Lhermitte’s sign is sudden electric shock like sensation felt from neck to the spine and further down to the legs and arms. Pronounced as Ler-meets, this sign is elicited by bending the neck forwards mostly in people suffering from multiple sclerosis. However, the sudden electric shock like sensation can also be experienced in other conditions such as vitamin B12 deficiency, transverse myelitis, cervical spondylosis, etc. Lhermitte’s sign is also referred by an alternative name as barber’s chair syndrome.
The movement of neck is similar when the barber tries to cut hair from the back of the head.This sign is one type of nerve pain which is not life threatening but intense even if it is for few seconds or a minute. Lhermitte’s sign is caused when there is miscommunication of messages between the nerve cells caused due to destruction of myelin sheet covering the spinal nerve.
Physiotherapy, neck exercise, TENS and certain drugs are useful in reducing the episodes of neuropathic pain produced in Lhermitte’s sign.
Common Causes Of Lhermitte’s Sign
Lhermitte’s sign occurs when the nerves is not protected by the outer covering layer called myelin. It is one of the most specific sign of multiple sclerosis (MS).Multiple sclerosis is a disease affecting the nerves. In this disease the immune system of the body attacks the myelin sheath, a coating that covers the nerves. When myelin sheath is damaged the nerve cell are exposed and scar tissue can form. This scar tissue can block the signals from nerves that travel to the brain and spinal cord.
Lhermitte’s sign is produced when the damaged nerve of the spinal cord becomes hyper excitable to the movement of neck. The movement produces miscommunication of messages that are sent to brain as the nerve is no longer covered by the sheath. Sometime, the brain may interpret the message as pain, even though there is no cause leading to pain.
Although Lhermitte’s sign is common in multiple sclerosis, there are many other conditions that may have Lhermitte’s sign as one of its symptom. It is also present in cervical spondylosis, disc corrosion, vitamin b12 deficiency, physical trauma, nitric acid toxicity, after chemotherapy, herpes zoster infection, compression of spinal cord etc. The sign is also present in patients taking radiotherapy for head and neck cancer.
Alternative Therapies For Lhermitte’s Sign
Lhermitte’s sign usually occurs when a person bends his neck forwards or sometimes even sideways. The best way is to try and avoid such movement of neck whenever possible if the patient has experienced it in past. Lhermitte’s sign appears suddenly without giving any warning and it lasts for few seconds. So treatment to relieve pain during an episode is not possible as the pain does not last long. However, patient can try to alleviate sharp shooting pain with medication and other supportive therapies.
- Support with soft neck brace is beneficial in reducing the neck movement. Thus reducing the triggering factor which is producing Lhermitte’s sign.
- Physiotherapy exercise to improve posture will help to prevent future attack of pain. The therapist teaches muscle relaxation techniques and deep breathing exercises which are beneficial in reducing paroxysmal symptoms of pain.
- Medications that control seizures are found to be beneficial in pain. Steroids are also used if the patient is known case of multiple sclerosis, which is causing Lhermitte’s sign.
- TENS (transcutaneous electrical nerve stimulation) is also an effective way of treating Lhermitte’s sign.