What is Degenerative Myelopathy?
Degenerative Myelopathy (also known as DM) is an adult onset, progressive disease that affects the spinal cord and peripheral nerves of dogs. It is thought to be similar to Amyotrophic Lateral Sclerosis (ALS, or Lou Gehrig’s disease) in humans. It is caused by a genetic mutation in the SOD1 gene.
- Typically does not affect dogs under the age of 5
- Welsh corgis and German shepherd dogs are the most commonly affected breeds, but DM has also been reported in Bernese mountain dogs, boxers, English cocker spaniels, great Pyrenees, pugs, whippets, and other breeds, as well as mixed breed dogs.
DM is a non-painful, progressive disease.
- Early – Loss of coordination (ataxia) in the hind limbs. Owners may notice scuffing on the hind toe nails or knuckling of the hind feet. This tends to be more pronounced on slick surfaces, such as smooth flooring. This progresses to hind limb weakness that makes it difficult to jump into a car or go up stairs. Some dogs will criss-cross their hind feet when walking or turning. At this stage, dogs may need to be taught to use a ramp rather than stairs and may require foot protection.
- Intermediate – Muscle weakness progresses in the hind legs, and the muscles atrophy. At this point, dogs may have difficulty standing and may require a cart for mobility.
- Advanced – Weakness progresses to the front limbs. Loss of fecal and urinary continence.
A genetic test is available through Orthopedic Foundation for Animals. The test is done with a cheek swab and can be done at home.
The test identifies dogs that are either: 1) clear and have two normal copies of the gene, or 2) carriers that have a normal gene and a mutated gene, or 3) at-risk dogs that have two mutated genes.
Note: this test is not a diagnosis of degenerative myelopathy because not all dogs that have two mutated genes will go on to develop DM.
Unfortunately, there is no cure for degenerative myelopathy.
However, rehabilitation can significantly increase survival time in dogs that have been diagnosed with DM.
The focus of rehabilitation is to maintain core strength and balance, limb strength and endurance. The goal is to maintain mobility for as long possible.
Exercise is modified at the condition progresses.