Tensile Physiology: Measuring Force and Conduction in Peripheral Nerves Undergoing Controlled Stretch

Tensile loading is a common physiological condition for peripheral nerves, but can also induce pathologic effects upon electrophysiological conduction. Functional deficits resulting from nerve elongation are not thoroughly understood. Using a computerized micromanipulator, load cell, and grease gap-recording chamber, a new system for tensile electrophysiology is proposed and demonstrated. This paper examines the effects of tension on conduction through guinea pig sciatic nerves. Nerves were stretched at 0.15 mm/s to 5%, 10%, 15%, and 20% beyond their physiological maximum. Results indicate minimal changes in conduction for 5% elongation. Further strain resulted in approximately linear increases in recorded force and decreases in conduction amplitude.