Lhermitte’s sign, also called Lhermitte’s phenomenon or barber chair sign, is often one of the first symptoms mentioned by people newly diagnosed with multiple sclerosis (MS). It was first recognized in 1924 by neurologist and neuropsychiatrist Jacques Jean Lhermitte.
Lhermitte’s sign is described as an “electric shock” sensation that passes down the back into the arms and legs when you move or flex the neck. It can be startling and painful, but it’s not life-threatening. The sensation usually lasts only a few seconds but can be intense. With time or with treatment, some people stop experiencing Lhermitte’s sign.
What’s really going on?
Within your body’s central nervous system, the immune system begins to attack the myelin, a fatty substance that normally protects nerve endings. Without myelin, scar tissue forms and begins to block nerve messages, causing a range of symptoms including Lhermitte’s sign.
What should you do?
MS is not the only condition that can cause Lhermitte’s sign. People with other disorders involving the cervical spinal cord, as well as people with severe vitamin B12 deficiencies, can experience it, too. Your doctor will want to rule out all the possibilities to find the best treatment for you.
Treatment and therapy
As with many MS symptoms, if you’re feeling fatigued or overheated, or if you move your head the wrong way (most commonly when your chin hits your chest), you may accidentally trigger Lhermitte's sign.
Your doctor may prescribe the following therapies to help relieve pain:
Electrical stimulating devices, such as TENS (transcutaneous electrical nerve stimulation)