Recognising the final stages of Degenerative Myelopathy (DM) in dogs 

Introduction

For owners of dogs with chronic and debilitating conditions such as degenerative myelopathy, knowing that things are only going to get worse can cast a real shadow over family life. Understanding the disease process may help some people deal with the situation. For others, they may not wish to know the ins and outs. But no matter the approach, it is vital that all owners appreciate when the time has come, when euthanasia is the right option for their pet.

Table of Contents

• What is Degenerative Myelopathy in dogs?
• Breeds Most Affected by Degenerative Myelopathy
• General Symptoms of Degenerative Myelopathy in Dogs
• Stages of Degenerative Myelopathy in Dogs
• Diagnosis
• Treatment
• Lifespan of Dogs with Degenerative Myelopathy
• Emergency Conditions & Complications
• Warning Signs of Advancing Degenerative Myelopathy in Dogs
• When should euthanasia be considered for a dog with Degenerative Myelopathy?
• FAQs

What Is Degenerative Myelopathy in Dogs?

Canine degenerative myelopathy (CDM or DM) was previously known as chronic degenerative radiculomyelopathy (CDRM) and is a progressive degenerative spinal cord disease which affects middle-aged to older dogs. It is an inherited condition and, although it is not painful, there is no cure, and it will eventually cause a severe and highly distressing paralysis, ultimately resulting in death.

Breeds Most Affected by Degenerative Myelopathy

Because degenerative myelopathy is a genetic condition, linked to a genetic mutation of the SOD-1 gene, it has a strong breed predilection, mainly for larger breed dogs. Degenerative myelopathy has been observed in more than 24 different breeds to date with certain breeds being particularly susceptible. Among the breeds commonly affected by DM are:

• German Shepherds and their crosses
• Siberian Huskies
• Collies

Additionally, several other breeds have been identified as being at risk of developing DM including:

• Bernese Mountain Dogs
• Boxers
• Chesapeake Bay Retrievers
• Golden Retrievers
• Kerry Blue Terriers
• Miniature Poodles
• Nova Scotia Duck Tolling Retrievers
• Pugs
• Rhodesian Ridgebacks
• Standard Poodles
• Pembroke Corgis
• Cardigan Welsh Corgis
• Wirehaired Fox Terriers.

General Symptoms of Degenerative Myelopathy in Dogs

The expected symptoms of degenerative myelopathy can all be related to the deterioration in nerve function, initially in the hind legs then as the disease progresses, the symptoms can become apparent in the forelimbs. Eventually the disease can also affect the nerves that control breathing and toileting.

Disease progression can vary, but the majority of dogs are euthanised on welfare grounds within 6-18 months of the symptoms first becoming apparent. Even though there is no pain involved, the impact on their quality of life can be drastic.

Stages of Degenerative Myelopathy in Dogs

Stage 1: Early Signs of DM

First seen to affect the hind limbs and are often put down to simply ‘old age’:

• Increased difficulty in standing up after lying down
• Swaying of hips when walking or standing
• Crossing of hind legs when walking or standing
• Abnormal gait or walking pattern
• Hind legs collapsing or appearing wobbly

Stage 2: Progression of Hind Limb Symptoms

As the disease progresses, not only do the original symptoms get worse, but new ones can develop:

• Severe hind leg weakness or paralysis
• Inability to stand or walk unassisted
• Decreased or absent spinal reflexes in hind legs
• Loss of muscle mass in hind limbs
• Impaired tail function
• Pressure sores

Stage 3: Symptoms Extend to Front Legs

Not only will the disease ‘extend’ up the body, but it can start to affect other body systems such as the bladder.

• Inability to coordinate or move muscles of rear limbs
• Struggles to push up or walk on front legs
• Severe muscle loss in rear legs
• Faecal or urinary incontinence leading to urine scald
• Absence of spinal reflexes in hind limbs

Stage 4: Final Stages of Degenerative Myelopathy

Once a dog reaches the final stages of degenerative myelopathy, their welfare is likely to be extremely compromised.

• Complete paralysis of all four legs
• Loss of all spinal reflexes
• Severe muscle loss throughout the body
• Difficulty breathing, changes in voice, or swallowing difficulties, gradually progressing to respiratory collapse
• Disorientation and neurological changes
• Bed sores (pressure sores) from constantly lying down

Along with all these physical symptoms that we can see, we must also recognise that there will often be an impact on a dog’s mental health too, as they struggle to cope with the changes. These can be seen at any stage but will tend to worsen along with the physical symptoms.

• Anxiety or frustration
• Changes in attitude or temperament
• Decreased eating or drinking
• Irritability or aggression

Diagnosis

Unfortunately, there isn’t currently a test for diagnosing canine degenerative myelopathy. Diagnosis is most commonly made by ruling out other conditions that can have similar symptoms. These could include a ‘slipped disc’ or a tumour on the spinal cord.

If a patient presents with early symptoms, a vet is likely to suggest spinal x-rays initially but if nothing is found and the symptoms progress, an MRI scan is likely to be recommended.

DNA tests

While it is true that affected dogs all have defective SOD1 genes, there are also environmental factors. If a dog undergoes genetic testing and is found to carry the mutated gene responsible for DM, there is no certainty that they will go on to develop the disease.

Canine Degenerative Myelopathy Treatment

There is no treatment available to cure or slow down degenerative myelopathy. Care of patients revolves around management strategies and how to support them mentally and physically.

Management Strategies and Supportive Care

It’s important that affected dogs stay as fit and healthy as possible and aren’t allowed to get overweight. As their mobility decreases, they may need help at home by way of ramps or steps to get up to different levels and, ultimately, owners may need to use a sling to support their dog to stand and get around.

Because they tend to lose the ability to place their feet properly, their nails and toes can easily get scuffed. To help with this, they can wear special boots to protect their feet and putting rugs or carpets down can help them maintain grip on slippery surfaces.

Therapies and Exercises to Maintain Mobility

Although no medications have ever been proven to help with DM, physical therapies such as physiotherapy or hydrotherapy can be beneficial. These will help to maintain muscle mass, keep them fit, and also provide mental stimulation for the dog.

Lifespan of Dogs with Degenerative Myelopathy

Average Survival Time After Diagnosis

Degenerative myelopathy is not an immediately fatal condition in itself, unless it is left to progress to such a severe level that the breathing is impaired, or the dog is unable to eat or drink. Thankfully, before they get to that point, many owners will opt for euthanasia. The speed of progression of symptoms can vary, but from the start of signs to the point of incontinence or inability to walk is typically 6-18 months. This is when most owners would make the call to euthanise.

Factors Affecting Longevity and Quality of Life

The main factor affecting longevity is how the animal is coping with the symptoms and how fast they are progressing. If their quality of life is beginning to suffer, either by way of rapid progression, severe symptoms or poor ability to cope, it’s time to discuss the worsening situation with their vet.

Monitoring Disease Progression

As with diagnosis, there is no specific test that can be utilised to monitor the progression of the disease. Instead, we rely on the clinical symptoms and how well the animal is coping with them. It is important to track the progression with regular check-ups, so there is a record to look back on, helping to put the dog’s situation into perspective.

Emergency Conditions & Complications

Identifying and managing urinary tract infections and bed sores

Because of the inability of the patient to control their urination, they can suffer with both urine overflow and urine retention, and so tend to have a higher incidence of urinary tract infections and urine scald. These must be managed with veterinary intervention such as antibiotics and pain relief.

Due to the weakness caused by degenerative myelopathy, dogs will also spend a lot of their later lives lying down. This can cause painful bed sores and ulcers, in a similar way to bed-bound human patients. Managing these requires the use of well-padded bedding, dressings as required, and pain relief.

There are unlikely to be many emergency situations when caring for a dog with DM but potentially a trauma from a fall or severe impairment to breathing later on in the disease could require urgent treatment.

Warning Signs of Advancing Degenerative Myelopathy in Dogs

As mentioned at the start of this article, it is vital that owners of dogs with degenerative myelopathy recognise the advancing symptoms and when an animal’s quality of life may suffer. The warning signs to look for include:

• Progressive hind limb weakness and paralysis
• Loss of bowel and bladder control
• Muscle atrophy
• Difficulty breathing

When should euthanasia be considered for a dog with degenerative myelopathy?

Just because a dog has been living with DM for a long time, it doesn’t make it any easier for the owner to make that final decision about euthanising their pet.

Signs a Dog With DM Is Nearing the End

Owners can familiarise themselves with the signs to look for, in the stages above, which show that the disease is worsening. The point that euthanasia should be considered will vary for different dogs and their families, but deteriorating mobility and incontinence are significant markers. What can be particularly distressing for both the dog and their owner is when they begin to struggle with their breathing.

Assessing Your Dog’s Quality of Life

Quality of life is largely a subjective matter but will have a scaffolding of objective measures like worsening symptoms. Owners should also look for changes in their pet’s routine, going off food and not wanting to take part in things they used to enjoy such as playing, going for a walk or simply just interacting with their owners. We have a helpful quality of life questionnaire on our website which can help owners with their decisions.

Having Open Discussions with Your Veterinarian

At any point along their DM journey, owners should always feel they can have honest and open discussions with their veterinarian. For any condition, it can be very helpful to have conversations with a professional – they can look at the situation from a medical and objective point of view, whereas an owner will always be emotionally involved with their pet. Our team of Care Coordinators are also available for no obligation advice over the phone.

FAQs

How long can a dog with degenerative myelopathy live with appropriate treatment?

Some research suggests 6-12 months, others say 12-18 months, but with the end point typically being euthanasia, the lifespan will vary depending on various owner and dog factors.

What are the signs of urinary tract infections in dogs with DM?

The signs of a urinary tract infection include an increased frequency of urination, only passing small quantities of urine, blood in the urine and pain on urination.

When should euthanasia be considered for a dog with degenerative myelopathy?

The timing of euthanasia will depend on a number of factors – the severity of the symptoms, whether the owner is capable of managing the dog’s symptoms and the overall impact of the disease on the dog’s quality of life.