Distinguishing Myelopathy from Radiculopathy
Myelopathy involves spinal cord compression causing bilateral symptoms, gait disturbance, and loss of fine motor skills, while radiculopathy involves nerve root compression causing unilateral dermatomal pain and sensory/motor deficits in a specific nerve distribution. 1, 2
Anatomical Level of Pathology
Myelopathy:
- Compression occurs at the spinal cord level within the spinal canal 3
- Results in damage to ascending and descending white matter tracts and gray matter 4
- Can cause symptoms both above and below the level of compression 5
Radiculopathy:
- Compression occurs at the nerve root level, typically in the neural foramen 4, 2
- Affects a single nerve root or its branches 2
- Symptoms follow a specific dermatomal distribution in the upper extremity 1
Clinical Presentation Differences
Myelopathy presents with:
- Bilateral symptoms affecting both upper and/or lower extremities 1, 6
- Loss of fine motor skills and hand dexterity (difficulty with buttons, writing) 3
- Gait disturbance and balance problems 6
- Bladder or bowel dysfunction in severe cases 1
- Hyperreflexia and pathological reflexes (Babinski sign) 3
- Progressive weakness that is typically bilateral 6
Radiculopathy presents with:
- Unilateral arm pain in a dermatomal pattern 4, 1
- "Electric" or shooting quality neuropathic pain radiating down the arm 1
- Sensory deficits confined to a specific dermatome 2
- Motor weakness in specific myotomes 2
- Diminished or absent reflexes at the affected level 1
- Symptoms typically confined to the upper extremity 1
Critical Diagnostic Red Flags
When a patient presents with progressive hand weakness and numbness, these features indicate myelopathy rather than simple radiculopathy:
- Bilateral upper extremity symptoms 1, 6
- Any lower extremity involvement (unilateral arm AND leg symptoms together) 1
- Gait disturbance or difficulty with fine motor tasks 6
- New bladder or bowel dysfunction 1
- Loss of perineal sensation 1
Natural History and Prognosis
Radiculopathy:
- 75-90% of cases resolve with conservative nonoperative therapy 4, 6, 2
- Most cases improve within 6-12 weeks 6
- Self-limiting course is the norm 2
Myelopathy:
- Does NOT typically improve spontaneously 4
- Natural history shows slow, stepwise decline in many patients 4
- Only ~30% of patients with mild-moderate myelopathy remain stable over 3 years with conservative management 4
- Severe stenosis can result in irreversible necrosis of gray and white matter 4
Combined Presentation
Important clinical caveat: Approximately 50% of patients with cervical myelopathy also have concurrent radiculopathy 7. These patients present with:
- Higher preoperative arm pain scores compared to myelopathy alone 7
- Both cord compression symptoms AND dermatomal radicular pain 7
- This combination requires recognition because it affects surgical planning 7
Imaging Approach
MRI cervical spine without contrast is the preferred imaging for both conditions 4, 1, 6:
- Superior for detecting disc herniations and nerve root compression in radiculopathy 4
- Essential for visualizing spinal cord compression and signal changes in myelopathy 4
- Must always be interpreted in combination with clinical findings due to frequent false-positives in asymptomatic individuals 4
Management Implications
Radiculopathy:
- Initial conservative management with NSAIDs, physical therapy, and activity modification 6
- Surgery considered only after 6-12 weeks of failed conservative therapy 6, 2
Myelopathy:
- Surgical decompression should be considered earlier, especially with progressive deficits 1
- Patients with severe symptoms and long duration generally do not improve without surgery 4
- Failure to decompress can result in permanent disability 3
The key distinction is that myelopathy represents a surgical urgency when progressive, while radiculopathy is typically managed conservatively with excellent outcomes. 4, 2