Placement of reference electrode position in motor nerve conduction study of ulnar nerve while recording from FDI

Background

Ulnar nerve is the second most common entrapment neuropathy in the hand at the wrist and at across elbow. There are various techniques have been developed to diagnosed the entrapment. Ulnar nerve supply to wrist at the two main muscles First Dorsal Interosseous (FDI) and Abductor Digiti Minimi (ADM). Many research shows that FDI muscle is use to diagnose an early entrapment across elbow. Recording from FDI muscles, there is an issue in placing the reference electrode placement due to its positive deflection.

The aim of this research to identify which is the best position to place the reference electrode in FDI muscles.

Method

A total of 46 hands were included in this study.  Data was collected based on the extensive and detailed description mentioned in different research papers. The tests were performed by a qualified clinical physiologist (Neurophysiology) using a Keypoint 9033A07 machine, used in line with departmental protocol (Ulnar nerve screening protocol1.1, 2020). All data was recorded numerically to ensure methodological reliability.

Result

Out of 46 hands tested for the nerve conduction study (NCS) by placing reference electrode in five different places i.e. tendon of the FDI muscles at the base of digit II, over the thumb, tendon of ADM muscles at the base of digit V, At the radial pathway of the wrist and other hand at the FDI tendon. Tendon of the FDI muscles at the base of digit II shows positive deflection in all hands with amplitude rage between 6-15 mV. Over the thumb show the baseline slightly elevated to get accurate distal motor latency with amplitude between 5-8mV. And tendon of ADM muscles at the base of digit V shows correct baseline for accurate distal motor latency with the amplitude rage 10-18mV.

Conclusion

This study shows that to record the best and clear response by placing the reference electrode at the tendon of ADM muscles at the base of digit V is more reliable as compare to other two areas.

What will audience learn from your presentation?

It is crucial to place the reference electrode in proper place with the normative data should be collected.

Dr. Michal Filip works as a neurosurgeon (1984- today) and since 2003 has been teaching and collaborating on scientific research activities at the OSU Faculty of Medicine. In addition to neurosurgical topics (replacement of intervertebral discs and intraoperative tumor US imaging), his long-term research activities include telemedicine applications, virtual reality and BCI. During his many years of career, he participated as lead author or co-author in a large number of studies on these topics published in domestic and international journals. HI 7. The ability to solve the given problem and to successfully lead and coordinate the presented cooperation project is also evidenced by his extensive managerial experience gained in solving national and international projects, as well as long-term cooperation with the commercial and application sphere. He currently collaborates on this research with e.g. the rehabilitation clinic of the OSU Faculty of Medicine, VR Life a.s., Brain Lab a.s., the Department of Applied Informatics and Artificial Intelligence at the Technical University of Zlín, VŠB Ostrava, the Institute of Physics of the University of Silesia, Opava, and is a co-author of research projects on these topics (nationwide the TAČR project and the SMK project). Since 2021, he has been the head of the center of excellence for artificial intelligence, VR and telemedicine at OSU Faculty of Medicine.