neurology Neurology (from , "string, nerve" and the suffix wikt:-logia, -logia, "study of") is the branch of specialty (medicine) , medicine dealing with the diagnosis and treatment of all categories of conditions and disease involving the nervous syst ...

, Lhermitte phenomenon, also called the barber chair phenomenon, is an uncomfortable "electrical" sensation that runs down the back and into the limbs. The sensation can feel like it goes up or down the

spine Spine or spinal may refer to: Science Biology * Spinal column, also known as the backbone * Dendritic spine, a small membranous protrusion from a neuron's dendrite * Thorns, spines, and prickles, needle-like structures in plants * Spine (zoology), ...

. It is painful for some, although others might simply feel strange sensations. In many people, it is elicited by bending the head forward. It can also be evoked when a practitioner pounds on the

cervical spine In tetrapods, cervical vertebrae (: vertebra) are the vertebrae of the neck, immediately below the skull. Truncal vertebrae (divided into thoracic and lumbar vertebrae in mammals) lie caudal (toward the tail) of cervical vertebrae. In sauro ...

while the neck is flexed; this is caused by involvement of the posterior columns. Lhermitte phenomenon is named after the French neurologist

Jean Lhermitte Jacques Jean Lhermitte () (20 January 1877 – 24 January 1959) was a French neurology, neurologist and Neuropsychiatry, neuropsychiatrist. Early life and education Lhermitte was born in Mont-Saint-Père, Aisne, son of Léon Augustin Lhermit ...

. __TOC__

Associated conditions

The sign suggests a lesion or compression of the upper cervical spinal cord or lower brainstem—usually dorsal columns of the cervical cord or caudal

medulla Medulla (Latin for "marrow") or medullary may refer to: Science * Medulla oblongata, a part of the brain stem * Renal medulla, a part of the kidney * Adrenal medulla, a part of the adrenal gland * Medulla of ovary, a stroma in the center of the ...

. Although often considered a classic finding in

multiple sclerosis Multiple sclerosis (MS) is an autoimmune disease resulting in damage to myelinthe insulating covers of nerve cellsin the brain and spinal cord. As a demyelinating disease, MS disrupts the nervous system's ability to Action potential, transmit ...

, it can be caused by a number of conditions, including

transverse myelitis Transverse myelitis (TM) is a rare neurological condition wherein the spinal cord is Inflammation, inflamed. The adjective ''wikt:transverse#Adjective, transverse'' implies that the spinal inflammation (myelitis) extends horizontally throughout ...

Behçet disease Behçet is a Turkish name and may refer to: Given name * Behçet Cantürk, Turkish mob boss * Behçet Necatigil, Turkish author and poet * Behçet Uz, Turkish politician and doctor Surname * Hulusi Behçet, Turkish dermatologist and scientist Oth ...

osteogenesis imperfecta Osteogenesis imperfecta (; OI), colloquially known as brittle bone disease, is a group of genetic disorders that all result in bones that bone fracture, break easily. The range of symptoms—on the skeleton as well as on the body's other Or ...

, trauma, radiation

myelopathy Myelopathy describes any neurologic deficit related to the spinal cord. When due to trauma, myelopathy is known as (acute) spinal cord injury. When inflammatory, it is known as myelitis. Disease that is vascular in nature is known as vascular ...

vitamin B12 Vitamin B12, also known as cobalamin, is a water-soluble vitamin involved in metabolism. One of eight B vitamins, it serves as a vital cofactor (biochemistry), cofactor in DNA synthesis and both fatty acid metabolism, fatty acid and amino a ...

deficiency ( subacute combined degeneration), compression of the spinal cord in the neck from any cause such as cervical

spondylosis Spondylosis is the degeneration of the vertebral column from any cause. In the more narrow sense, it refers to spinal osteoarthritis, the age-related degeneration of the spinal column, which is the most common cause of spondylosis. The degener ...

disc herniation A disc herniation or spinal disc herniation is an injury to the intervertebral disc between two vertebrae, usually caused by excessive strain or trauma to the spine. It may result in back pain, pain or sensation in different parts of the body, ...

, tumor, and Arnold–Chiari malformation. Lhermitte's sign may also appear during or following high-dose

chemotherapy Chemotherapy (often abbreviated chemo, sometimes CTX and CTx) is the type of cancer treatment that uses one or more anti-cancer drugs (list of chemotherapeutic agents, chemotherapeutic agents or alkylating agents) in a standard chemotherapy re ...

. Irradiation of the

may also evoke it as an early delayed radiation injury, which occurs within 4 months of

radiation therapy Radiation therapy or radiotherapy (RT, RTx, or XRT) is a therapy, treatment using ionizing radiation, generally provided as part of treatment of cancer, cancer therapy to either kill or control the growth of malignancy, malignant cell (biology), ...

. Delayed onset Lhermitte's sign has been reported following head and/or neck trauma. This occurs ~2 1/2 months following injury, without associated neurological symptoms or pain, and typically resolves within 1 year. This sign is also sometimes seen as part of a "

discontinuation syndrome Medication discontinuation is the ceasing of a medication treatment for a patient by either the clinician or the patient themself. When initiated by the clinician, it is known as deprescribing. Medication discontinuation is an important medical pr ...

" associated with certain psychotropic medications, such as selective

serotonin reuptake inhibitors A serotonin reuptake inhibitor (SRI) is a type of drug which acts as a reuptake inhibitor of the neurotransmitter serotonin (5-hydroxytryptamine, or 5-HT) by blocking the action of the serotonin transporter (SERT). This in turn leads to increa ...

and serotonin norepinephrine reuptake inhibitors, particularly

paroxetine Paroxetine ( ), sold under the brand name Paxil among others, is an Antidepressant, antidepressant medication of the selective serotonin reuptake inhibitor (SSRI) class used to treat major depressive disorder, obsessive-compulsive disorder, o ...

and

venlafaxine Venlafaxine, sold under the brand name Effexor among others, is an antidepressant medication of the serotonin–norepinephrine reuptake inhibitor (SNRI) class. It is used to treat major depressive disorder, generalized anxiety disorder, pani ...

. Typically, it only occurs after having taken the medication for some duration, and then stopped or withdrawn rapidly or after administering reduced dose.

Fluoxetine Fluoxetine, sold under the brand name Prozac, among others, is an Antidepressant, antidepressant medication of the selective serotonin reuptake inhibitor (SSRI) class used for the treatment of major depressive disorder, Anxiety disorder, anx ...

, given its very long half-life, can be given as a single small dose, and often avoid Lhermitte's sign and other withdrawal symptoms. In the dental field, three studies (Layzer 1978, Gutmann 1979, Blanco 1983) have identified Lhermitte sign among

nitrous oxide Nitrous oxide (dinitrogen oxide or dinitrogen monoxide), commonly known as laughing gas, nitrous, or factitious air, among others, is a chemical compound, an Nitrogen oxide, oxide of nitrogen with the Chemical formula, formula . At room te ...

abusers. This is likely due to nitrous oxide depletion of vitamin B₁₂ leading to a very severe, rapid deficiency in the absence of supplementation.

Terminology

Lhermitte sign is not attributed to its discoverer. It was first described by

Pierre Marie Pierre Marie (9 September 1853 – 13 April 1940) was a French neurologist and political journalist close to the SFIO. Medical career After finishing medical school, he served as an interne (1878), working as an assistant to neurologist Jean- ...

and Chatelin in 1917.

, a French neurologist and neuropsychiatrist, did not publish his first report until 1920. However, in 1924 he did publish the seminal article on the subject which resulted in it becoming well known.

References

{{DEFAULTSORT:Lhermitte's Sign Symptoms and signs: Nervous system Multiple sclerosis