Diagnosis of cervical spondylotic myelopathy
The diagnosis of cervical myelopathy depends on the patient's history and the physical findings described above. It may then be confirmed by radiologic imaging, such as an MRI scan of the cervical spine demonstrating overt spinal cord and nerve root compression (see Figure 1 [5]).
Diagnostic studies to diagnose cervical spondylotic myelopathy
Additional diagnostic studies often performed include:
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In certain instances (especially when the details of bone anatomy must be seen clearly), a cervical myelogram and post-myelogram CT scan may aid in determination of the anatomy associated with nerve root and spinal cord compression.
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Advanced cases may show abnormal signal within the spinal cord on MRI imaging and/or atrophy of the spinal cord due to nerve cell loss. In such cases, referred to as "myelomalacia," surgical outcomes may not be as promising.
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Flexion/extension cervical spine films to rule out translational instability of the cervical vertebral bodies, which can influence the choice of treatment.
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Somatosensory evoked potentials (SSEPs) or motor evoked potentials (MEPs) to provide a measure of the electrical conductivity of the spinal cord across the compressed segments. Such testing may also be performed as a baseline in anticipation of monitoring of the spinal cord during surgery itself.
Differential diagnosis of cervical spondylotic myelopathy
To arrive at an accurate diagnosis, it is critical for the physician to consider other disorders that have similar symptoms as cervical spondylotic myelopathy (a "differential diagnosis"). Other conditions associated with neck pain and arm pain, motor-sensory-reflex changes, and signs of spinal cord dysfunction include:
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Progressive forms of multiple sclerosis
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Amyotrophic lateral sclerosis (Lou Gehrig's disease)
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Hereditary spastic paraplegia
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Subacute combined degeneration of the spinal cord associated with vitamin B12 deficiency
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Certain spinal cord tumors
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Combined system disease