Degenerative Myelopathy
A progressive spinal cord disease similar to ALS in humans; painless but debilitating.
What is Degenerative Myelopathy?
Degenerative myelopathy (DM) is a progressive degeneration of the spinal cord, most commonly starting in the thoracic region. It is not painful, but causes progressive loss of coordination and eventual paralysis of the hindquarters. There is a strong genetic component (SOD1 mutation).
Common signs and symptoms
Signs vary between dogs and can be subtle at first. Watch for the following, especially if several appear together or persist for more than a few days:
- Scuffing or wearing of the outer toenails
- Swaying gait in the hindquarters
- Crossing over of the hind legs when walking
- Difficulty rising from a lying position
- Progressive weakness with preserved appetite and alertness
- Eventually incontinence and inability to walk
Risk factors
Certain dogs are more predisposed. Understanding risk helps you screen earlier and act sooner.
- German Shepherd, Boxer, Corgi, Chesapeake Bay Retriever, Rhodesian Ridgeback
- Age 8+
- SOD1 gene mutation (DNA testable)
When to see a vet
Use this as general triage guidance, not a substitute for veterinary advice.
- Book a routine appointment if: any progressive hind-end weakness in a large-breed senior dog — DM is a diagnosis of exclusion, so ruling out treatable causes matters.
- Seek urgent care if: sudden loss of function should be worked up for other causes like IVDD, which may be surgically treatable.
Diagnosis and management
Diagnosis is presumptive and confirmed on postmortem exam, but MRI and DNA testing support the picture. There is no cure, but consistent physical therapy meaningfully slows progression and maintains quality of life. Assistive devices like slings and wheelchairs (carts) can extend comfortable mobility by many months.