Degenerative myelopathy is a progressive disorder caused by of the lower spinal cord. The cause is unknown, though genetic and immune mediated mechanisms are suspected. It occurs mainly in older dogs, with German Shepherds, Labradors and other large breeds most commonly affected. It is not specifically recognized in cats.
What are the symptoms?
Since the lower spinal cord gives rise to the nerves that control the rear legs, bladder and colon, these are the areas affected. Owners most commonly notice difficulty rising, scuffing of the back feet, stumbling or a swaying gait. In some dogs, muscle atrophy (decreased muscle tone) can be dramatic. Difficulty controlling stool and urine is common as well.
How is it diagnosed?
There is now a blood test for degenerative myelopathy, available through the University of __________ diagnostic lab. This test is used to confirm the disease, as well as gather valuable information for scientists studying this problem in dogs.
In many cases, the diagnosis is made based on physical and neurologic exam findings, coupled with a typical age and breed. Ruling out other causes of rear leg weakness, such as arthritis or spinal cord tumors is helpful for prognosis and treatment decisions, but not always necessary.
Is it curable?
Degenerative myelopathy is not curable. Treatment options focus on supportive and palliative care.
What treatments are available?
Most dogs with degenerative myelopathy will benefit from pain medications. Pain medications can treat concurrent arthritis, or relieve pain/stress in overworked muscles in their back, forelegs or neck. Medications to increase bladder tone can help with incontinence.
Acupuncture, laser and massage have shown great promise in treating dogs with degenerative myelopathy. These physical medicine modalities can stimulate the weakened muscles and nerves in the back legs, as well as improve control of urination and defecation.
Progressive neurologic weakness, such as seen in DM, can also benefit from therapeutic exercise and rehabilitation. Retraining the muscles, and/or teaching the pet how to compensate for the disability can improve function and general quality of life. Tools such as harnesses and wheelchairs can be enormously beneficial for some dogs and their families.
What should I expect?
As the degenerative myelopathy progresses, dogs become weaker and more unstable in the hind end. Urinary and fecal incontinence often becomes evident.
In the later stages, dogs may become completely paralyzed and incontinent. Forelegs and breathing mechanisms will eventually be affected.
Is degenerative myelopathy painful? Degenerative myelopathy itself is not painful. That being said, many of these patients have arthritis or other painful conditions that need to be addressed. In addition, many dogs with rear leg weakness become painful in their neck, back, and forelegs from the effort of “pulling” themselves along with their front end.