Lhermitte's sign should cause you to consider that the patient might have ____________

Lhermitte's sign, also called the “barber chair phenomenon," is an electrical-like sensation that runs through the patients back, up to his or her extremities. The sensation may travel back and forth, or up and down along the spine of the patient. To elicit the Lhermitte's sign, the physician allows the patient to flex or bow his or her head. The physician then taps or pounds on the cervical spine of the patient to trigger the Lhermitte's sign. The Lhermitte's sign is a phenomenon that is associated with a variety of conditions, wherein there is a suspected compression or lesion in the upper cervical or lower brainstem, which disrupts the nerve signals as they are traveling throughout the spinal cord. A common condition associated with the Lhermitte's sign, is multiple sclerosis, which is an autoimmune disorder. The myelin sheath of the nerves are damaged or degraded, which causes nerve signal disruption.