Lhermitte sign test: How to perform, interpret, and act on findings

Found our content helpful?

Key takeaways

The Lhermitte sign test is performed by flexing the patient’s neck forward, either passively or with the patient leading.

A positive result is a brief electric shock traveling from the neck down the spine and into the limbs.

The finding points to posterior column irritation or demyelination, most commonly from multiple sclerosis or cervical myelopathy.

Cervical spondylosis, B12 deficiency, radiation myelopathy, and cord compression all produce the same sensation, so imaging decides the cause.

Treatment targets the underlying condition, and the neurological deficit sets how urgently the patient needs referral.

The Lhermitte sign test is a clinical assessment that provokes a brief, electric shock-like sensation down the spine when the patient flexes their neck forward.

A positive result points to irritation or demyelination of the posterior columns of the cervical spinal cord.

According to StatPearls (NCBI), it is one of the most recognizable signs in neurology. It is associated most often with multiple sclerosis (MS) and cervical myelopathy.

This guide covers how to perform and interpret the test, what causes a positive result, how to document it, and when to refer. It is written for clinicians and clinical learners.

What Lhermitte’s sign is and why it matters

Lhermitte’s sign is a transient, electric shock-like paresthesia that travels from the neck down the spine, often reaching the arms or legs. Forward neck flexion provokes it.

It is also called Lhermitte’s phenomenon or the barber chair phenomenon. The second name comes from the sensation patients describe when they recline into a barber’s chair.

The finding works as both a sign and a symptom. Clinicians elicit it during examination, and patients report it spontaneously when they look down. Some sources reserve the word sign for the provoked version, though the literature uses both terms interchangeably.

A positive result is a neurological red flag that calls for further investigation. On its own it names no diagnosis. Clinicians in neurology, primary care, and physical therapy practices need to separate it from other cervical spine signs and act on it.

Why neck flexion triggers the sensation

Neck flexion mechanically stretches the posterior columns, also called the dorsal columns, of the cervical spinal cord. Where those columns are demyelinated or structurally compromised, the stretch triggers ectopic electrical impulses in the affected axons. Neurologists call this ephaptic transmission.

Myelin normally insulates axons and prevents cross-talk between nerve fibers. Once the myelin sheath is damaged, adjacent axons fire spontaneously and propagate signals in unusual directions. That produces the characteristic electric sensation.

The finding reflects posterior column dysfunction directly. That is why the sensation usually radiates caudally, from the neck toward the limbs, rather than staying local at the cervical level.

How to perform the Lhermitte sign test

The test has two accepted variants. In passive elicitation the clinician guides the movement, and in active elicitation the patient moves their own neck. Both are valid, and passive is preferred where cervical instability is not suspected.

1. Position the patient. Seat the patient upright on an examination couch with the neck in a neutral position.
2. Explain the procedure. Tell the patient you will move their chin toward their chest, or ask them to do it. Ask them to report any electric shock, tingling, or radiating sensation immediately.
3. Perform cervical flexion. For passive elicitation, rest one hand on the occiput and guide the chin slowly toward the chest. For active elicitation, ask the patient to flex their neck forward on their own.
4. Observe and document. A positive test is any report of a brief, electric shock-like sensation radiating down the spine or into the limbs during or just after flexion.
5. Assess duration and distribution. The sensation is usually transient and lasts under a few seconds. Record the radiation pattern, the onset, and whether it reaches the arms, the legs, or both.

Contraindication: do not perform passive cervical flexion where cervical instability is known or suspected. That includes atlantoaxial subluxation in rheumatoid arthritis, a trauma history, and known ligamentous laxity. Image first, then examine.

How to interpret a positive result

A positive result does not confirm a diagnosis. It confirms posterior column involvement at or above the cervical cord, which narrows the differential considerably. Further investigation still decides the cause.

Three interpretation points matter at the bedside:

• True positive: an electric shock sensation radiating caudally during or just after neck flexion, transient in duration.
• False positive: patients who are anxious or hypervigilant may report vague paresthesias that do not radiate consistently. Match the description against the classic pattern before you record a positive.
• Directionality: the sensation travels from neck to limbs, not locally at the neck. Local cervical pain on flexion without radiation is a negative test.

Diagnostic accuracy varies by population. In multiple sclerosis cohorts, sensitivity for cervical cord demyelination is reported between 9% and 41%. A negative test therefore does not rule the condition out.

Specificity is higher, which makes a positive result more informative. Interpret it in clinical context rather than in isolation, and compare it against the patient’s earlier examinations where you have them.

What causes a positive result

Several conditions disrupt the posterior columns and produce the same sensation. Multiple sclerosis and cervical myelopathy account for most cases, and the wider differential runs from vitamin deficiency to radiation injury.

Lhermitte’s sign in multiple sclerosis

The association with multiple sclerosis carries the most clinical weight. The sign can be an early presenting symptom, sometimes appearing before a formal MS diagnosis. In this population it reflects active cervical cord demyelination and often tracks relapse activity.

Heat can worsen the sensation in patients with MS. That overlaps with Uhthoff’s phenomenon, where a raised body temperature temporarily worsens neurological symptoms through impaired conduction in demyelinated fibers. The distinction matters when you counsel patients about exercise and bathing.

Cervical myelopathy and the compressive causes

Cervical spondylosis and disc herniation compress the posterior columns mechanically rather than demyelinating them. The clinical picture can look identical to MS-related Lhermitte’s, which makes imaging essential.

MRI with and without contrast is the investigation of choice for separating structural compression from inflammatory demyelination. Older patients with degenerative cervical spine changes are the group to watch.

How Lhermitte’s sign differs from other cervical tests

Lhermitte’s sign shares clinical territory with several other examination findings. Knowing the differences keeps the workup targeted and stops any single test from carrying too much weight.

The direction of travel is the clearest separator. Lhermitte’s radiates caudally from the neck into the limbs, while Spurling’s test produces ipsilateral radicular arm pain with no caudal radiation. The modified Romberg test adds a proprioceptive read on the same posterior columns.

Running all three in one session gives a far richer picture of the level and nature of cord involvement. That matters most after neck trauma, where a single positive finding is easy to over-read.

The workup after a positive test

A positive result starts the workup rather than ending it. What follows decides whether the cause is demyelinating, structural, metabolic, or vascular, and whether the patient needs urgent intervention.

The path from cervical flexion to a referral decision runs through four stages.

1. MRI cervical spine with and without gadolinium contrast, as the first-line investigation. Contrast enhances active MS lesions, and T2 signal change identifies structural cord compression.
2. Brain MRI where MS is clinically suspected. Look for periventricular and juxtacortical white matter lesions consistent with demyelinating disease under the McDonald criteria.
3. Blood tests: serum B12, methylmalonic acid, and folate to exclude subacute combined degeneration, plus a full blood count for macrocytic anemia.
4. Full neurological examination: Babinski, Hoffmann’s, Romberg, vibration sense, and proprioception, to quantify posterior column and upper motor neuron involvement.
5. Referral: neurology for suspected MS or unexplained myelopathy. Neurosurgery where MRI shows significant cord compression, and hematology where B12 deficiency is confirmed with neurological involvement.

Record the reflex findings from step four in the same place as the sign itself. A structured deep tendon reflex exam keeps the biceps, triceps, and lower limb responses beside the Lhermitte’s entry, which is what the neurologist reads first.

Treatment and management by underlying cause

Treatment is always directed at the underlying condition. No intervention removes the sign on its own, though targeted management often reduces how often it fires and how hard it hits.

• Multiple sclerosis: disease-modifying therapies reduce relapse frequency and can lower how often Lhermitte’s appears during a relapse. Carbamazepine and gabapentin have been used clinically for symptom relief, though the primary evidence is limited. Prescribing should follow specialist guidance. Cool environments and cool showers reduce provocation, because of the Uhthoff overlap.
• Cervical myelopathy: surgical decompression, such as anterior cervical discectomy or laminoplasty, is indicated where MRI confirms cord compression with neurological deficit. Neurosurgery makes that call on imaging, symptom severity, and rate of progression.
• B12 deficiency and subacute combined degeneration: intramuscular B12 replacement is the treatment. The sign may resolve or improve, depending on how long the deficiency ran and how much axonal loss occurred.
• Radiation myelopathy: no curative treatment exists, so management is supportive, with rehabilitation and symptom monitoring. Involve the oncology team, given the complexity of late radiation effects.

A patient waiting for a neurology appointment can deteriorate with nobody watching. Build a follow-up touchpoint between the formal appointments, so symptom progression is recorded as it happens rather than reconstructed from memory months later.

How to document the finding in clinical notes

The wording of the entry carries the referral, and later it carries the medico-legal record. A reviewer reading the note a year afterward needs the detail the neurologist needed on the day. The framework below sets that out.

In a SOAP note or clinical record, a positive finding should carry:

• Elicitation method: passive and clinician-guided, or active and patient-performed.
• Response description: “electric shock-like sensation radiating from the cervical region into the bilateral lower limbs”, or whichever distribution applies.
• Onset and duration: immediate on flexion, transient, under five seconds.
• Associated findings: any concurrent upper motor neuron signs such as Babinski or Hoffmann’s, plus vibration sense deficit or proprioceptive loss.
• Interpretation: “positive Lhermitte’s sign consistent with posterior column involvement at the cervical level, MRI cervical spine requested”.

Name the dermatomal level in that entry wherever the examination supports it. “Into the right arm” and “C6 distribution” are read very differently by a neurologist.

Negative findings deserve the same care. Write “Lhermitte’s sign not elicited on passive cervical flexion, no electric or radiating sensation reported”. A documented negative carries as much weight as a positive when you track progression over time.

When to refer urgently

An isolated positive sign rarely needs an ambulance, and the same sign with progressive weakness does. The table below separates the emergency from the routine, so the referral matches the deficit in front of you.

Making the referral decision is the straightforward part. Chasing it is where patients get lost. Someone can wait weeks for imaging while the referral sits unacknowledged, so track the acknowledgment rather than assuming it.

How Pabau keeps neurological findings in the client record

A positive Lhermitte’s sign usually lands in a free-text note, and the detail is retyped into the referral letter later. The elicitation method and the radiation pattern drop out somewhere between the two. The neurologist then reads “positive Lhermitte’s” with no supporting detail.

Pabau stores the examination as a structured note against the client record. The finding you documented in March sits beside the one you documented in September. A change in the radiation pattern is then visible rather than remembered.

Pabau Scribe, our AI scribe, drafts the note from the consultation itself. The elicitation method and the associated findings land in the record while the examination is fresh, and referral letters pull from that same note.

Follow-up tasks and recalls run off the same timeline, so a patient waiting on an MRI stays in view. The practice finds out about a deterioration from its own diary rather than from a complaint.

Keep examination findings and referrals in one record

Pabau stores neurological examination findings against the client record and carries them into referral letters, so the detail you documented reaches the neurologist intact.

Book a demo

Conclusion

The Lhermitte sign test costs ten seconds and a hand on the occiput, and it changes what you do next. A positive result narrows the field to posterior column pathology and sets the investigation in motion.

The judgment worth keeping is that the sign does not grade severity on its own. Sensitivity is low enough that a negative test changes little, and the urgency comes from the deficit sitting beside the sign.

Write the finding down the way you would want to read it in someone else’s referral letter. Book a demo to see how Pabau keeps neurological examination findings and referral follow-up in one client record.

Continue your research

Need the radiculopathy side of the differential? Spurling’s test covers the technique and interpretation for cervical nerve root compression.

Assessing proprioception alongside the cord? Modified Romberg test explains how to score postural sway and what a positive result localizes.

Checking cervical endurance after a neck complaint? Cervical extensor endurance test gives the hold times and the normative values to compare against.

Running a physical therapy or musculoskeletal practice? Mandatory compliance for physiotherapy clinics outlines the documentation and regulatory requirements for neurological and MSK assessments.

Testing the deep neck flexors after a cervical complaint? Cranio-cervical flexion test sets out the pressure stages and a scoring sheet to record them on.

Frequently asked questions