Our logo shows a reflex hammer, which is a tool used by physicians to demonstrate muscle stretch reflexes. Depending on the response, this can reflect disorders of the central or peripheral nervous system. The reflex arc shows the how well the bone, muscle, and nerve systems work together. Reflex hammers weren't always used on the human body. The origins of this interesting tool got its start with wine. Wine-makers would tap the sides of their barrels to measure how full they were. Dull sounds meant wine, while resonant sounds meant no wine.
Based on this, in 1761, Austrian physician Leonar Auenbrugger used these same principles on the human chest wall to detect the presence of fluid. By 1826, “percussion hammers” were widely used throughout Europe and carried by physicians. Then, in 1876, Heinrich Erb and Carl Westphal described the patellar tendon reflex (“knee-jerk reflex”) and how it could diagnose neurological disease. To elicit such reflexes, physicians used the percussion hammer, their fingers, or the sides of their hands. In 1888 the first true reflex hammer was revealed by John Madison Taylor.
“In shape it is a cone flattened on the opposite side, with apex and base carefully beveled or rounded, of about the thickness throughout of the human index finger. […] The special feature of this hammer is that the shape of the striking surface is like the outer surface of the extended hand, palm downward, which is most often used in obtaining tendon jerk. The rounded apex end is adopted to reach the biceps tendon at the bend of the arm.”¹
Since then, it has been known as the Taylor or Tomahawk hammer, owing to its resemblance to the single-handed ax tool used by the local indigenous people. There have been multiple variations over the years, but the reflex hammer still remains an important part of your doctor's toolbelt.
¹Taylor JM. New form of percussion hammer. J Nerv Ment Dis 1888;15:253
²Mills CK. Neurology in Philadelphia from 1874 to 1904. J Nerv Ment Die 1904;31:353-367