Management of Lhermitte Sign
The management of Lhermitte sign should focus on identifying and treating the underlying cause, as this symptom indicates cervical spinal cord pathology that requires prompt neuroimaging and specialist evaluation.
Understanding Lhermitte Sign
Lhermitte sign is characterized by:
- Electric shock-like sensations that radiate down the spine
- Typically triggered by neck flexion
- May radiate into arms and legs
- Usually brief and self-limiting episodes
- Indicates pathology affecting the dorsal columns of the cervical spinal cord
Diagnostic Approach
Initial Evaluation
- Detailed neurological examination focusing on:
- Motor strength
- Sensory function
- Deep tendon reflexes
- Gait assessment including tandem gait
- Presence of other neurological signs
Neuroimaging
- MRI of cervical spine with and without contrast is the first-line imaging study 1
- MRI of the brain should also be performed to evaluate for demyelinating diseases
- If MRI is contraindicated, CT myelography may be considered
Management Based on Underlying Etiology
Multiple Sclerosis
- Most common cause of Lhermitte sign (present in approximately 41% of MS patients) 2
- Management includes:
- Disease-modifying therapies for MS
- Symptomatic treatment with membrane stabilizers (carbamazepine, gabapentin)
- Physical therapy focusing on cervical stabilization
Cervical Spondylosis/Compression
- For compression-related Lhermitte sign:
- Cervical collar for immobilization may provide relief 3
- Physical therapy focusing on cervical stabilization
- Surgical decompression if significant cord compression is present
Radiation-Induced
- If related to prior radiation therapy:
- Symptomatic management with membrane stabilizers
- Vitamin B supplements
- Consider hyperbaric oxygen therapy in selected cases
Chemotherapy-Induced
- If related to neurotoxic chemotherapy (especially cisplatin):
- Consider dose modification or discontinuation of the offending agent
- Vitamin B supplementation
- Membrane stabilizers for symptomatic relief
Spinal Cord Tumors
- Intrinsic or extrinsic tumors can present with Lhermitte sign 4
- Management includes:
- Neurosurgical consultation for potential resection
- Radiation therapy for appropriate tumors
- Regular follow-up imaging to monitor progression
Traumatic
- If post-traumatic in origin 5:
- Cervical collar for stabilization
- Physical therapy
- Pain management with membrane stabilizers
Symptomatic Management
For persistent symptoms regardless of etiology:
- Membrane-stabilizing medications:
- Carbamazepine (200-400 mg twice daily)
- Gabapentin (300-1200 mg three times daily)
- Pregabalin (75-150 mg twice daily)
- Physical therapy focusing on:
- Cervical stabilization exercises
- Nerve gliding techniques
- Posture correction
Special Considerations
Reverse Lhermitte Sign
- Electric shock sensations triggered by neck extension rather than flexion
- Often indicates extrinsic compression of the cervical cord 3
- Management typically focuses on cervical immobilization rather than medication
Warning Signs Requiring Urgent Evaluation
- Progressive neurological deficits
- Bowel or bladder dysfunction
- Significant gait disturbance
- Severe or persistent pain
- Signs of myelopathy (hyperreflexia, Babinski sign)
Follow-up Recommendations
- Regular neurological assessment to monitor for disease progression
- Repeat imaging based on clinical course and underlying etiology
- If no clear etiology is found initially, consider follow-up MRI in 3-6 months
Conclusion
Lhermitte sign is an important neurological finding that warrants thorough investigation. While the symptom itself may be managed symptomatically, identifying and treating the underlying cause is essential for preventing progression of potential serious neurological conditions.