is compressed. The compression of the spinal cord can be caused by many things, the most common being:
1) Congenital malformation and/or malarticulation of the vertebrae- A misshapen vertebra, or one that doesn´t align properly with its neighbor can press on the spinal cord.
2) Instability of the vertebrae- usually due to malarticulation. This instability often results in hypertrophy (enlargement) of the ligaments associated with the vertebrae, which act to hold the vertebrae in their proper place. Both instability and hypertrophy of the ligaments can put pressure on the spinal cord.
3) Stenosis (narrowing) of the spinal cord canal- Stenosis can be caused by malformation of the vertebrae, or by hypertrophy of the ligaments associated with the vertebrae. This narrowing of the canal will cause compression of the spinal cord.
4) Protrusion of the intervertebral disks (`slipped disk´)- A disk can protrude from it´s place between the vertebrae and press on the spinal cord due to malarticulation or instability of the vertebrae. It should be noted that Dobermans with no malformation or malarticulation can also have slipped disks- that is not Wobbler´s Syndrome, that is a dog with Intervertebral Disk Disease.
As you can see, all of the above causes of spinal cord compression are inter- related; because of this, most dogs have more than one cause of compression- however, there usually is one cause that is responsible for the majority of the pressure on the spinal cord.
Treatment of Wobbler´s depends on the severity of the spinal cord compression. Milder cases may respond to rest and corticosteroid (i.e. cortisone) treatment to reduce the inflammation and swelling of the spinal cord. Acupuncture has also been shown to be helpful, especially in relieving pain. Chiropractic adjustment has also been suggested- however, in the case of a dog that has instability of it´s vertebrae, chiropractic adjustment has the potential to cause serious complications. In more severe cases, surgery is the only option. A myelogram or MRI must be done prior to surgery to determine where the compression is, whether there is more than one area of compression, and how severe the compression is. The type of surgery that is performed depends on the cause of the compression. Common surgical procedures performed are a dorsal laminectomy, a ventral slot procedure, a stabilization procedure or a combination of the above. Surgery usually carries a 75% success rate for either stopping the progression of the disease or improving clinical signs if the dog can still walk prior to surgery. The rate falls to 50% in dogs that can no longer walk prior to surgery.
The cause of Wobbler´s Syndrome is still unknown. Genetics, conformation of the neck, nutrition, injury- all have been theorized to play a part. Neck x-rays prior to breeding have been suggested, but since the malformation and malarticulation in an unsymptomatic dog can very subtle, they can be very difficult to interpret. Preventative breeding can be frustrating as most dogs do not show symptoms until they are past their prime breeding age. The best we can do at this point in time is to be aware of Wobbler´s in our pedigrees, and breed responsibly.