Tinel's sign

[tĭ-nĕlz, tē-]
n.
  1. A sensation of tingling felt in the distal extremity of a limb when percussion is made over the site of an injured nerve, indicating a partial lesion or early regeneration in the nerve.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.