What is Degenerative Myelopathy?

Degenerative myelopathy is a chronic, progressive condition in dogs characterized by the degeneration of the white matter of the spinal cord. The spinal cord’s role is to transmit nerve signals between the brain and the limbs — when it deteriorates, nerve communication becomes disrupted. DM typically begins later in life (often after about 8 years of age) and is most frequently seen in large or giant breeds, especially German Shepherd Dogs, Pembroke Welsh Corgis, Boxers, and Chesapeake Bay Retrievers. 

The disease often involves a genetic component. A mutation in the superoxide dismutase 1 (SOD1) gene has been strongly associated with DM in many breeds. Being homozygous for the mutated form of this gene (having two copies) puts a dog at increased risk of developing DM, although not all genetically at-risk dogs will become clinically affected, and other genetic and environmental factors likely play a role. 

Recognizing Signs & Symptoms

DM typically progresses slowly and can be mistaken initially for arthritis or other orthopedic issues. Common signs include:

Early Signs

• Weakness in the hind limbs

• Unsteady, wobbly gait (ataxia)

• Difficulty rising from a lying or sitting position

• Dragging hind feet (often with worn nails or scuffed paws)

• Hind legs that cross or knuckle when walking 

Progressive Symptoms

As the disease advances:

• Hind limb weakness becomes more pronounced

• Dog may lose the ability to walk without support

• Muscle atrophy (wasting)

• Urinary and fecal incontinence

• Eventual involvement of the forelimbs and difficulty with eating or breathing in advanced stages 

It’s important to note that DM is not usually painful in itself, although secondary injuries (scraped paws, muscle strain) may cause discomfort. 

How Degenerative Myelopathy Is Diagnosed

There is no single test that definitively diagnoses DM in a living dog. Diagnosis typically involves a combination of:

1. Clinical Signs & Neurological Exam
   A veterinarian evaluates gait abnormalities, reflexes, and hind limb strength.

2. Excluding Other Causes
   Imaging tests (such as X-rays, MRI, or CT) and spinal fluid analysis are used to rule out other causes of spinal cord dysfunction such as intervertebral disc disease or tumors. 

3. Genetic Testing
   DNA testing for the SOD1 mutation is available. A dog with two copies of the mutated gene has a higher risk of developing clinical DM. However, a positive genetic test doesn’t confirm the disease, and a negative test doesn’t entirely rule it out. Genetic results should always be interpreted in the context of clinical signs and other diagnostics. 

4. Diagnosis of Exclusion
   Because other treatable conditions can mimic DM, thorough testing is necessary before making this presumptive diagnosis. 

Treatment & Management

There is currently no cure for degenerative myelopathy, and no therapy has been proven to stop or reverse the disease’s progression. However, supportive care can improve quality of life and may help maintain mobility longer:

Supportive Therapies

• Physical therapy: Regular controlled exercise, range-of-motion exercises, strength training, and hydrotherapy (water therapy) help preserve muscle mass and mobility. 

• Mobility aids: Harnesses, slings, and dog carts can assist with walking and reduce strain on weakened limbs. 

• Home care: Soft bedding, padded surfaces, and anti-slip flooring reduce risk of injury. Owners often need to manage hygiene for dogs that become incontinent. 

Prognosis

DM is ultimately fatal. Most dogs become non-ambulatory or severely disabled within 6–24 months of symptom onset, although careful management and physical therapy may extend mobility and life quality. 

Occurrence in Bouvier des Flandres

Unlike some breeds with well-documented risk, data on degenerative myelopathy in the Bouvier des Flandres is limited. However:

• According to breed health resources, degenerative myelopathy is listed among genetic disease markers identified for Bouviers alongside conditions such as exercise-induced collapse and bobtail syndrome, indicating that the disease can occur in the breed and has been recognized by breed health organizations. 

• The SOD1 gene mutation associated with DM has been documented across many breeds, which suggests that virtually any breed, including the Bouvier, could carry the mutation and be at risk — although breed-specific prevalence is not as well characterized as it is for German Shepherds or Corgis. 

• According to the OFA Bouvier des Flandres Health Survey one bouvier has been diagnosed with DM.  Also while researching DNA to find  a genetic marker for glaucoma in Bouvier’s the University of Missouri  found the SOD1 gene in it’s bouvier sample. 

Because of this, responsible breeders and owners of Bouvier des Flandres may consider genetic screening for the SOD1 mutation as part of health testing, especially in lines with a history of neurological symptoms. Discussing breed-specific health panels with your veterinarian or a canine genetic counselor can provide better insight. 

Summary

Canine degenerative myelopathy is a progressive, neurodegenerative disease most often affecting older, large breed dogs. It begins with hind limb weakness and coordination problems, eventually leading to paralysis. Diagnosis is presumptive and involves ruling out other causes. While there’s no cure, supportive care — primarily physical therapy and mobility assistance — can improve comfort and extend functionality. Although DM is best documented in breeds like German Shepherds and Corgis, genetic markers and breed health data indicate it can occur in Bouvier des Flandres, and genetic testing may help assess risk. 

Canine Degenerative Myelopathy (CDM) Articles/Helpful Links:

https://www.akcchf.org/new-research/studying-potential-treatments/