Degenerative Myelopathy Studies in people with a similar condition, Lou Gehrig's disease, have shown that an advanced MRI technique called diffusion tensor imaging is able to detect the microscopic changes in the spinal cord caused by this condition.
Although cervical myelopathy is determined clinically, the diagnosis requires confirmation via imaging, and MRI is the preferred modality.
How is DM diagnosed? This disease will be suspected on the basis of breed, medical history, physical examination, and diagnostic tests. X-rays and other spinal imaging techniques will rule out other problems such as hip dysplasia and chronic arthritis, most often during the initial stages of DM.
In patients with clinical myelopathy, a pancake-like gadolinium enhancement on sagittal images and a circumferential enhancement on axial images are indicative of CSM.
Hyperintense intramedullary signal at T2-weighted imaging is a common and important indicator of myelopathy at MRI (1). T2 hyperintensity can reflect many processes at the microscopic level, including edema, blood–spinal cord barrier breakdown, ischemia, myelomalacia, or cavitation (2).
14 Disorders that often mimic and coexist with DM include degenerative lumbosacral syndrome, intervertebral disc disease, spinal cord neoplasia and degenerative joint diseases such as hip dysplasia or cranial cruciate ligament rupture.
Symptoms of Myelopathy
Pain in the lower back, neck, arm or leg. Tingling, numbness or weakness. Decreased fine motor skills, balance, and coordination. Abnormal or increased reflexes in extremities.
The important thing to remember with degenerative myelopathy is that the condition itself is not painful to the dog, but is more “painful” for the owner to watch. If you have a dog with degenerative myelopathy it is important to remember that it's about the quality of your dog's life and not the quantity of the days.
Red flags are of most value when multiple exist. Anything that suggests myelopathy and these include: slow onset, neurological symptoms, difficulty walking, weak hand or foot movement, loss of bowel bladder or bowel function. Vascular signs and symptoms such as dizziness, black outs and drop attacks.
Cervical myelopathy occurs in the neck and is the most common form of myelopathy.
Cervical Myelopathy Diagnosis
To diagnose cervical myelopathy, your doctor may: Conduct a physical examination and measure your muscle strength and reflexes. Conduct further tests, including an MRI scan, an X-ray or a CT myelogram of your neck.
A blood sample may be taken to rule out metabolic causes of spinal cord dysfunction for example cobalamin deficiency and also for genetic testing for the degenerative myelopathy associated genetic mutation.
How Quickly Does Degenerative Myelopathy Progress? Unfortunately, DM tends to progress very quickly. Most dogs that have been diagnosed with degenerative myelopathy will become paraplegic within six months to a year.
This disease is not uncommon in some pure bred dogs with an overall prevalence rate of 0.19%. Although the German Shepherd Dog is the most commonly affected breed, DM has been reported in other breeds and most recently in the Pembroke Welsh Corgi (PWC).
Symptoms of Degenerative Myelopathy in Dogs
They will lose feeling in the hind limbs, which results in dragging of the paws, scuffing of the toenails and/or tops of the paws, and abnormal paw placement. Affected dogs will be wobbly and may knuckle over the paws, cross the hind limbs, or stumble while walking.
Degenerative cervical myelopathy (DCM) and multiple sclerosis (MS) are two common conditions with distinctive pathophysiology but overlapping clinical manifestations which may include myelopathy, motor/sensory disturbances, and bowel/bladder dysfunctions.
Physical examination results commonly in long tract signs such as spasticity, hyperreflexia and abnormal reflexes. Hoffmann, Babinski, and clonus are frequently tested reflexes. Someone with myelopathy has a positive Hoffman and/or Babinski and/or clonus test.
Autoimmune myelopathies are a heterogeneous group of immune-mediated spinal cord disorders with a broad differential diagnosis.
Spondylosis refers to degenerative, or age-related, changes in the spine. These changes include disc degeneration, bone spurs, and thickened ligaments. Cervical spondylotic myelopathy, therefore, is myelopathy (spinal cord damage) caused by spondylosis (degeneration) in the cervical spine (neck).
By nature, DM is a progressive condition, which means symptoms will worsen over time. In addition, each stage of DM will affect your dog's mobility differently. For example, in its earliest stages, dogs with Degenerative Myelopathy may experience only minor changes in their gait.
In its final stages, degenerative myelopathy can spread to the brain stem. This impacts cognitive function as well as the ability to breathe and swallow normally.
Diagnosis and Tests
The most common symptoms of myelopathy are not unique to this condition. They can be mistaken for other disorders.
Patients with myelopathies commonly have excessive daytime sleepiness and disturbed sleep, including reduced rapid eye movement (REM) sleep, increased need for sleep medications, snoring, and sleep-apnea syndrome.
DDD and MS are sometimes mistaken for one another, even by health care providers, as they share some symptoms and they both develop at a similar age (30s). “They were looking for lesions and found I had DDD as well,” reported one member of MyMSteam.