Handheld Nerve Electrode Insertion Tool

This paper introduces a new type of miniature device to insert an intrafascicular electrode into a peripheral nervous system that is covered with tough tissue membranes. The developed device is called nerve electrode insertion tool (NEIT) and consists of a nerve holder unit and an electrode insertion unit. Users can easily adjust the insertion position and direction of nerve electrodes while freely manipulating this compact handheld device. This paper introduces the form, configuration, and underlying mechanisms of the device and related surgical procedure. Utility tests using elastomer-made nerve models show that the electrode insertion time and position accuracy, respectively, improve from 72.1 to 4.17 s and 0.37 to 0.11 mm when employing the NEIT. Animal experiment results show that multishank planar electrodes (2 × 2 mm
²
) are successfully implanted into sciatic nerves of six rats. Treadmill tests and histological analysis present the neural functions of all the treated nerves are successfully recovered after three weeks. We expect the NEIT to be employed for other kinds of nerve electrodes and simplify the surgical process in neural engineering research.