Rydel-Seiffer Fork Revisited: Beyond A Simple Case Of Black And White

In 1903, A. Rydel and F.W. Seiffer published the use of what is now commonly known as the Rydel-Seiffer tuning fork.1 In their paper, they described an adaptation of the standard tuning fork to make it semiquantitative on an 8-point scale in measuring vibration sensing. The Rydel-Seiffer tuning fork has been used extensively over the past century and normative values have been published.2 It has also been validated with the use of more modern sensory nerve action potentials.3 Vibration threshold measurement with the Rydel-Seiffer tuning fork is therefore increasingly used in outcome measures assessing neuropathy from diverse etiologies: chemotherapy-induced peripheral neuropathy,4 Charcot-Marie-Tooth disease,5 multifocal motor neuropathy,6 and immune-mediated neuropathies.7