Lhermitte sign
The Lhermitte's sign (also Lhermitt's phenomenon - after Jean Lhermitte (1877–1959), French neurologist and psychiatrist) is a clinical sign that plays a role in the neurological examination, but also spontaneously by those affected in everyday movements with more or less strong flexion of the neck can be felt.
The sign is checked by the doctor passively moving the patient's head forward (with the chin on the chest). The sign is present when the person being examined feels an uncomfortable to painful, often described as electrifying, feeling in the arms, trunk or legs, which typically radiates from the neck. It is not to be confused with meningism , which is characterized by mostly extremely painful neck stiffness.
The Lhermitte sign comes about through the stretching of the meninges in the spinal column , which are sensitive to pain , in contrast to the nerve tracts of the spinal cord . It is often found in multiple sclerosis , but it can occur in a variety of other diseases that involve foci of inflammation in the spinal cord. Other possible causes are, for example, tumors , advanced arthritis of the vertebrae , myelopathy after radiation and vitamin B12 deficiency .