Lhermitte's sign

[lârmĭts, lĕr-mēts]
n.
  1. An indication of multiple sclerosis and of disorders of the cervical cord, especially compression, in which sudden electriclike shocks extend down the spine when the head is flexed.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.