What are the causes of a positive Romberg sign?

Causes of a Positive Romberg Sign

A positive Romberg sign indicates dysfunction of the dorsal column proprioceptive pathways of the spinal cord, not cerebellar disease, and requires systematic evaluation for structural spinal cord lesions, peripheral sensory neuropathies, and metabolic causes—particularly vitamin B12 deficiency. 1

Neurophysiological Basis

• The Romberg test specifically evaluates dorsal column function, which carries proprioceptive information from the periphery to the brain 1
• A positive test occurs when patients lose balance significantly only with eyes closed, demonstrating reliance on visual compensation for lost proprioception 1, 2
• This distinguishes sensory ataxia from cerebellar ataxia, where instability persists regardless of eye position 1, 2

Primary Etiologic Categories

Spinal Cord Pathology (Dorsal Column Lesions)

• Subacute combined degeneration from vitamin B12 deficiency is a critical reversible cause that must be identified early 1
• Copper deficiency myelopathy mimics B12 deficiency but requires distinct treatment 1
• Cervical myelopathy from spinal cord compression shows positive Romberg in 74.5% of cases 3
• Multiple sclerosis and other demyelinating diseases affecting posterior columns 1
• Spinal cord infarction, particularly affecting posterior spinal artery distribution 1
• Tabes dorsalis (neurosyphilis) was historically the classic cause described by Romberg 4
• HIV-associated myelopathy 1
• Transverse myelitis 1

Peripheral Sensory Neuropathies

• Diabetic polyneuropathy causing large-fiber sensory loss 1
• Chronic inflammatory demyelinating polyneuropathy (CIDP) 1
• Guillain-Barré syndrome, particularly sensory variants 1
• Chemotherapy-induced peripheral neuropathy (platinum agents, taxanes, vinca alkaloids) 1
• Medication-induced neuropathy (metronidazole, isoniazid) 1
• Hereditary sensory neuropathies 1
• Lyme disease with peripheral nerve involvement 1

Metabolic and Nutritional Causes

• Vitamin B12 deficiency (most important reversible cause) 1
• Copper deficiency 1
• Hypothyroidism 1
• Heavy metal toxicity (lead, arsenic, mercury) 1

Infectious Etiologies

• Neurosyphilis (tabes dorsalis) 1
• HIV myelopathy 1
• Lyme disease 1

Neoplastic and Paraneoplastic

• Paraneoplastic sensory neuronopathy 1
• Spinal cord compression from tumor 1
• Leptomeningeal carcinomatosis 1

Critical Distinction: Vestibular vs. Sensory Ataxia

• Vestibular dysfunction can produce instability that worsens on compliant surfaces but is fundamentally different from a true positive Romberg 5
• Vestibular ataxia presents with nystagmus, vertigo, and instability that may worsen with eye closure but lacks the dramatic proprioceptive loss 1
• Standing on foam with eyes closed tests vestibular function more than proprioception 5

Common Pitfalls to Avoid

• Do not attribute a positive Romberg to cerebellar disease—cerebellar ataxia produces instability with eyes open and closed (Romberg negative) 1, 2
• Do not delay vitamin B12 assessment—subacute combined degeneration progresses rapidly but reverses with early treatment 1
• Do not overlook copper deficiency—it increasingly mimics B12 deficiency and requires separate evaluation 1
• Do not use CT instead of MRI—CT lacks sensitivity for spinal cord and posterior fossa lesions 1
• Do not forget medication history—many drugs cause sensory neuropathy 1

Clinical Context Considerations

Acute Onset (Hours to Days)

• Prioritize spinal cord stroke, acute transverse myelitis, or Guillain-Barré syndrome 1
• Urgent MRI of brain and spine is mandatory 1

Subacute Onset (Weeks to Months)

• Focus on nutritional deficiencies (B12, copper), inflammatory disorders, and infections 1
• This timeframe is classic for subacute combined degeneration 1

Chronic Progressive Course

• Consider hereditary neuropathies, paraneoplastic syndromes, or degenerative conditions 1
• Cervical myelopathy often presents insidiously over months to years 3

Enhanced Sensitivity: Walking Romberg Test

• The walking Romberg test (walking 5 meters with eyes closed) detects proprioceptive deficits in 74.5% of cervical myelopathy patients versus only 34% with traditional standing Romberg 3
• Swaying, instability, or inability to complete the walk with eyes closed indicates a positive test 3
• This modification is more sensitive for detecting clinically significant myelopathy 3

Special Populations

Hepatic Encephalopathy

• While hepatic encephalopathy produces motor abnormalities including hypertonia and hyperreflexia, a positive Babinski sign can occur 6
• However, hepatic encephalopathy does not typically cause a true positive Romberg sign as it does not primarily affect dorsal column proprioception 6