Neurophysiological study for Ulnar Entrapment at Wrist

Abstract

Background:The localization of ulnar nerve entrapment across wrist (UNEAW) may be categorised in a number of ways utilising one of a range of presently available methods via nerve conduction study (NCS). A number of approaches as to how to confirm entrapment at the wrist have been described in the literature. There are number of research paper showing several different ways to confirm entrapment.The aim of this research is to establish, using the best available evidence, a clinically appropriate revision of the current UNEAW nerve conduction study, and to compare this with existing Neurophysiological procedure. The proposed revised research is based on more nuanced, descriptive categories, ranging from ulnar sensory branch in digit V, mid palm ulnar sensory entrapment, sensor-motor entrapment across wrist and involvement of dorsal ulnar cutaneous nerve (DUCN). 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:Of the 46 hands tested, the NCS showed that 21 hands had entrapment only in ulnar sensory branch at digit V, 16 hands showed entrapment below wrist (at the palm), 12 hands showed entrapment across wrist (Guyon’s Canal), 11 hands showed entrapment across elbow involving ulnar sensory branch as well, and only one hand showed sensory entrapment above wrist due to a local injury. Conclusion: The ulnar nerve entrapment at or below wrist could easily be missed. Lack of familiarity of the anatomical localization of ulnar sensory nerve could be misdiagnosed with entrapment across elbow. Nerve conduction study is necessary to diagnose the level of entrapment of ulnar nerve at or below wrist.